People shouldn't worry about accuracy too much. Everybody in healthcare knows about the problems in various measurement methods as well as individual responses to measurement anxiety and the physical and emotional state you are in that particular time. The only accurate measurements are direct measurements through an arterial catheter which is a very invasive procedure.
Routine clinic measurements are used only to have a general idea about trend and secondly to catch severely high BP which is usually due to a secondary disease.
Also, if BP is high above a certain limit it is significant regardless of if you took rest for 5 minutes and other precautions. Because if BP is high the normal BP regulating system should kick in and lower it regardless of the cause. With advancing age and hardened arteries this response becomes less optimal and you need the support of anti hypertensive medicines. You can see this in real time in patients under anesthesia. A young healthy patient would have an initial peak in response to pain or other surgical stimulus but they will be able to lower it either spontaneously or with minimal outside intervention. Whereas in older individuals much more effort is required to control and lower the BP.
The general trend has been to treat both hypertension and diabetes early because the microvascular complications start much earlier before they become apparent clinically.
No, “everybody” in healthcare does not know this. I have learned to be skeptical and not to assume any particular level of statistical competence in the healthcare field.
Nurses/healthcare professionals often take the patient's blood pressure and heart rate just as soon as they enter the room after walking and moving about. Wait a few minutes and the measurement changes significantly, giving you a better indication of actual heart rate at rest.
I went in for a checkup and my doctor actually retested me after a few minutes because the first reading was unnaturally high. Hurrying into the office and the general anxiety of being in a hospital certainly raises it by a bit.
I get the sentiment, but let me add one thing. Understanding statistics well is far from "common sense". In general, to operationalize statistics well, one has to both (a) train your mind quite carefully beforehand, and (2) slow down in the moment to make sure your rational thinking modes have traction.
There's definitely a huge variance in blood pressure readings depending on posture, relaxation, arm position, recent activity, etc. If you buy a blood pressure monitor, it's really interesting to see how "random" a single reading at the doctors' is, and how large your fluctuation throughout the day is.
That being said, it really makes me wonder about studies that correlate blood pressure with other things. Is the blood pressure really being measured "correctly" in all those studies? Or not?
In other words, if your "true correct" blood pressure is lower than what the doctor normally takes, but then a lot of the studies are based on real-life "incorrect" higher blood pressures, then don't you similarly want an "incorrect" higher reading for consistency? Or are the studies always really done with far more accurate blood pressure readings, where the patient sits still for 5 min beforehand, keeps their legs uncrossed, is totally free of stress and anxiety, didn't exercise beforehand, etc.?
Another fun factor I learned about five years ago is temperature. My gym was offering a complimentary fitness evaluation, which among other things included a blood pressure test. The trainer was horrified to see 140-something over something equally terrible, and started explaining how she'd have to refer me to a doctor and advise that I refrain from strenuous physical activity, until I showed her a report from my annual physical a few days prior with 106/70. Turns out that walking to the gym in shorts and a T-shirt in late January causes enough vasoconstriction to really screw with some measurements.
I once had a similar high outlier blood pressure reading after a somewhat busy day followed by running through the city to my blood donation appointment. Who knew that BP is affected by external factors and doesn't stay constant throughout the day‽‽
It raises my heartrate as well. I know my bladder is full many times due to the heartrate rather than feeling my bladder. I'm not sure if others notice this. I assumed without looking at the anatomy that the arteries to the lower extremities are under pressure from the bladder.
I had a similar trip to the blood bank once: I rode my motorcycle from Palm Springs to San Diego, straight to the blood bank, on a cold January morning. As usual, they took my temperature. It was 95-something. They said, "Are you feeling alright?" I said, "Sure, I should have worn better clothing for the ride down here, but I'm fine." They conferred, then took my cold blood :-)
No medical advice should be given on the basis of a single blood pressure test.
I've donated blood about a dozen times, my BP has been high on one or two occasions but only if it was a pattern after two or three times did they flag it up, and since it went back down the next time it was no longer a problem.
They did send me letters about the amount of ferritine in the blood though; the first time it was too high (probably due to having a thing for food that turned out to be high in iron for a while around that time) and they advised I see a doctor for it, but it went down on its own after that. And the last time it was too low, but that's a normal thing if you donate blood a few times (it was every two months for a while), they basically don't summon you again for six months.
> Is the blood pressure really being measured "correctly" in all those studies? Or not?
This is why you do readings three different times a day for several days. And why there’s instructions on how long to dust still before the readings, why you do three repeats with multiple minutes of wait in between, and finally why the averages of those readings aren’t just simple averages. But yes you always have to wonder about every study using self reported home readings if they follow the instructions or not, because it is tedious to do it correctly.
The reading process itself is a constant that you can't filter out by doing it repeatedly. Something squeezing your arm with what feels like the force of a hydraulic press surely doesn't have any weird side effects.
Anecdata, but I always get high anxiety from not being sure if the thing is actually still working properly or if it's just gonna keep pumping itself up until it explodes in my face or something. Not exactly rational but these sort of things never are. Looney toons ass machine.
"Something squeezing your arm with what feels like the force of a hydraulic press"
It shouldn't feel that crushing. I know it's common, but it shouldn't be. It's lazy/rushed healthcare professionals who only want to take it one time suing an automated machine and crank it to 200mm. If you actually put it at 140mm or take it with a manual sphig, it would read a "normal" person just fine without the crushing. The problem is, the people who are high around 130-140 need the machine at least 20mm higher and would need a retake, which means more time.
I have an automatic at-home blood pressure device, and it does the same thing. Not 200 mmHg, but high enough that I’d freak out if I didn’t know it was normal and would let up soon enough[1]. Did the product designers do that intentionally while still meeting a spec of “not panicking the user in a way that would elevate blood pressure” and getting approved for sale to non-professionals?
It seems like this is genuinely hard to work around in practice.
[1] I recall it being a staple of 80/90s tv, at least Beavis and Butthead, to have a character use an auto blood pressure device and freak out at being so clamped.
One alternative is a cuff that measures on the upswing, rather than the downswing. It does not tend to squeeze quite as hard, because it stops as soon as it has the systolic reading.
I have omron it has been at least 10 points lower then my other ihealth cuff. I even sent it in, they said was fine. Had the dr check it as well. It was always 10 points lower. I read that omron measures differently than the typical bpm.
To my knowledge Omron is considered one of the gold standards for home BP monitoring. Most of their cuffs measure the same old way, the BP7000 is one of the few models that do an upswing measurement. I've had both, along with periodic measurements at the doctor (I also do not get white coat hypertension). The Omrons have been in agreement with all my "official" measurements.
I have a 6-7 year old Omron brand device that doesn't do this. I can always tell right away when my BP is running high because I can feel the machine squeezing harder than normal to get the reading.
Nah. Modern automatic cuffs are adaptive. They tend to first run up pretty low (like 150), see if there is signal. If not then they have to inflate more and more. They tend to determine where to start next time based on the last reading, so if it had the go up to 200 for the last reading it’ll start there next time. If the cuff is a vise, excluding operator error the most likely cause is actually having high blood pressure.
There is another factor that everyone is ignoring here. Some people are just much more sensitive to that kind of pain. If you Lymphadema, or especially Lipodemia, you are much more likely to experience a lot of pain even when a manual sphygmomanometer is being used.
The Omron BP7000 doesn’t hurt me that much, and I measure mine every morning and every evening. But it does hurt my wife, and she has both conditions.
That anxiety is more present in the first of the readings than the last, so you get an indication if that’s affecting the reading too. You don’t have to be able to filter it out entirely to know if the reading has diagnostic value.
I would trust the self-reported home readings more than those taken by professionals, because they're probably happening more often and under less stressful and exceptional circumstances.
Find one that is accurate enough and crosscheck it with the one at the doctor by taking regular measurements so you get an idea of trends rather than absolute values. Doctors do know about white coat hypertension - it's not a myth. There's no reason you can't do your own experiments with consumer-level blood pressure monitors from reputable manufacturers. In fact, it was my mother's primary care provider who recommended she buy one for home use.
This is what I did with a US$10 pulse oximeter (a Contec CMS50M from China) when my dad ended up in ICU last year, and it was pretty much bang-on with its readings. I've also tested my pulse oximeter on plane trips and know it will drop below 90% when the air is thin (and rise up again if I do some deep breathing), and therefore know it isn't always stuck at a high value.
Search PubMed for "The Accuracy of 6 Inexpensive Pulse Oximeters Not Cleared by the Food and Drug Administration: The Possible Global Public Health Implications".
You might be surprised. "White coat hypertension" is well-known. Someone with a reliable set of readings from home would be more convincing than someone who says "I get it read at Walmart/CVS once a month and it's ok".
Your doctor's office's monitor isn't incredibly accurate. If you want accurate, you need a mercury sphygmomanometer to measure the pressure. Unless fundamental properties of the universe have changed, it will also be comparable to any other readings taken with mercury.
My doctor did. My blood pressure was slightly elevated in his office and I said it happens at every doctor. He said to get a home monitor, test 3 times in the morning, 3 times in the afternoon for a week and bring in the results at the next appt.
Don't worry, your monitor is good enough for the purpose of screening for hypertension. Truth is the exact values don't matter much for this purpose. Only thing that matters is the fact that people die less and develop less complications when treated based on the results. They are still useful even if the figures have some error in them.
It varies of cause, but here the doctor just sends you home with a monitor exactly identical to the one they use at the office. But it’s not like there’s a world of difference to the ones you could buy yourself at a resonable cost.
My wife had a Cryo Chamber Therapy for a few weeks and had to measure pressure and pulse before each session so they let her in. After about a week she was refused entry because her pressure was too high (when she measured it at home - it was normal).
Since then she had problems getting admited every time, and she started to fear the measurement (she had to drive there during work and do overtime later).
She started arguing with the guy and wasted like 5 days driving there and back during work without having another session because the pressure and pulse were too high (despite both being OK at home).
Eventually she went to another person in that hospital to measure her pressure. It was perfect. But when the guy near the entrance to the cryo chamber measured it - it was too high to let her enter.
They tried different instruments and the difference was the same. When the guy measured it - it was too high. When somebody else measured it - it was fine. Finally they let her do the cryo chamber without the guy permission :)
We assumed the difference was just that she was anxious and frustrated when she's seen the guy, but now I wonder if the difference was the position in which he measured the pressure.
Had the exact same thing happen when I was doing a Ketamine therapy thing a while back, and I definitely think the anxiousness about the reading had something to do with it.
I've always had perfectly okay blood pressure whenever I have it done at a regular doctor's appointment, so I think knowing that the reading actually matters definitely increases my blood pressure. Ended up getting a doctor's note saying "they don't actually have high blood pressure they are just reacting normally to possibly having to be sent home and reschedule" more or less.
I get anxious when taking blood pressure as well. There are techniques your wife can try before entering the cryo-chamber look up the 478 breathing technique. I developed a white coat blood pressure readings over the last several years measuring a stage one or stage two hypertension at my last doctor visit. I use the 478 breathing technique and my blood pressure readings are normal at my last dr visit.
When my heart went to hell, I bought a blood pressure monitor. Before I left the hospital, I had to agree to religiously test my blood pressure three times a day at the exact same time. Anything beyond that was a bonus, but to provide useful data I needed those three readings a day.
As my cardiologist explained, 39 year olds don’t randomly end up spending a week in a cardiac ward so he needed better data to form a holistic treatment plan.
I found that that the measured BP was consistently significantly lower if I didn't look at the device's display while it was doing it's thing. This at home, with a quality device, after doing it many many times.
As long as blood pressure variance is randomized then you’re getting a signal, and that happens when everyone is measured in a similar way (or randomized to different ways). You don’t need perfect precision.
What you don’t want is to make everyone who, say, smokes wear the cuff while standing up while everyone else gets cuffed lying down.
> and that happens when everyone is measured in a similar way (or randomized to different ways)
But that's exactly the issue -- that the similarity or randomness is one way for one study, and another way for another study, because of culturally different sets of nurses and/or patients.
In other words, you're right it's not affecting results within a study, but it makes comparison between studies questionable.
And it makes it equally questionable whether a study's results apply to you, if your signal is 10 units off of a study's signal, and occurs across a cutoff that determines whether you should take a medication or not.
> Is the blood pressure really being measured "correctly" in all those studies? Or not?
Probably incorrect in most studies, especially large population ones that influence treatment guidelines.
It’s academic and doesn’t practically matter though.
The pathogenesis of hypertension related disorders (kidney failure, heart failure, stroke etc) is well known.
It’s not in doubt that sustained hypertension is bad, that there is increased risk with higher blood pressure and that patients with high blood pressure undergoing treatment suffer less of these bad outcomes.
Also doctors and nurses are known to do an abject awful job of measuring bp according to the defined procedure. It’s usually way off when taken clinically.
Ars article here but there’s plenty in pubmed too.
> You must not eat, drink, exercise, or smoke within 30 minutes of a reading. You must have an empty bladder. You must sit straight up in a chair with back support. Your legs must be uncrossed and your feet must be flat on the ground. The arm to be measured must be rested on a flat surface so that it is at the same level as your heart, not lower, not higher. You must sit calmly, without talking for five minutes to relax before the reading. When it's time, an appropriately sized cuff should be wrapped around your bare upper arm, right above the elbow; it should never be wrapped over clothing. At least two readings should be taken, with the average recorded. Ideally, readings should be taken in both arms, with the highest readings recorded.
When was the last time you got it measured properly? Literally never for me in a clinical setting. I don’t know why they bother honestly.
What's the point of taking your blood pressure if doing any of these things causes significant variance? I'm not meditating at home or out and about all day. So why does it matter what my blood pressure is in one single state? What if I'm in an elevated state all the time? What if I never am? It makes it really hard to believe that blood pressure readings are anything more than nonsense.
If you're doing a double leg press (especially in conjunction with a Valsalva maneuver) you can get an instant BP reading as high as 320/250. If that's your idle BP then you're not long for this world lol.
If your BP - measured in a specific and consistent set of conditions - is elevated vs baseline then you are at an increased risk for a set of medical conditions. Researchers could have picked any set of conditions to establish that baseline but I assume that idle is easier to standardize on than e.g. double leg press with 3 RIR. It's not which condition per se but rather that it's the condition researchers aligned on and studied.
The problem is that if the risk is established based on your deviation from the baseline, then you must be measured in the same conditions under which the baseline was established otherwise the results don't mean much if anything at all.
The idea, in theory, is to measure your "minimum" or baseline blood pressure.
That your activities throughout the day add variable amounts to the baseline but never go below it.
It is a very good question though -- some people have activities/jobs/lifestyles where their BP is significantly elevated all the time. So surely you would think that must matter?
> Smoking within 30 minutes of measurement can raise the systolic blood pressure to 20 mmHg
> a distended bladder can increase systolic and diastolic measurements by 10 to 15 mmHg.
> Sitting in a chair lacking back support can raise systolic blood pressure to 10 mmHg, and a similar increase is observed when both legs are crossed.
> Talking/listening during measurements can increase systolic and diastolic measurements by 10 mmHg.
The major exception is cuff placement over clothing which is noted to vary results by up to 50 mmHg but doing that is stupid anyway and makes you fail medical school.
For me, the first reading is usually higher (by 20-30, even after a long rest period) and subsequent ones get lower and lower as I calm down from the initial worry about whether I will get a high reading or not.
At the doctor's office / hospital I try to tell them this, but they tend not to care. I think they know it varies a lot, they know about psychological effects, but i) they anyway take it much less seriously than overthinkers like me and some fellow HN-ers would imagine and ii) they may prescribe something and anyway expect it not to do much, and also expect the patient not to follow through with taking it properly etc. Honestly, the whole thing is quite a farce. The painful truth is that generic lifestyle improvements are the biggest bang for your buck, instead of worrying about getting exact and precise blood pressure readings.
The other similar big thing is routine blood tests for deficiencies and cholesterol, iron etc. It can also have huge variance over the year, and often people only do it every one or two years and take it as this extremely solid evidence that you need to take this or that medicine. If we were truly serious about this, we would do several tests, separated by weeks, done with different kit manufacturers at different labs etc.
I think the reason for not doing more thorough testing is implicitly admitting that the results aren't really all that actionable and improved precision doesn't really improve treatments because we have no idea what to really do with the results. There are studies showing correlations/causations of certain interventions on specific markers, and those markers are in turn correlated to some outcomes, but often the "evidence-based medicine" doesn't follow the full chain towards the actual outcome.
The other big reason for not measuring more times is the same that a man with a watch knows the time, but a man with two watches is never quite sure about it. In other words, if you got a test and had a result, you can document this and all is fine.
Good question, for myself personally (anecdotally) I got systolic of 145-ish in the doctor's office and 120-ish at home. This was validated by a medical take-home 24h cuff.
Probably never, I have really long arms and they usually take it just barely above the elbow also. I have always been on the higher end even when in my 20s and training/dieting for athletic events.
Used to flummox me until I bought my own meter, they can be like $30.
Doctors recognize that non-invasive BP measurement is an imperfect screening tool. Anybody worth their salt isn't getting worked up about these level of details, because it's largely a waste of time and effort. The solution to an error prone screening tool is not to repeatedly use the screening tool. You move on to more accurate and focused methods of testing.
> The solution to an error prone screening tool is not to repeatedly use the screening tool.
It can be. Repeated in office blood pressure measurements increase sensitivity and lower specificity. It's not as good as 24 hour monitoring but sometimes that's the best you've got.
> You move on to more accurate and focused methods of testing
Yes, AFTER the imperfect tool gives you something to worry about. So you still need the imperfect tool, which is what I think a lot of people are missing in this conversation.
Kaiser measures BP on every visit and arm position seems like the least of their worries:
- no rest period before measurement
- measured through a medium-thickness sweatshirt sleeve
- cold hospital hallway
- no back on the chair
- no height adjustment on the chair
- no real surface to rest your arm on (They usually use the handle of the equipment cart that the BP monitor is mounted to)
- Zero attention to cuff positioning/orientation
I've come in at 160/90 but went down to 120/80 after rotating the cuff 1-2cm and resting for a few minutes. Manual measurements from the doctor are usually more accurate.
This is why it is better to take three measurements and do an average every time to minimize errors.
The studies on correlation probably have a large enough sample size to become statistically significant - i.e. you have to read the "Method" section to find out how reliable it is, this requires certain kind of statistics and/or scientific background.
Reading around (e.g. [0]) it sounds like variance isn't something researchers care for, probably with the assumption that screening with a higher value is better than missing an issue from a lower value.
We see the same for body temperature (speed and convenience is usually prioritized over accuracy) and weight (2% variation is largely accepted). Afterall guidelines are already off as by definition, as they don't account for individual circumstances, so perhaps aiming for accuracy is useless in most settings.
Kind of wonder the same thing about BMI and water composition. Your body weight can vary by up to 10 pounds depending on how much water you're retaining. I've never been able to find information about the composition assumed or measured when coming up with BMI numbers.
Granted I don't think the ultimate effect is huge, and you can eliminate it by weighing yourself daily and taking an average. But most people don't do that, and a spot-check at a doctor's office certainly can't do that.
> I've never been able to find information about the composition assumed or measured when coming up with BMI numbers.
BMI is just weight divided by height squared. No distinction is made between type of mass. Muscle mass, fat, bone, water? BMI couldn't care less. It sums all that stuff up into a single value.
Think of it as a number that roughly correlates to disease. There will always be false positives and false negatives. False positives are acceptable. We want to minimize the number of false negatives.
There are nearly ten billion humans on Earth. It is not possible to fully evaluate every single one of them. Gotta run a SELECT statement. Filter them based on some criteria, and fully evaluate those that match. BMI isn't perfect, but it takes less than one minute to measure the variables and compute it. The equipment required is cheap and easy to use. Speed, efficiency, cheapness and ease are extremely important factors when you're applying this at national scales.
Patient might turn out to be a physically fit 100 kg 1.7 m 34.6 kg/m2 body builder. That's alright. Our objective is to make sure the obese and the malnourished can't escape the sieve.
I guess it depends on the study. If it is just comparing between groups, the conclusions probably still hold if they consistently measured blood pressure in the "incorrect" way. If it is something like "85% of Americans have high blood pressure", then probably the conclusions are incorrect because they are comparing the "correct" baseline against an incorrect measurement method. There are also other ways to measure blood pressure, like recent smartwatches - so read the methods section carefully, I guess.
> are the studies always really done with far more accurate blood pressure readings, where the patient sits still for 5 min beforehand, keeps their legs uncrossed, is totally free of stress and anxiety, didn't exercise beforehand, etc.?
In situations where blood pressure really matters, we aren't playing around with the cuff and hand positioning. The patient gets an art line.
Oddly, at least a decade ago, at least one Bay Area hospital stroke protocol required manual BP readings with a sphygmomanometer. And the patient had an art line.
Not sure if they didn’t have the equipment for art blood pressure or what, but good BP readings were important. And they had all the fancy equipment. Patient presented with an ischemic stroke, and was getting a stent + thinners, so anything problematic was likely due to something immediately life threatening.
They didn’t want an automatic cuff system because it could cause something to burst with the pressure ramp up. At least that is what the surgeon said.
Source: I was the EMT-B on his clinicals who stayed with the patient in the OR while he got stented and took readings every 5 minutes because none of the nurses were ‘current’ on the manual cuff. or so they said. I was pretty fresh, and was pretty good at it at the time, but I think they were just making excuses now haha. I held his hand through the procedure to help calm him down too, which seemed
to help a lot.
Patient 20 something that day. Emergency Rooms are quite an experience. I volunteered for Halloween Night, which added to it I’m sure.
PS. Watching the Dr install the arterial catheter (or maybe it was a port?) in the ER was wild. Literal stream-of-blood-shooting-across-the-room-and-spraying-on-the-wall wild. Never seen anything like it before or since. I was glad I had my safety glasses on.
Exactly, this is my concern as well. They say you have to be seated for 5 minutes at least, completely relaxed, not hungry, not having to go the bathroom, in a quiet a room, it must not be too hot or too cold, with both your feet on the ground, before you can have your blood pressure measured, otherwise the reading could be 'artificially' high. Really? It seems to me that if you do all these preparations, the reading will be artificially low, since such conditions are nothing like the conditions that you'll typically find yourself in through the day in your everyday life.
The goal is to get a clinically relevant measurement, captured at rest under specific conditions, not a measurement that's representative of a random moment during everyday life.
We're also treating people for things like blood pressure somewhat statistically rather than individually.
The studies say, people who have a blood pressure measured this way, that is above X, have an N% higher chance of dying M years sooner of A, B or C than people who measure under Y. If you treat with medication Q it lowers blood pressure, measured this way, by Z points, increasing lifespan by W QALY.
Are you treating people who don't need to be treated and missing people who do? Could you achieve better results with continuous, invasive blood pressure measurements while the patients engage in every day life?
Probably, but then you're increasing the cost of both the study and the public health intervention exponentially for gains in the margin.
But if the measurement isn't representative of your actual blood pressure what's the point of taking it? It's completely non-informative. Another problem is that even under very controlled conditions, I sometimes find big differences in blood pressure from one minute to the next.
Yes, I was thinking the same. If everyone is measuring heart rate under similar conditions, and then correlating that heart rate with other factors, is that perhaps alright? Can we factor out the "error" to get a working baseline, even if the measurement isn't really heart rate at rest?
I doubt it, frankly. No one is controlling for these conditions. The easiest thing you can do is to wait a few minutes for the patient to relax after entering the examination room to get a reading at rest.
I'm one of them. I bought a device with memory and covered the screen with a piece of card. Then I take BP for two weeks and ignore the first few days' readings. I seem to get used to it after a few days. This gets me readings that are very close to 120/80.
I've had anxiety about blood pressure ever since running for an appointment, while being on the first day of a new job when I was really amped up, and so (of course) had a dangerously high reading. I still remember the guy's eyes widening as he looked at the screen. Ever since then I've hated having BP taken and I can feel my BP and pulse increasing the moment I step into a doctor's office. Fortunately my doctor understands and doesn't try to push pills on me.
I wish there were some way of measuring BP without knowing it's being done. The act of measurement can greatly affect the result, which is counter-productive in several ways (not the least of which is un-needed anxiety).
York Cardiologist on Youtube is good on BP, and why apparently high BP should not automatically mean pills, although undoubtedly it sometimes should. (Usual disclaimer: this is not medical advice, ask your doctor about your specific situation.)
I remember when I was a kid, the doctor thought that my blood pressure was too high. Of course, I was just anxious because I knew they were going to give me a shot. What kid wouldn't be?? He took it again after I got the shot and it went back down to normal.
Try the 4-7-8 Breathing technique while you are traveling to and right before you take the reading. Also just focus on something else like counting things on the wall while they take it. Mine has been high when I take it at the Dr office. But at home fine. I think tried the 4-7-8 Breathing technique this last time and it read normal at the dr office.
Replying to my own comment, but it looks like there's at least one device on the market that measures BP without the wearer knowing it's being done, the Aktiia Optical Blood Pressure Monitor.
Cost about $250-300. It's not available in the US right now officially, though it's cleared in several European countries. I don't know if it's legal to import. If it is, I may well do so.
I take BP readings for someone who gets anxious about them too.
The system we've arrived at is that I play music that relaxes them during the readings. They don't look at the numbers. The first one will be high, so I usually ignore it. I take several readings, look for a couple of consistent ones, then discard any outliers.
Trying to relax always makes me more anxious since it reinforces the idea that there's a danger to be avoided. Over time I've learned the techniques of ERP, which basically does the opposite.
Yeah I'm one of them. I developed a full-on anxiety disorder after my diagnosis with high BP to the point where I would get panic attacks just sitting in front of the device.
At the same time I would became obsessed with measuring BP and pulse...
My current solution besides anti-depressants and therapy is just ignoring it and trust in the pills from the doctor.
Right now I'm thinking about trying something like the Aktiia wearable to get some measurements without me knowing...
I spent several weeks trying to get a dental procedure, where the dentist flat out refused treatment because my BP was high, and every subsequent rescheduling was higher and higher and higher every time. Got a note from my PCP - my dentist still wouldn't do my crown, and was insisting that my PCP do a full screening and review. My dr just gave me some xanax to take before going to the dentist, and never had a problem since. Recently moved, and just straight up asked if I can sign a waiver or something for them to not take my BP at the dentist - new dentist was like "no problem"
I've never looked into research on this subject, but I always assumed this was already well established and known - and it was definitely somewhat already either known or at least believed to be the case:
- Every doctor in the UK I've ever seen do a BP test has made sure the patient's arm is in the right position, rested on a table/cushion if needed, in a way that matches the findings in this study (and while I've only needed my own BP tested once or twice, I've sat in on many, many doctors while they tested the BP of family members of mine).
- My home BP device is a Braun wrist cuff (and is at least a few years old), which has a built in feature that uses an accelerometer to guide you to raise your arm until it's at an angle which means your wrist is at the same level as your heart (this one: https://www.cora.health/guide/best-blood-pressure-monitor/#1... )
I've used the Braun wrist cuff, and while the heart-level feature is cool and perhaps good enough to mitigate position issues, I found that it was very unreliable vs. cuff measurements.
What do I mean by "unreliable"? Two things - (1) internally consistency for the given device and (2) not closely correlated to the arm cuff measurements.
My method: I would wear both devices and take a series of readings (like 5+ from each in a session, and did multiple sessions a day).
My results: while the cuff readings of course had some minor variation in of themselves, they were largely consistent with themselves (i.e. clustered around the average for the session) whereas the properly-positioned (according to the heart height feature) wrist measurements were all over the place showing big swings between readings and a wider dispersion from the mean.
Then there was the issue of did the wrist average measurements roughly correlate to the cuff averages - and not only was the answer "no", it would vary whether it was higher or lower. Which is a shame - it's ok if it was, say, overstating things by +5 mmHg but overstating at that rate consistently (because then you could mentally adjust the outputs); but when it's inconsistent you're just left scratching your head.
As I wrote about in another thread, the continuous wrist monitor Aktiia that I've been trying gets correlated explicitly to an arm cuff and seems far, far more accurate and consistent than this Braun device. It uses optical imaging of your wrist's blood vessels vs. physical pressure on a cuff.
All this to say - test for yourselves! Try multiple arm cuffs, even. While the exact numbers are less important than the trend, you need a device that you can trust w.r.t. output.
It's possible you were unlucky and had a dodgy device (or it's possible luck has misled me to believing mine is better than it is).
I chose it because my GP recommended that in his experience it was accurate, and in addition to testing it against two brands of normal upper-arm cuff (consumer) devices that a friend and a relative had, I also took it when taking my dad to his GP who the previous time had expressed interest in the wrist-based device I'd mentioned using on my dad, and she tested it against her two devices (one an electric upper arm cuff, the other an old-school manual upper arm cuff that involves squeezing a rubber thing on the end of the hose to inflate it and a manual clock-style dial for readings).
We didn't detect any unreliability in it compared to any of those 4 devices (two consumer, two NHS-approved & doctor-owned) - all 5 seemed equally reliable (based on our not exactly lab-quality testing, but still we weren't lazy enough to do single readings or anything like that).
Yes - it's just a digital spirit level of sorts, that instead of being calibrated to align with the ground is calibrated such that, based on typical angles and dimensions of a human body leads to the wearer holding their arm up in front of them with the device in line with the heart.
Here's what it looks like, the device won't start until you've got the ball to hover in the middle circle, but it has no way of knowing if you're doing it properly or if you're lying down or leaning your body forwards or whatever else would mean that the angles no longer put it level with your heart.
Basically the same logic as, for traditional upper arm cuff devices, giving the instruction to rest your arm on something next to you that allows your forearm to be resting both comfortably and straight, parallel to the floor - which again, doesn't technically mean the middle of your upper arm must be level with your heart, but since nobody would really be comfortable putting their forearm flat on a low down coffee table or a high up standing desk it works as a proxy that's simpler than asking people to think about lining anything up with their internal organs.
I am not a doctor and this is not advice. This is a standard medical test I have completely given up on any doctor to perform accurately. I do it myself at home once or twice a month. I do it with the same device, in the same chair, at the same desk, the same time of day, after I’ve ate and drank the same thing. Yes, I still let everyone take it because it’s typically a precondition of receiving care but my readings at home are completely different and give me a more accurate data point that actually makes me feel good about the progress I’ve been making on my health.
I’m actively looking for more healthcare I can do this way. I trust my data and it all coming together on the safety of my personal device. We don’t need doctors with extremely limited datasets to do this and try to find obscure correlations for us.
>This is a standard medical test I have completely given up on any doctor to perform accurately. I do it myself at home once or twice a month. I do it with the same device, in the same chair, at the same desk, the same time of day, after I’ve ate and drank the same thing.
You are assuming the average patient is this careful about measuring their BP, or anything about their health. You are also assuming the average patient measures their BP correctly, which is obviously untrue as evidenced by some other comments on this post. You are also assuming patients always tell the truth about their own measurements.
>We don’t need doctors with extremely limited datasets to do this and try to find obscure correlations for us.
I don't understand what you mean by this. None of us finds obscure correlations with limited datasets. We don't diagnose someone over a single BP measurement.
> We don't diagnose someone over a single BP measurement.
Yeah I feel like no doctor of mine has ever been the type to do that. My current PCP wouldn't prescribe meds for hypertension until after I took my own BP at home for a month (it was not catastrophically high when measured at his office, he might have taken a different approach in that situation).
Even with a catastrophically high measurement, no doctor would diagnose with a single data point. At worst, they would ask the patient to measure at home multiple times a day, after teaching the correct method of measurement. At best, they would do an ambulatory monitoring.
False. I went into a first visit at a doctor office one time and after spending about five minutes total with me he sent me home with a BP Rx. No mention of verifying it with home readings to make sure I really need it and he didn't even bother giving me standard advice like lose weight. Most other doctors did only slightly better. Insurance only reimburses for like 10 minutes of their time, half of which is spent updating records, so it's unsurprising they don't have time to properly handle your problem.
Maybe not a diagnosis, but dependent on history if my patient is throwing repeatable >200 systolic that's probably not one I'm going to just sit on waiting for repeat measurements.
My doctor recommended doing it first thing in the morning, before eating or drinking anything. That's probably an easier way for the general population to establish a consistent baseline
I've achieved exciting results by flatly refusing vitals checks at each and every medical appointment. Especially psychiatrists. The PCPs always gamely admire my self-reported histories and graphs, commenting how nicely the trend line goes down, and then completely dismiss the results in their clinical notes.
However, I did lock horns with a particular chiropractor. I filled out the "pre-existing conditions" form with candor and honesty. I permitted a BP check. (His method was 100% manual sphygmomanometer.)
Then he informed me that he wouldn't touch me until my BP was controlled and normal. Yes, a chiropractor, not a cardiac surgeon. Geez.
In the past, I've tried to avoid submitting to blood draws and labs, because those are 100% fishing expeditions, and not actually attempting to diagnose a complaint or symptoms. (They love to misdiagnose hypothyroid or diabetes so they can begin destroying your endocrines.)
Unfortunately, clinics do these orders on a schedule, so if you avoid labs for a while, the orders simply pile up until they contrive to get them all done. I couldn't win. Still putting off colonoscopy: 2.5 years late, and counting!
Amazing it’s like you’ve figured out the optimal strategy of still spending the same amount of time going to the doctors but getting as few benefits as possible.
I’m pretty sure you can decline care and get second opinions no matter what.
I don’t know your family background, but I have quite a few older male relatives who died from cancers that if caught early have high survivability. They were all suspicious of the profit incentives of the medical system and felt they knew better or were tough enough to not care. My grandfather had a heart murmur, so he used that as an excuse to never go to the doctors. “They just want my money I already know my heart will kill me soon so why bother”. He died of colon cancer. I’m sure they all regretted it.
Every single health related thread is like this. Dude thinks because he's been programming JavaScript for 10 years he's a literal genius. It's pathetic.
No, his quality of life and mental state is severely impacted for years if not decades at a time and he slowly, and very painfully, dies.
My father said the exact same thing about smoking. What's the worst that can happen, I die? Oh no - the worst that can happen is you living far too long.
I intend not to die of chemotherapy. And no, I shall never regret being a prudent steward of taxpayer resources. Let's consider the collective good over an individual's selfish longevity.
What would Mr. Spock say about "The Good of the Many"?
If those involved are in the US, it’s a trust thing.
This isn’t the fault of medical professionals, but rather a system optimized for minimum risk and maximum billing.
For example, my adult son recently went through a bout of rectal bleeding. He sits a lot in his job and we assumed it was hemorrhoids.
It was a Saturday so rather than wait we met up at the local urgent care. They did an external exam and decided he needed to go to the ER. No, it couldn’t wait. We had to go right away.
So we went across the street to the ER and took up a bed for seven hours waiting for a CT scan and results. The CT scan showed no active bleeding or any other cause for concern.
At this point, it was 2AM. The ER doctor suggested we allow our son to be admitted so that they could accelerate a colonoscopy on Monday or Tuesday. Yes, that’s 2-3 days in a hospital room just so we could avoid outpatient delays.
Now, keep in mind, there are no other symptoms. He feels perfectly fine. The CT scan shows no active bleeding.
To us, admission seems like overkill. The doctor isn’t much help. They are mostly exhausted and also exasperated at “the state of health care in this country.” We try to be empathetic but more or less it feels like they are holding back.
So what to do? Well, my son made his own decision - we left. The next day, I called in a favor with a GI doc I know. We were able to get a colonoscopy 10 days later. Guess what? Internal hemorrhoids.
This is irritating enough, but what is even better is that we could have had that answer in 15 minutes if someone had pulled out an anoscope. Sure we’d likely need an colonoscopy as a follow-up but we could have been out of the system very quickly. We could have freed up that bed in the ER. Heck, we didn’t even need to be in the ER at all. Oh, and 10 days of needless worry would be gone.
I asked a hospitalist I know why no one thought to just have a peek. The answer? Oh, they definitely thought about it, but no one uses anoscopes these days. The preferred route is a colonoscopy. Why? Well, a colonoscopy is a better diagnostic tool, but frankly it also happens to allow for better billing.
And boy, oh boy is the billing good. For the hospital alone, we’ve got upwards of $6K in billing. Who knows what the colonoscopy will run. We have good insurance but to cover the deductible I’ll likely be out $2K.
Naturally, I’ve already called the hospital and asked them to conduct a billing review, which will be followed by a medical review. The result will likely be a claim by the hospital that all procedures were followed correctly, which is technically correct. They did it all by the book, wasted an enormous amount of time and money, and irritated all humans involved.
Anyway, this anecdotal story might explain why well-educated people are suspicious of modern medical practices (at least in the US).
FWIW, I’m in my mid-50s and I’ve not had a colonoscopy either, and I won’t be getting one. It isn’t that I don’t want to take care of myself but rather I can’t afford to actually know if I’m sick. In the end, squeezing a little extra life out isn’t worth the financial tradeoff for my family in the long run.
But why go to these practitioners if you don't trust them ? Nobody should be forcing you. Is it because you want access to treatment solely on your own terms ?
Nobody is "forced" to get health care in the United States, [except once you're unconscious, insane, or incarcerated, and the ambulance arrives] but what are the penalties if we don't? A PCP is the only one who can route me to a specialist if I really needed one. If I broke my leg again, or had some other emergency, it'd be nice to have a followup with someone who already has us on file, rather than trying to get past all the gatekeepers for an initial visit.
Every insurance company will urge their customers to establish and visit the PCP on the regular. Every social services agency simply assumes... demands... that citizens have a relationship with medicine and that we dutifully visit the doctor to keep up on health issues. It's outright heresy and treason to say that you won't participate at all.
A physician is the only one who can keep records relating to disability cases. A physician is the only one who can write me a note if I'm unable to work. Eventually you'll need to release medical records to a third party in order to access benefits or qualify for something, so those records had better pre-exist! A physician is the only one who can diagnose or treat any disease, so what else would we do if we got truly sick?
I understand what you say, and there is some truth to it. However it's also justified that society asks something in return for societal benefits. That's pretty much the foundings of insurance. The extent to which that should go is debatable, of course.
> They love to misdiagnose hypothyroid or diabetes so they can begin destroying your endocrines
Im sorry but as a doctor this made me crack up. I don't know what it is about HN that makes people jump into every medical thread and say really absurd things. Skipping screening tests isn't one-upping your PCP. You just get to play harder with specialty when stuff starts to break. Good luck buddy.
It's not just medical threads, it's tech too. You (probably, I'm assuming) just don't know the tech as well as you do the medicine, so it doesn't stand out as absurd to you.
I have expertise in both. I think the difference is that when moving from the highly rigid world of medicine into tech, I expected the varied level of skill and knowledge that exists. It just throws you off seeing people in tech with no background in medicine talk about medicine like they know it.
Most of my closest friends are docs. A couple of times at a brewery I've had them read some braindead takes from here for laughs. The people here making wild comments on the architecture of o1 or whatever don't get the same reaction from the crowd.
I see people speaking complete falsehoods about things I have material knowledge of here, and either don't have the energy or the latitude to correct them.
And those reactions to (e.g.) o1 speculation are happening in (e.g.) OpenAI, I'm sure, haha.
Blood pressure measurements at the doctor are the bane of my (medical) existence. Mix minor white coat syndrome with time blindness and you suddenly have high blood pressure because you barreled up the stairs to the second floor office moments before the nurse took a reading.
My doctor was initially befuddled because by all other metrics I am in good health, but it’s amazing how you can go from 90/55 at home to 140/75 at the office. We do the measurement at the end of the appointment now to varying success.
Literally the first year of medical school, we were taught to let the patient rest for at least 5 minutes before taking vitals, while also asking about recent exercises or caffeine intake. This reduces the likelihood of a mistake, but white coat hypertension is still a thing. That's why we also teach them/relatives how to correctly measure BP on their own and ask them to measure it at home, preferably after waking up before eating anything.
My wife has one specific guy doing the measurement that she hates and when he measures her pressure it's like 10-20 higher.
It's also the guy that measures pressure before letting people enter to the cryo chamber, so she spend about a week rescheduling and arguing with him to let her in.
When she went to another person at the hospital her pressure was perfectly fine, and switching the instruments didn't helped - if THE guy measured it - it was too high - when it was somebody else - it was OK, no matter the instrument used :)
Definitely possible. Blood pressure fluctuates during the day. Activation of the sympathetic nervous system causes the BP to increase. So technically the measurements were "correct", but it was misleading because when talking about BP we normally mean "resting BP".
No doctor or assistant bothered to tell me about the impact of caffeine. I had a few borderline-high readings over a few months and was concerned until I realized I was drinking my normal 2-3 cups of highly caffeinated coffee just before these visits.
Weird, I ride my bike to the doctor, my heart rate is often elevated from the ride and my blood pressure is still normal (barely above low - though I've had enough different tests over the years to believe that exercise is having nearly zero effect)
Lie down on a bed on your back, and put the cuff on your arm and get the 'button' within reach of your finger to turn it on. Then completely relax (and DO NOT move) with soft music or whatever. Then without moving your body at all, after 10 minutes (at least) push the button to start the pressurization and reading.
This gives an accurate reading and is often DRAMATICALLY lower than if you don't do it this way. I was convinced I had super high potentially life-threatening BP until I learned this.
Now if you want to see I'm right, get up and walk around some and then sit back down and take another reading. It will be noticeably higher, because your heart starts pumping harder even from minimal movement.
>This gives an accurate reading and is often DRAMATICALLY lower
Just because it gives lower results doesn't mean it's more accurate. I can raise my arm during measurement or use a tourniquet above the cuff and get a lower result. That doesn't mean the measurement is accurate at all.
There are standardized procedures on how to measure BP. Your "accurate" method is not one of them.
The word "accurate" was the wrong choice of words. The machine itself is always going to be "accurate" if it's working correctly, and cuff is used right. Perhaps "proper" was a better word, since we're not talking about the accuracy of a measurement.
Since you'll get a higher readout after exercise, or even moderate daily activities, it's recommended that the person be perfectly relaxed for a few minutes before taking the reading. What I described is just my way of being perfectly relaxed, and what I know for a fact doctors do if they suspect an actual BP problem, and want to "scrutinize" it to find the true lowest resting reading.
I don't disagree, but wouldn't the counterargument be that the 120/80 and 140/90 thresholds (or whatever they've redefined hypertension as) apply precisely to sitting rather than lying, and after only a minute's stillness, rather than ten? And also that you spend 16 hours out of 24 not lying down?
You don’t live your day to day life listening to soft music, lying down ready to doze. If your BP is elevated due to stress throughout the day it’s elevated, you will accumulate the harms. Idealizing conditions also gives a misleading reading.
> Now if you want to see I'm right, get up and walk around some and then sit back down and take another reading.
This doesn’t prove you’re right, just demonstrates normal physiology. Kind of like saying when you dyno an engine you should do it at idle. That is a valid measurement, just not the one that’s interesting.
In a healthy adult you will see a more significant increase in systolic pressure, but mean pressure shouldn’t rise nearly as greatly.
What you’re trying to observe is not the minimum ideal (your method) nor the short term maximums but an average of normal activity.
There’s a reason why ambulatory BP monitoring is the gold standard for diagnosing hypertension.
If you go to an emergency room and say you've taken your BP and it's high, they'll do basically what I said. Lay you down, let you relax 10 min, and then take a reading. If the reading comes up 120/80 they'll say go home, you're fine, whatever you did to take the BP yourself was wrong. I've seen this happen to someone. That's how I know.
You are confusing the assessment of an acute condition with a chronic one.
There is a huge difference between assessing and treating an acute elevated BP and chronic hypertension. ERs don’t treat or admit to the hospital for chronic hypertension.
As I said, you can’t assess chronic hypertension by only evaluating in idealized circumstances, however this is a fine enough way for ruling out hypertensive emergency which is all an ER cares to do. And yes, you want to idealize conditions if you’re considering aggressive emergent treatment protocols that can have serious side effects.
Like I said, the best option for evaluating chronic hypertension is 24 hour ambulatory BP (which of course would include quite a bit of resting time) - usually 15 to 30 minute intervals. Why? I think the first two sentences of the prior comment are pretty intuitive.
And truth be told if the reading comes up 160/100 they’ll still send you home and tell you to follow-up with your PCP. There are of course other factors (like say having heart failure, symptoms other than headache), but usually it’s BP north of 180/120 where the ER starts getting concerned, and even then you will likely be released for outpatient follow-up +/- some oral medication.
In the public, hypertension is primarily a chronic condition and a slow killer. There are only a few circumstances where rapid control of blood pressure is not counterproductive since over time your body compensates while your organs (primarily kidneys, heart, and brain/eyes) slowly worsen in function.
No I'm not confusing anything with anything else. You've just gotten offended over something -- probably the word "wrong" in my original post, which made you then decide to take it over literally.
I think people will get 90% of the way to lowest BP reading simply by being still and silent for 10 mins. I doubt the lying down part is that important. I just originally didn't know that. I'd be doing something active (or just worked out), then decide to take BP and get a high reading. I think you probably assumed every word of my initial post was meant to be an absolute thing, rather than a general idea of the necessity to be relaxed not only during the reading but for several minutes before.
Yeah, I'm not even reading your latest list of grievances and pedantic nit-picking. If you don't think people should be relaxed when taking a BP reading, I only have two words for you "Google it."
You managed to spout enough crap about the history of Javascript that it summoned Brendan Eich himself, and you even then continued to double down. It really seems like you might get some benefit by taking a deep breath and not letting every correction or even just piece of added information enrage you. That may also likely help your blood pressure.
No grievance. We've never interacted before (nice edit, btw). Yes, the outsized defensiveness did prompt to see what I was dealing with.
After rereading my initial reply I am still puzzled as to why pointing out that ambulatory measurements matter got you bent out of shape. I can concede that "Idealizing conditions also gives a misleading reading." could probably be better worded as "gives a misleading picture", but I don't think that warranted such defensiveness and hostility, you seem to have ignored the overall point made in that comment.
I've heard that for some people it's exactly the opposite. Standard procedure, IIRC, is to have the arm resting in a position that puts the cuff right about even with your heart. But some people get really big jumps in BP when supine, and I've heard it suggested that doctors might want to start doing their BP tests in that position because those people may not get diagnosed correctly despite spending a third of every day with high blood pressure.
I think the main point is not necessarily the laying down part, but it's just that you need to be perfectly still for 10 min. Your BP will still be dropping more even after 5 min. This is just how to get the lowest resting reading. Of course others on this thread have balked about whether this lowest readout has value on it's own.
Measuring at a single point in time is so inaccurate due to things as simple as circadian variation of blood pressure (morning surge, night time dipping, etc). Not to mention acute stressors, arm positions etc. It's hard to put any weight on a single reading, and tbh doctors already know this.
After some hypertension issues last year I bought an inexpensive ambulatory monitor (Contec ABPM50) for experimenting. Turns out the biggest contributor was likely undiagnosed sleep apnea, infact research suggests up-to 50% of essential hypertension cases are probably apnea related [1].
Sleep apnea is ridiculously common and significant apnea in young/middle aged individuals (particularly women) is associated with an up-to 5x increase in all causes mortality [2].
If have poor sleep, mental health issues
(PTSD/anxiety/depression) and borderline/hypertension you should absolutely order something like a WatchPAT test. The odds of it coming back positive are probably 80%+. The STOP-BANG questionnaire is also pretty good: https://www.mdcalc.com/calc/3992/stop-bang-score-obstructive...
1. Chaudhary SC, Gupta P, Sawlani KK, Gupta KK, Singh A, Usman K, et al. Obstructive sleep apnea in hypertension. Cureus [Internet]. 2023 Apr 27; Available from: https://doi.org/10.7759/cureus.38229
2. Lavie P, Lavie L, Herer P. All-cause mortality in males with sleep apnoea syndrome: declining mortality rates with age. European Respiratory Journal [Internet]. 2005 Feb 28;25(3):514–20. Available from: https://doi.org/10.1183/09031936.05.00051504
Maybe someone could take the time to explain how it actually works. Somehow I missed it in my engineering education.
You have a bladder that goes around someone's arm, and it is inflated. It slowly deflates, and somehow this tells you the pressure in the blood vessels inside the arm.
But that raises some questions:
1) Your arm isn't just blood vessel, most of it is bone and muscle. And fat.
2) How does the inflation help? What about the deflation?
The cuff inflates to constrict the brachial artery until it is completely closed (i.e. the cuff detects no pulse, i.e. the external pressure from the cuff exceeds the maximum systolic blood pressure). Then it deflates until it detects a pulse as blood once again is able to force through the cuff's constriction (this threshold tells it the systolic blood pressure). It continues deflating until once again it detects no pulse (i.e. the minimum diastolic blood pressure exceeds the pressure exerted by the cuff).
I am a skeptic about the diagnostic criteria for hypertension, and especially about low targets for management. Cochrane did a meta review not long ago that made it sound like the signal was pretty weak below about 160/100 (as you might expect, if the measurement wasn't very accurate, which I don't think it is). I'm not saying it's not dangerous at much higher levels, but if you're freaking out at 140/90 because a chart says STAGE TWO, imo you can take a chill pill.
Not surprised to hear about Cochrane's results. The science does smell funny. I read a bunch of hypertension papers this last year (I have a home machine and wanted to know how to interpret the results). Beyond the fact that inter-reading repeatability is very poor and a lot of the explanations are very ad-hoc ("fear of doctors" etc), there are other issues.
First problem: natural variance across healthy people is huge. Doctors have a target they think everyone should hit but it's just a gross average, they don't seem to take into account the possibility of genetic variance at all.
Second related problem: it's common to be told what a healthy BP is for an "adult" although BP averages for men and women are quite different, and BP is also heavily affected by age (controlling for health).
Third problem: correlation is not causation. It's a cliché because it's a real issue. The public health community is prone to blurring the line between "two variables are found to be related in a study" and "one therefore causes the other" without doing the work to prove causality, and when I went looking for what studies established BP->cardiovascular disease causality it was remarkably hard to locate firm evidence. It could easily be the other way around. Indeed in most hydraulic systems it's understood that pressure is the result of other mechanisms and under/over pressure is the result of malfunction in pumps or piping. In healthcare they argue it's the reverse: that over/under pressure is the cause of malfunction elsewhere. There's probably a circular relationship but all the material targeted at regular people makes strong claims of causality when the underlying literature seems far less certain.
Fourth problem: perhaps unsurprisingly given the third problem I found studies where people were put on anti-hypertensives and there was no improvement. Actually I read one study where the treatment outcome was purely negative: there was no effect on heart disease or other outcomes of interest but there were lots of patients who fainted due to excessively low BP. This study seemed reasonable well constructed but the negative outcome didn't seem to reduce the field's certainty in anything (a super common problem in public health). Doing trials like this is hard because any time anti-hypertension drugs fail to work it's interpreted as evidence that the damage was already done earlier in life thus requiring ever longer studies to detect.
Fifth problem: a lot of the underlying scientific claims trace back to one longitudinal study in a single village in Japan, done decades ago. It's remarkable how often you follow citations and end up back at this dataset. When you look at what the study did it's kinda sketchy and not particularly convincing, but because the BP->CVD link is hypothesized to be a very slow acting effect it takes a huge effort to collect data. The field seems to be caught in a loop where they exaggerated their confidence early, so now there is not seen to be much point in doing better studies because it'd take years (bad for your career) and why study something that's already "known".
I’ve never seen a discussion how ‘reactive’ one is physiologically either when discussing BP. That is, is one the kind of person who is generally calm throughout the day, or is one who has larger swings based on various stimuli? I’ve had readings as high as 155/95 when stressed rushing to a doctor’s office visit and readings as low as 105/62 when calmer. I suspect blood pressures varies wildly through the day, and this variation depends on a person’s physiology.
>I’ve never seen a discussion how ‘reactive’ one is physiologically
Then you have never looked for it. This is pretty basic stuff taught in the very first year of the medical school.
>when stressed rushing to a doctor’s office visit
Even has a name: white coat hypertension.
>I suspect blood pressures varies wildly through the day, and this variation depends on a person’s physiology.
Yes it absolutely does. Just like your heart rate varies throughout the day, your BP keeps changing as well. That's why we like to measure it over 24 hours before any diagnosis.
Well then, instead of being smug, how about providing a reference? Specifically, can you link to information about the distribution of individual blood pressure daily variances across a population? This is different from white coat hypertension,something which nearly all of us are familiar.
To get you going here is a 2009 article on labile hypertension. It discuss the topic but does not provide any quantitative information on population distribution.
Apparently, contrary to your assertion that an individual’s blood pressure variability is part of established 1st years med student’s knowledge, labile hypertension seems to be an active area of research.
I had a major heart scare when I was 39 so I’m quite obsessed with my blood pressure. This is anecdata based off of my own experience with my heart, brain and body.
(Note that this is based off of someone capable of developing a heart problem in his late thirties so hopefully none of this will apply.)
Before I started running for fun, running up to a doctor’s office would absolutely spike my blood pressure. That was a combination of anxiety (which is/was an issue), cardiovascular health and basic physical reactions to exertion. Since I started running for fun, that relationship has completely changed. I don’t get the anxiety based blood pressure changes because I find running really fun and rewarding.
When I lift weights, my blood pressure will read a little higher for at least 24 hours after. The heavier I lift, the more my blood pressure will lift. I see a similar relationship with volume, but it’s not as linear as weight. So if I have to do fifty total reps to failure my blood pressure will be higher, but not as high as if I had done ten total reps to failure.
Food and alcohol have tremendous impacts. Cannabis has an impact but nowhere near the impact of either food or alcohol. Armed only with blood pressure data, I could make a good case for fast food and beer to be illegal. My case wouldn’t be as strong for cannabis. Caffeine is really fucking weird - it increases blood pressure up to the point of addiction. Then, not feeding the addiction will spike my blood pressure even more.
And I haven’t even begun to talk about how heavily my brain is involved. I dealt with undiagnosed ADHD through developing some very obsessive habits. As a consequence, I can quite literally obsess my way back to blood pressure medication.
Judging by how much personal data I have on my blood pressure, I’m sure you’re very surprised that I tend to be obsessive. :)
So anecdotally, you are 100% correct. But I can add some more anecdotes to hopefully ease your mind. When I got out of the hospital, I had to promise my cardiologist three perfect readings a day; meaning that I would religiously check my blood pressure at the same three times each day. Needless to say, I checked it way more than that. But there is an awareness that different levels of need require different levels of scrutiny.
The only part I still wonder is if my cardiologist knew that giving an obsessive person metrics would lead me into running. This may have just been a way to get me back into shape.
One of my attendings has a running joke where he takes fresh interns in July and tells them "I will take you to <most expensive restaurant in my city> if you can take this patient's blood pressure correctly." He's been doing this for 30 years and no one has been treated to dinner yet. He's looking for the standard rest time, arm at heart level, everything.
After reading both the article and your comment I have to say I'm somewhat confused. I don't think I've ever had a medical professional not take all the right steps when taking a reading, is it common in some context?
I've never seen a nurse not insist on the right position.
However I've always wondered how much of a difference my long torso makes when my blood pressure is measured. I'm 6'3", and it's mostly torso. The result is that a table that is the right height for most people, is low for me. And adjusting the table to match my body is something that I've seen a lot of variation on.
Seems it would be easy to equip exam rooms with a set of basic foam blocks that could help with patient positioning for this and other routine procedures.
Can any medical professionals chime in on how it's usually done for tall folks?
"Long torso body type" is, in general, an under-appreciated factor in ergonomics and product design, IMO.
A couple of off-the-cuff examples:
-The longer your torso, the worse a laptop computer affects your neck and posture. For long folks, upright posture requires keyboard and monitor to be vertically separated even more than most off-the-shelf monitor/desk/keyboard trays will allow. So a monitor hinged directly to a keyboard is the worst of all possible configurations.
-Most recent automotive seats seem to force the head forward, excessively curving the spine, and the longer the torso the worse the effect.
On the opposite side of the bell curve, a safe driving position is hard to achieve for drivers around 5ft tall and under. Correct/safe distance from airbags and pedals seems to be overlooked for those of shorter stature.
I wish solving problems experienced by body proportion outliers was a higher priority for product companies.
That isn't just recent automotive seats. I've been having that problem for decades. Particularly bad offenders are Budget rental trucks and airline seats.
But it is getting worse. The more ergonomic they try to make the seat, the worse it is to sit in. My usual reaction to renting a car is, "Well, there's another model that I'd never consider buying."
Add clothes to that list. It's such a pain in the butt to find shirts made for people who are long torso without ending up with a shirt that's larger in every other dimension too. Even ones specifically labeled 'tall'
You need to find brands that have a slim sizing variation, coupled with a tall sizing variation. Ex j crew pre private equity, had good slim tall offerings.
Why are recent auto head rests doing this? I hate it and I am nearly to the point of removing the head rest when I drive (but maybe that has downsides in an accident scenario).
> "If you are consistently measuring blood pressure with an unsupported arm, and that gives you an overestimated BP of 6.5 mmHg, that's a potential difference between a systolic BP of 123 and 130, or 133 and 140—which is considered stage 2 hypertension,"
Okay, but that's a small and borderline difference?
If you're +-7 in your reading, don't panic yet. If you're there with a stage 1 or 2 hypertension diagnosis (130-140+ systolic), the margin of error discussed in this article isn't necessarily meaningless, but remarkably close to it - you need to address an issue there.
More as a PSA for you hardworking programmers and IT managers out there: if you have chronic hypertension, address it sooner than later. If you think to yourself that you'll start jogging daily starting next week, and your doctor is giving you the option for meds, just get on the damn meds. If you start an exercise regimen that can quantifiably manage it without the meds later, great. Don't let the perfect be the enemy of the good. Hypertension is the silent killer, and before it kills it contributes to all sorts of other bad problems and conditions.
Yeah, I empathize. Glad you're doing better now, assuming you are. I would get awful headaches and nausea (like hide in a dark room, photophobic, overly sensitive to sound, smells, wishing I could chop my head off). For years I didn't connect the two. Felt like getting the worst two-day hangover without having drank anything, but if I had measured my blood pressure at the time it would have been well over 150. I clocked in at 170 during one of those episodes when I went to urgent care. For years I had just dismissed as having overdid it the prior week and just needed to rest. Even if you can put up with the pain like a badass, it's not healthy for your system to be redlining so often. It does its damage in the aggregate.
As a just-in-time bordering on chronically late individual (typical engineer), sprinting on foot or bicycle to the doctor’s office has led to some unusually high reading.
I had a similar issue, which was remedied by getting a larger cuff. In retrospect it makes sense that one size does not fit all, and apparently my biceps are on the larger side.
Cuff sizes are targeted to a range of arm sizes. The range should be stated either on the cuff or in the manual. Using improper sizes over/underestimates the pressure values.
Yes, and that's so obvious in hindsight, but the monitor I was given at the doctor's office came with a size that was too small for me. It's not something one thinks about until it becomes an issues.
I was also fed up with inaccurate readings, and was trying to prototype a medical device that would have an adjustable cuff based on arm size. I ran it by my concierge doc, but apparently the latest tech is to use light waves to measure BP, similar to how wearables are doing pulse OX and Heart Rate. The technique is known as Photoplethysmography (PPG).
Putting aside the implementation technicalities, which I know nothing about, I'm convinced that markedly superior outcomes will be driven by something (e.g. watch-like devices) that captures entire weeks worth of regular BP readings across all times of day and night to provide a significant body of data.
I always figure it’s just a good method to track changes in trends - not so much is this reading accurate, but how does it compare to the last 20 you’ve taken - has your blood pressure been trending upwards? Might want to get that looked at.
Only time I ever recall a nurse that insisted on doing BP measurements wrong was .. in jail. And not like all the nurses there, just this one person who did not care about anything besides flirting with corrections officers and getting the hell out of there ASAP.
Found out I had been worried about my blood pressure for no reason for close to 4 years. When I moved I brought it up to my new doctor and he said "what color was the cuff". Turns out they were using one entirely too small for my arm, which wouldn't you know it gives false-high readings. Turns out my blood pressure is frickin perfect.
The study tested two incorrect positions and the correct position. It “confirmed” that the correct position is correct.
So it’s nothing new, and not anything that isn’t in practice and part of basic procedure
> And they underscore the importance of adhering to clinical guidelines calling for firm support on a desk or other surface when measuring blood pressure, the investigators add.
Aside from this, a lot of medical professionals, particularly the PA’s, seem to be very low knowledge on how to identify the veracity of blood pressure readings. I’ve multiple times had to ask them to retake the blood pressure when the reading was very high or low. It was really surprising the first time it happened and made me wonder what else is getting misreported
every time I get my blood pressure measured, my arm hangs on some scaffolding thing the blood pressure cuff hangs from. not even an armrest. Height is also not really standard.
that said, arm was not in my lap, and not hanging freely at my side.
If it’s happening systematically to almost everyone than the whole system has been calibrated to that. Probably want measurements to be slightly high to err on the side of caution anyways.
I have long arms which I think makes the difference more pronounced. I see a much larger difference than most people if my arm isn't supported at heart level.
In my experience in the US, nurses at primary care practices don’t really care and have no passion for their profession and the younger doctors are Anki flashcard veterans who could be replaced with a LLM and probably have the same outcome. Even DOs act like MDs these days- I guess it is easier to just write a prescription than advise traditional diets.
120/80 is an ideal blood pressure based on studies that show an association between elevated readings and an increased risk of heart attacks and strokes. More than half of humanity has a higher blood pressure than that. I believe most would have much lower readings if they stopped eating the trash food that capitalism has produced.
I jog, cycle, other light sports, work is walking a fair bit, and i eat well - zero trash, and even with meds I'm still way above 120/80.
Heredity seems to play a part (my guess).
Wearing a waffle pattern shirt can also make the reading high. My blood pressure is 20 points higher if I wear a waffle pattern shirt than if I take it off.
That sounds like the guy who thought he had a leather allergy because whenever he woke up with his shoes still on he had a terrible headache and felt nauseous.
It only happens with waffle pattern shirts and changing shirts causes a consistent decrease in blood pressure measurements. My doctor pointed it out when I got a physical because he'd seen the same thing before with other people.
Real-life medical practice is basically going through the motions, then intuitively guessing the issue, prescribing something common since most cases are so banal and next patient please.
Engineer-minded people can discover lots and lots of such "obvious" issues in healthcare and of course the answer isn't that nobody would've guessed it, it just doesn't matter. Healthcare (outside of very specific diagnosable illnesses) is 90%+ medicine theater. People expect some pills, they want a few words with someone in a white coat, and their problem goes away usually by itself. Chronic persistent issues without obvious cause befuddle docs and they often don't find anything even after lots of tests.
Our better health and longevity today is more due to better work conditions, better food, better sanitation and food preservation, basic vaccines, basic disinfectants, basics like penicillin, smoking less etc. And the low hanging fruit to improve further is lifestyle: eating/drinking fewer calories (especially less sugary stuff), exercising/sleeping more and having better social connections. None of it is particularly arcane or in need of precise measurement.
> Engineer-minded people can discover lots and lots of such "obvious" issues in healthcare
It is a defining characteristic of "engineer-minded people" to think they understand better than others. Amusingly, they won't pretend to repair their car engine better than a mechanic, but they will strongly believe they understand all the bad tricks and failings of doctors. They almost never understand that current medicine is mostly experience and not hard science. Future medicine is science. 2024 medicine is not, and cannot be.
I wouldn't put the blame on them though. There's a lot of obfuscation and posing as science.
But at the moment it's intractable to do it at scale at a meticulous, evidence-based way. It's a bit of a Santa Claus moment to realize this. People want to believe someone has a proper grip on things. Medicine has done wonders in narrow, specific things like various surgeries - I'm mostly talking about everyday GP stuff where some average 65 year old has generic issues like blood pressure. It doesn't mean that nothing can be done, and I'll in fact say that a smart person with some biology/chemistry background and internet access can often figure out what they actually need,better than a median doctor with limited time and little deep thought effort to spend on the case.
Cultural change is very hard, especially since doctors enjoy a very high status which they earned through long years of very hard work. So the attitude similar to the opposition to Semmelweis persists.
Honestly I'm not sure what a single point-in-time reading even accomplishes. I've been hooked up to a continuous blood pressure monitor a few times and it's always fun to see how low I can get it. It seems pretty useless without seeing where it fluctuates over time not in a doctor's office.
Aktiia makes a continuous optical blood pressure monitor that is available in the EU. It's like wearing a fitbit, but for bp. You calibrate it with a pressure cuff once a month.
I'm pretty sure they're going through fda approval in the USA now.
Once, when hospitalized, I had an arterial BP monitor that was continuous. The last systolic number I remember seeing before passing out from sepsis was in the 70s.
Just settle on a standard arm position for the measurement and set the standards for that position.
I mean, you could even set the standard to be measured at the neck while the patient is hanging upside down and still the average would be average and the outliers would be outliers.
Yet another medical topic being discussed on HN, with comments full of disinformation and skeptics that think they've noticed something new that doctors have missed. Remember people, don't take medical advice from HN.
Well, it's clearly an echo chamber. There's very little actual transmission of knowledge in those topics. It's almost always about confirming pre existing beliefs.
I'm an MD too, but I've been raised by scientists. Scientists in my own family entertain the same beliefs exhibited by HNers, to surprising extremes such as dismissing the effect of even very well understood drugs.
Last year, my father stopped his blood pressure meds and was very surprised when I could guess he'd stopped just by looking at him, then proceeded to explain how the drugs acted, and got even more surprised when he got much better 15 min after taking them again. Since then, he totally forgot about this event and is in complete denial.
You can't change beliefs by explanation. People have to get to their own conclusions, otherwise you're just fighting windmills all the time.
Nice to see a fellow MD (very possibly older and more experienced than me) on HN.
>he totally forgot about this event and is in complete denial.
I can never understand this, especially with well educated people like your father or mine. I can't get mine to agree to go see a doctor (other than me - he doesn't believe me when I tell him something about medicine) for anything, even when there are obvious problems with his health.
TLDR: Rest arm on table while taking a reading. Don't let your arm hang, unsupported, or flop on your lap. (15th paragraph has the meat of the article).
People shouldn't worry about accuracy too much. Everybody in healthcare knows about the problems in various measurement methods as well as individual responses to measurement anxiety and the physical and emotional state you are in that particular time. The only accurate measurements are direct measurements through an arterial catheter which is a very invasive procedure. Routine clinic measurements are used only to have a general idea about trend and secondly to catch severely high BP which is usually due to a secondary disease. Also, if BP is high above a certain limit it is significant regardless of if you took rest for 5 minutes and other precautions. Because if BP is high the normal BP regulating system should kick in and lower it regardless of the cause. With advancing age and hardened arteries this response becomes less optimal and you need the support of anti hypertensive medicines. You can see this in real time in patients under anesthesia. A young healthy patient would have an initial peak in response to pain or other surgical stimulus but they will be able to lower it either spontaneously or with minimal outside intervention. Whereas in older individuals much more effort is required to control and lower the BP. The general trend has been to treat both hypertension and diabetes early because the microvascular complications start much earlier before they become apparent clinically.
No, “everybody” in healthcare does not know this. I have learned to be skeptical and not to assume any particular level of statistical competence in the healthcare field.
Nurses/healthcare professionals often take the patient's blood pressure and heart rate just as soon as they enter the room after walking and moving about. Wait a few minutes and the measurement changes significantly, giving you a better indication of actual heart rate at rest.
I went in for a checkup and my doctor actually retested me after a few minutes because the first reading was unnaturally high. Hurrying into the office and the general anxiety of being in a hospital certainly raises it by a bit.
If they don't then the education system (and common sense) has failed them.
It's been failing a lot of people for a while then. At this point you can't assume competence.
I get the sentiment, but let me add one thing. Understanding statistics well is far from "common sense". In general, to operationalize statistics well, one has to both (a) train your mind quite carefully beforehand, and (2) slow down in the moment to make sure your rational thinking modes have traction.
I’m not sure how common sense factors in, but the education system has absolutely failed most providers that I’ve seen in the last 20 years.
Does the body of a patient under anesthesia react to (unfelt?) pain by raising blood pressure?
Wasn't there a recent article that said it was best to measure blood pressure lying down?
4-7 mm of inaccuracy is irrelevant.
> The only accurate measurements are direct measurements through an arterial catheter which is a very invasive procedure.
No. Accuracy isn’t all or nothing.
If one means “most accurate” then just say that.
Meta-analysis here: https://pubmed.ncbi.nlm.nih.gov/28750701/
There are also newer techniques, such as resonance sonomanometry: https://www.caltech.edu/about/news/caltech-team-develops-fir...
There's definitely a huge variance in blood pressure readings depending on posture, relaxation, arm position, recent activity, etc. If you buy a blood pressure monitor, it's really interesting to see how "random" a single reading at the doctors' is, and how large your fluctuation throughout the day is.
That being said, it really makes me wonder about studies that correlate blood pressure with other things. Is the blood pressure really being measured "correctly" in all those studies? Or not?
In other words, if your "true correct" blood pressure is lower than what the doctor normally takes, but then a lot of the studies are based on real-life "incorrect" higher blood pressures, then don't you similarly want an "incorrect" higher reading for consistency? Or are the studies always really done with far more accurate blood pressure readings, where the patient sits still for 5 min beforehand, keeps their legs uncrossed, is totally free of stress and anxiety, didn't exercise beforehand, etc.?
Another fun factor I learned about five years ago is temperature. My gym was offering a complimentary fitness evaluation, which among other things included a blood pressure test. The trainer was horrified to see 140-something over something equally terrible, and started explaining how she'd have to refer me to a doctor and advise that I refrain from strenuous physical activity, until I showed her a report from my annual physical a few days prior with 106/70. Turns out that walking to the gym in shorts and a T-shirt in late January causes enough vasoconstriction to really screw with some measurements.
I once had a similar high outlier blood pressure reading after a somewhat busy day followed by running through the city to my blood donation appointment. Who knew that BP is affected by external factors and doesn't stay constant throughout the day‽‽
Having a full bladder will raise your blood pressure.
It raises my heartrate as well. I know my bladder is full many times due to the heartrate rather than feeling my bladder. I'm not sure if others notice this. I assumed without looking at the anatomy that the arteries to the lower extremities are under pressure from the bladder.
I had a similar trip to the blood bank once: I rode my motorcycle from Palm Springs to San Diego, straight to the blood bank, on a cold January morning. As usual, they took my temperature. It was 95-something. They said, "Are you feeling alright?" I said, "Sure, I should have worn better clothing for the ride down here, but I'm fine." They conferred, then took my cold blood :-)
The first time I’ve seen an interrobang used in the wild!
No medical advice should be given on the basis of a single blood pressure test.
I've donated blood about a dozen times, my BP has been high on one or two occasions but only if it was a pattern after two or three times did they flag it up, and since it went back down the next time it was no longer a problem.
They did send me letters about the amount of ferritine in the blood though; the first time it was too high (probably due to having a thing for food that turned out to be high in iron for a while around that time) and they advised I see a doctor for it, but it went down on its own after that. And the last time it was too low, but that's a normal thing if you donate blood a few times (it was every two months for a while), they basically don't summon you again for six months.
TL;DR, a single measurement says nothing.
Any exercise will raise your BP by quite a bit.
> Is the blood pressure really being measured "correctly" in all those studies? Or not?
This is why you do readings three different times a day for several days. And why there’s instructions on how long to dust still before the readings, why you do three repeats with multiple minutes of wait in between, and finally why the averages of those readings aren’t just simple averages. But yes you always have to wonder about every study using self reported home readings if they follow the instructions or not, because it is tedious to do it correctly.
The reading process itself is a constant that you can't filter out by doing it repeatedly. Something squeezing your arm with what feels like the force of a hydraulic press surely doesn't have any weird side effects.
Anecdata, but I always get high anxiety from not being sure if the thing is actually still working properly or if it's just gonna keep pumping itself up until it explodes in my face or something. Not exactly rational but these sort of things never are. Looney toons ass machine.
"Something squeezing your arm with what feels like the force of a hydraulic press"
It shouldn't feel that crushing. I know it's common, but it shouldn't be. It's lazy/rushed healthcare professionals who only want to take it one time suing an automated machine and crank it to 200mm. If you actually put it at 140mm or take it with a manual sphig, it would read a "normal" person just fine without the crushing. The problem is, the people who are high around 130-140 need the machine at least 20mm higher and would need a retake, which means more time.
I have an automatic at-home blood pressure device, and it does the same thing. Not 200 mmHg, but high enough that I’d freak out if I didn’t know it was normal and would let up soon enough[1]. Did the product designers do that intentionally while still meeting a spec of “not panicking the user in a way that would elevate blood pressure” and getting approved for sale to non-professionals?
It seems like this is genuinely hard to work around in practice.
[1] I recall it being a staple of 80/90s tv, at least Beavis and Butthead, to have a character use an auto blood pressure device and freak out at being so clamped.
One alternative is a cuff that measures on the upswing, rather than the downswing. It does not tend to squeeze quite as hard, because it stops as soon as it has the systolic reading.
e.g. Omron BP7000
I have omron it has been at least 10 points lower then my other ihealth cuff. I even sent it in, they said was fine. Had the dr check it as well. It was always 10 points lower. I read that omron measures differently than the typical bpm.
To my knowledge Omron is considered one of the gold standards for home BP monitoring. Most of their cuffs measure the same old way, the BP7000 is one of the few models that do an upswing measurement. I've had both, along with periodic measurements at the doctor (I also do not get white coat hypertension). The Omrons have been in agreement with all my "official" measurements.
I have a 6-7 year old Omron brand device that doesn't do this. I can always tell right away when my BP is running high because I can feel the machine squeezing harder than normal to get the reading.
There might be a repeatability thing. Always give the full pressure then at least it's one less variable to account for.
Nah. Modern automatic cuffs are adaptive. They tend to first run up pretty low (like 150), see if there is signal. If not then they have to inflate more and more. They tend to determine where to start next time based on the last reading, so if it had the go up to 200 for the last reading it’ll start there next time. If the cuff is a vise, excluding operator error the most likely cause is actually having high blood pressure.
There is another factor that everyone is ignoring here. Some people are just much more sensitive to that kind of pain. If you Lymphadema, or especially Lipodemia, you are much more likely to experience a lot of pain even when a manual sphygmomanometer is being used.
The Omron BP7000 doesn’t hurt me that much, and I measure mine every morning and every evening. But it does hurt my wife, and she has both conditions.
Just to point, it's known that a sizeable segment of the population reacts to the pressure measuring process with increased blood pressure.
That anxiety is more present in the first of the readings than the last, so you get an indication if that’s affecting the reading too. You don’t have to be able to filter it out entirely to know if the reading has diagnostic value.
I would trust the self-reported home readings more than those taken by professionals, because they're probably happening more often and under less stressful and exceptional circumstances.
> This is why you do readings three different times a day for several days.
What good is this if my monitor is not as accurate as the one at a doctor's office? It's not like my doctor would take my monitor's readings over his.
Find one that is accurate enough and crosscheck it with the one at the doctor by taking regular measurements so you get an idea of trends rather than absolute values. Doctors do know about white coat hypertension - it's not a myth. There's no reason you can't do your own experiments with consumer-level blood pressure monitors from reputable manufacturers. In fact, it was my mother's primary care provider who recommended she buy one for home use.
This is what I did with a US$10 pulse oximeter (a Contec CMS50M from China) when my dad ended up in ICU last year, and it was pretty much bang-on with its readings. I've also tested my pulse oximeter on plane trips and know it will drop below 90% when the air is thin (and rise up again if I do some deep breathing), and therefore know it isn't always stuck at a high value.
Search PubMed for "The Accuracy of 6 Inexpensive Pulse Oximeters Not Cleared by the Food and Drug Administration: The Possible Global Public Health Implications".
You might be surprised. "White coat hypertension" is well-known. Someone with a reliable set of readings from home would be more convincing than someone who says "I get it read at Walmart/CVS once a month and it's ok".
Your doctor's office's monitor isn't incredibly accurate. If you want accurate, you need a mercury sphygmomanometer to measure the pressure. Unless fundamental properties of the universe have changed, it will also be comparable to any other readings taken with mercury.
And it has to be in retrograde.
That's a complicating factor, but one that we can usually calculate.
My doctor did. My blood pressure was slightly elevated in his office and I said it happens at every doctor. He said to get a home monitor, test 3 times in the morning, 3 times in the afternoon for a week and bring in the results at the next appt.
Don't worry, your monitor is good enough for the purpose of screening for hypertension. Truth is the exact values don't matter much for this purpose. Only thing that matters is the fact that people die less and develop less complications when treated based on the results. They are still useful even if the figures have some error in them.
Medicine is just statistics.
It varies of cause, but here the doctor just sends you home with a monitor exactly identical to the one they use at the office. But it’s not like there’s a world of difference to the ones you could buy yourself at a resonable cost.
Either it's accurate enough (most cases) or it is too wrong
Unless it's a wrist model, it should be ok.
My wife had a Cryo Chamber Therapy for a few weeks and had to measure pressure and pulse before each session so they let her in. After about a week she was refused entry because her pressure was too high (when she measured it at home - it was normal).
Since then she had problems getting admited every time, and she started to fear the measurement (she had to drive there during work and do overtime later).
She started arguing with the guy and wasted like 5 days driving there and back during work without having another session because the pressure and pulse were too high (despite both being OK at home).
Eventually she went to another person in that hospital to measure her pressure. It was perfect. But when the guy near the entrance to the cryo chamber measured it - it was too high to let her enter.
They tried different instruments and the difference was the same. When the guy measured it - it was too high. When somebody else measured it - it was fine. Finally they let her do the cryo chamber without the guy permission :)
We assumed the difference was just that she was anxious and frustrated when she's seen the guy, but now I wonder if the difference was the position in which he measured the pressure.
Had the exact same thing happen when I was doing a Ketamine therapy thing a while back, and I definitely think the anxiousness about the reading had something to do with it.
I've always had perfectly okay blood pressure whenever I have it done at a regular doctor's appointment, so I think knowing that the reading actually matters definitely increases my blood pressure. Ended up getting a doctor's note saying "they don't actually have high blood pressure they are just reacting normally to possibly having to be sent home and reschedule" more or less.
I think this is a well-known thing, being apprehensive about having the measurement being taken can influence the result - https://en.wikipedia.org/wiki/White_coat_hypertension
I get anxious when taking blood pressure as well. There are techniques your wife can try before entering the cryo-chamber look up the 478 breathing technique. I developed a white coat blood pressure readings over the last several years measuring a stage one or stage two hypertension at my last doctor visit. I use the 478 breathing technique and my blood pressure readings are normal at my last dr visit.
When my heart went to hell, I bought a blood pressure monitor. Before I left the hospital, I had to agree to religiously test my blood pressure three times a day at the exact same time. Anything beyond that was a bonus, but to provide useful data I needed those three readings a day.
As my cardiologist explained, 39 year olds don’t randomly end up spending a week in a cardiac ward so he needed better data to form a holistic treatment plan.
I found that that the measured BP was consistently significantly lower if I didn't look at the device's display while it was doing it's thing. This at home, with a quality device, after doing it many many times.
Yes, i experiment with eyes open/closed as well
As long as blood pressure variance is randomized then you’re getting a signal, and that happens when everyone is measured in a similar way (or randomized to different ways). You don’t need perfect precision.
What you don’t want is to make everyone who, say, smokes wear the cuff while standing up while everyone else gets cuffed lying down.
> and that happens when everyone is measured in a similar way (or randomized to different ways)
But that's exactly the issue -- that the similarity or randomness is one way for one study, and another way for another study, because of culturally different sets of nurses and/or patients.
In other words, you're right it's not affecting results within a study, but it makes comparison between studies questionable.
And it makes it equally questionable whether a study's results apply to you, if your signal is 10 units off of a study's signal, and occurs across a cutoff that determines whether you should take a medication or not.
> Is the blood pressure really being measured "correctly" in all those studies? Or not?
Probably incorrect in most studies, especially large population ones that influence treatment guidelines.
It’s academic and doesn’t practically matter though.
The pathogenesis of hypertension related disorders (kidney failure, heart failure, stroke etc) is well known.
It’s not in doubt that sustained hypertension is bad, that there is increased risk with higher blood pressure and that patients with high blood pressure undergoing treatment suffer less of these bad outcomes.
My doctor was handing me, hypertension, pamphlets, and talking about medication.
Finally realized, that I was habitually late, getting to my appointments and always taking the stairs.
Don’t do that.
iOS voice dictation?
Yea. But it’s mostly good except for the commas
With pauses to keep his BP low.
Also doctors and nurses are known to do an abject awful job of measuring bp according to the defined procedure. It’s usually way off when taken clinically.
Ars article here but there’s plenty in pubmed too.
https://arstechnica.com/health/2024/10/your-doctors-office-c...
[edit] The prep guidance is…
> You must not eat, drink, exercise, or smoke within 30 minutes of a reading. You must have an empty bladder. You must sit straight up in a chair with back support. Your legs must be uncrossed and your feet must be flat on the ground. The arm to be measured must be rested on a flat surface so that it is at the same level as your heart, not lower, not higher. You must sit calmly, without talking for five minutes to relax before the reading. When it's time, an appropriately sized cuff should be wrapped around your bare upper arm, right above the elbow; it should never be wrapped over clothing. At least two readings should be taken, with the average recorded. Ideally, readings should be taken in both arms, with the highest readings recorded.
When was the last time you got it measured properly? Literally never for me in a clinical setting. I don’t know why they bother honestly.
What's the point of taking your blood pressure if doing any of these things causes significant variance? I'm not meditating at home or out and about all day. So why does it matter what my blood pressure is in one single state? What if I'm in an elevated state all the time? What if I never am? It makes it really hard to believe that blood pressure readings are anything more than nonsense.
If you're doing a double leg press (especially in conjunction with a Valsalva maneuver) you can get an instant BP reading as high as 320/250. If that's your idle BP then you're not long for this world lol.
If your BP - measured in a specific and consistent set of conditions - is elevated vs baseline then you are at an increased risk for a set of medical conditions. Researchers could have picked any set of conditions to establish that baseline but I assume that idle is easier to standardize on than e.g. double leg press with 3 RIR. It's not which condition per se but rather that it's the condition researchers aligned on and studied.
The problem is that if the risk is established based on your deviation from the baseline, then you must be measured in the same conditions under which the baseline was established otherwise the results don't mean much if anything at all.
The idea, in theory, is to measure your "minimum" or baseline blood pressure.
That your activities throughout the day add variable amounts to the baseline but never go below it.
It is a very good question though -- some people have activities/jobs/lifestyles where their BP is significantly elevated all the time. So surely you would think that must matter?
And what's the typical variance (from "actual") for a "usual" reading?
10-20 mmHg.
https://www.ncbi.nlm.nih.gov/books/NBK482189/
> Smoking within 30 minutes of measurement can raise the systolic blood pressure to 20 mmHg
> a distended bladder can increase systolic and diastolic measurements by 10 to 15 mmHg.
> Sitting in a chair lacking back support can raise systolic blood pressure to 10 mmHg, and a similar increase is observed when both legs are crossed.
> Talking/listening during measurements can increase systolic and diastolic measurements by 10 mmHg.
The major exception is cuff placement over clothing which is noted to vary results by up to 50 mmHg but doing that is stupid anyway and makes you fail medical school.
For me, the first reading is usually higher (by 20-30, even after a long rest period) and subsequent ones get lower and lower as I calm down from the initial worry about whether I will get a high reading or not.
At the doctor's office / hospital I try to tell them this, but they tend not to care. I think they know it varies a lot, they know about psychological effects, but i) they anyway take it much less seriously than overthinkers like me and some fellow HN-ers would imagine and ii) they may prescribe something and anyway expect it not to do much, and also expect the patient not to follow through with taking it properly etc. Honestly, the whole thing is quite a farce. The painful truth is that generic lifestyle improvements are the biggest bang for your buck, instead of worrying about getting exact and precise blood pressure readings.
The other similar big thing is routine blood tests for deficiencies and cholesterol, iron etc. It can also have huge variance over the year, and often people only do it every one or two years and take it as this extremely solid evidence that you need to take this or that medicine. If we were truly serious about this, we would do several tests, separated by weeks, done with different kit manufacturers at different labs etc.
I think the reason for not doing more thorough testing is implicitly admitting that the results aren't really all that actionable and improved precision doesn't really improve treatments because we have no idea what to really do with the results. There are studies showing correlations/causations of certain interventions on specific markers, and those markers are in turn correlated to some outcomes, but often the "evidence-based medicine" doesn't follow the full chain towards the actual outcome.
The other big reason for not measuring more times is the same that a man with a watch knows the time, but a man with two watches is never quite sure about it. In other words, if you got a test and had a result, you can document this and all is fine.
Good question, for myself personally (anecdotally) I got systolic of 145-ish in the doctor's office and 120-ish at home. This was validated by a medical take-home 24h cuff.
Probably never, I have really long arms and they usually take it just barely above the elbow also. I have always been on the higher end even when in my 20s and training/dieting for athletic events.
Used to flummox me until I bought my own meter, they can be like $30.
Doctors recognize that non-invasive BP measurement is an imperfect screening tool. Anybody worth their salt isn't getting worked up about these level of details, because it's largely a waste of time and effort. The solution to an error prone screening tool is not to repeatedly use the screening tool. You move on to more accurate and focused methods of testing.
> The solution to an error prone screening tool is not to repeatedly use the screening tool.
It can be. Repeated in office blood pressure measurements increase sensitivity and lower specificity. It's not as good as 24 hour monitoring but sometimes that's the best you've got.
> You move on to more accurate and focused methods of testing
Yes, AFTER the imperfect tool gives you something to worry about. So you still need the imperfect tool, which is what I think a lot of people are missing in this conversation.
Kaiser measures BP on every visit and arm position seems like the least of their worries:
- no rest period before measurement
- measured through a medium-thickness sweatshirt sleeve
- cold hospital hallway
- no back on the chair
- no height adjustment on the chair
- no real surface to rest your arm on (They usually use the handle of the equipment cart that the BP monitor is mounted to)
- Zero attention to cuff positioning/orientation
I've come in at 160/90 but went down to 120/80 after rotating the cuff 1-2cm and resting for a few minutes. Manual measurements from the doctor are usually more accurate.
This is why it is better to take three measurements and do an average every time to minimize errors.
The studies on correlation probably have a large enough sample size to become statistically significant - i.e. you have to read the "Method" section to find out how reliable it is, this requires certain kind of statistics and/or scientific background.
Reading around (e.g. [0]) it sounds like variance isn't something researchers care for, probably with the assumption that screening with a higher value is better than missing an issue from a lower value.
We see the same for body temperature (speed and convenience is usually prioritized over accuracy) and weight (2% variation is largely accepted). Afterall guidelines are already off as by definition, as they don't account for individual circumstances, so perhaps aiming for accuracy is useless in most settings.
[0] https://www.mayoclinic.org/diseases-conditions/high-blood-pr...
Kind of wonder the same thing about BMI and water composition. Your body weight can vary by up to 10 pounds depending on how much water you're retaining. I've never been able to find information about the composition assumed or measured when coming up with BMI numbers.
Granted I don't think the ultimate effect is huge, and you can eliminate it by weighing yourself daily and taking an average. But most people don't do that, and a spot-check at a doctor's office certainly can't do that.
> I've never been able to find information about the composition assumed or measured when coming up with BMI numbers.
BMI is just weight divided by height squared. No distinction is made between type of mass. Muscle mass, fat, bone, water? BMI couldn't care less. It sums all that stuff up into a single value.
Think of it as a number that roughly correlates to disease. There will always be false positives and false negatives. False positives are acceptable. We want to minimize the number of false negatives.
There are nearly ten billion humans on Earth. It is not possible to fully evaluate every single one of them. Gotta run a SELECT statement. Filter them based on some criteria, and fully evaluate those that match. BMI isn't perfect, but it takes less than one minute to measure the variables and compute it. The equipment required is cheap and easy to use. Speed, efficiency, cheapness and ease are extremely important factors when you're applying this at national scales.
Patient might turn out to be a physically fit 100 kg 1.7 m 34.6 kg/m2 body builder. That's alright. Our objective is to make sure the obese and the malnourished can't escape the sieve.
You could probably get to a better generalisable number by slapping waist circumfrence in there as well.
Absolutely. Waist circumference should be and is considered as well, especially when evaluating obesity and its comorbities.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7027970/
The combination of BMI and waist circumference is even better.
I guess it depends on the study. If it is just comparing between groups, the conclusions probably still hold if they consistently measured blood pressure in the "incorrect" way. If it is something like "85% of Americans have high blood pressure", then probably the conclusions are incorrect because they are comparing the "correct" baseline against an incorrect measurement method. There are also other ways to measure blood pressure, like recent smartwatches - so read the methods section carefully, I guess.
> are the studies always really done with far more accurate blood pressure readings, where the patient sits still for 5 min beforehand, keeps their legs uncrossed, is totally free of stress and anxiety, didn't exercise beforehand, etc.?
In situations where blood pressure really matters, we aren't playing around with the cuff and hand positioning. The patient gets an art line.
Oddly, at least a decade ago, at least one Bay Area hospital stroke protocol required manual BP readings with a sphygmomanometer. And the patient had an art line.
Not sure if they didn’t have the equipment for art blood pressure or what, but good BP readings were important. And they had all the fancy equipment. Patient presented with an ischemic stroke, and was getting a stent + thinners, so anything problematic was likely due to something immediately life threatening.
They didn’t want an automatic cuff system because it could cause something to burst with the pressure ramp up. At least that is what the surgeon said.
Source: I was the EMT-B on his clinicals who stayed with the patient in the OR while he got stented and took readings every 5 minutes because none of the nurses were ‘current’ on the manual cuff. or so they said. I was pretty fresh, and was pretty good at it at the time, but I think they were just making excuses now haha. I held his hand through the procedure to help calm him down too, which seemed to help a lot.
Patient 20 something that day. Emergency Rooms are quite an experience. I volunteered for Halloween Night, which added to it I’m sure.
PS. Watching the Dr install the arterial catheter (or maybe it was a port?) in the ER was wild. Literal stream-of-blood-shooting-across-the-room-and-spraying-on-the-wall wild. Never seen anything like it before or since. I was glad I had my safety glasses on.
My understanding from people who follow the literature is that the studies are done with the recommended procedure, 5 minute wait and all.
Exactly, this is my concern as well. They say you have to be seated for 5 minutes at least, completely relaxed, not hungry, not having to go the bathroom, in a quiet a room, it must not be too hot or too cold, with both your feet on the ground, before you can have your blood pressure measured, otherwise the reading could be 'artificially' high. Really? It seems to me that if you do all these preparations, the reading will be artificially low, since such conditions are nothing like the conditions that you'll typically find yourself in through the day in your everyday life.
The goal is to get a clinically relevant measurement, captured at rest under specific conditions, not a measurement that's representative of a random moment during everyday life.
We're also treating people for things like blood pressure somewhat statistically rather than individually.
The studies say, people who have a blood pressure measured this way, that is above X, have an N% higher chance of dying M years sooner of A, B or C than people who measure under Y. If you treat with medication Q it lowers blood pressure, measured this way, by Z points, increasing lifespan by W QALY.
Are you treating people who don't need to be treated and missing people who do? Could you achieve better results with continuous, invasive blood pressure measurements while the patients engage in every day life?
Probably, but then you're increasing the cost of both the study and the public health intervention exponentially for gains in the margin.
But if the measurement isn't representative of your actual blood pressure what's the point of taking it? It's completely non-informative. Another problem is that even under very controlled conditions, I sometimes find big differences in blood pressure from one minute to the next.
Yes, I was thinking the same. If everyone is measuring heart rate under similar conditions, and then correlating that heart rate with other factors, is that perhaps alright? Can we factor out the "error" to get a working baseline, even if the measurement isn't really heart rate at rest?
I doubt it, frankly. No one is controlling for these conditions. The easiest thing you can do is to wait a few minutes for the patient to relax after entering the examination room to get a reading at rest.
Quite a few people here report getting anxious even when taking their BP themselves:
https://www.innerhealthstudio.com/phobia-taking-blood-pressu...
I'm one of them. I bought a device with memory and covered the screen with a piece of card. Then I take BP for two weeks and ignore the first few days' readings. I seem to get used to it after a few days. This gets me readings that are very close to 120/80.
I've had anxiety about blood pressure ever since running for an appointment, while being on the first day of a new job when I was really amped up, and so (of course) had a dangerously high reading. I still remember the guy's eyes widening as he looked at the screen. Ever since then I've hated having BP taken and I can feel my BP and pulse increasing the moment I step into a doctor's office. Fortunately my doctor understands and doesn't try to push pills on me.
I wish there were some way of measuring BP without knowing it's being done. The act of measurement can greatly affect the result, which is counter-productive in several ways (not the least of which is un-needed anxiety).
York Cardiologist on Youtube is good on BP, and why apparently high BP should not automatically mean pills, although undoubtedly it sometimes should. (Usual disclaimer: this is not medical advice, ask your doctor about your specific situation.)
I remember when I was a kid, the doctor thought that my blood pressure was too high. Of course, I was just anxious because I knew they were going to give me a shot. What kid wouldn't be?? He took it again after I got the shot and it went back down to normal.
Try the 4-7-8 Breathing technique while you are traveling to and right before you take the reading. Also just focus on something else like counting things on the wall while they take it. Mine has been high when I take it at the Dr office. But at home fine. I think tried the 4-7-8 Breathing technique this last time and it read normal at the dr office.
Replying to my own comment, but it looks like there's at least one device on the market that measures BP without the wearer knowing it's being done, the Aktiia Optical Blood Pressure Monitor.
Cost about $250-300. It's not available in the US right now officially, though it's cleared in several European countries. I don't know if it's legal to import. If it is, I may well do so.
Regrettably it has a cloud connection.
I take BP readings for someone who gets anxious about them too. The system we've arrived at is that I play music that relaxes them during the readings. They don't look at the numbers. The first one will be high, so I usually ignore it. I take several readings, look for a couple of consistent ones, then discard any outliers.
Trying to relax always makes me more anxious since it reinforces the idea that there's a danger to be avoided. Over time I've learned the techniques of ERP, which basically does the opposite.
Yeah I'm one of them. I developed a full-on anxiety disorder after my diagnosis with high BP to the point where I would get panic attacks just sitting in front of the device.
At the same time I would became obsessed with measuring BP and pulse...
My current solution besides anti-depressants and therapy is just ignoring it and trust in the pills from the doctor.
Right now I'm thinking about trying something like the Aktiia wearable to get some measurements without me knowing...
> My current solution besides anti-depressants and therapy is just ignoring it and trust in the pills from the doctor.
Look up ERP (exposure and response prevention) therapy, then apply it to your fear of BP. I did that, it helped a lot.
I spent several weeks trying to get a dental procedure, where the dentist flat out refused treatment because my BP was high, and every subsequent rescheduling was higher and higher and higher every time. Got a note from my PCP - my dentist still wouldn't do my crown, and was insisting that my PCP do a full screening and review. My dr just gave me some xanax to take before going to the dentist, and never had a problem since. Recently moved, and just straight up asked if I can sign a waiver or something for them to not take my BP at the dentist - new dentist was like "no problem"
I've never looked into research on this subject, but I always assumed this was already well established and known - and it was definitely somewhat already either known or at least believed to be the case:
- Every doctor in the UK I've ever seen do a BP test has made sure the patient's arm is in the right position, rested on a table/cushion if needed, in a way that matches the findings in this study (and while I've only needed my own BP tested once or twice, I've sat in on many, many doctors while they tested the BP of family members of mine).
- My home BP device is a Braun wrist cuff (and is at least a few years old), which has a built in feature that uses an accelerometer to guide you to raise your arm until it's at an angle which means your wrist is at the same level as your heart (this one: https://www.cora.health/guide/best-blood-pressure-monitor/#1... )
I've used the Braun wrist cuff, and while the heart-level feature is cool and perhaps good enough to mitigate position issues, I found that it was very unreliable vs. cuff measurements.
What do I mean by "unreliable"? Two things - (1) internally consistency for the given device and (2) not closely correlated to the arm cuff measurements.
My method: I would wear both devices and take a series of readings (like 5+ from each in a session, and did multiple sessions a day).
My results: while the cuff readings of course had some minor variation in of themselves, they were largely consistent with themselves (i.e. clustered around the average for the session) whereas the properly-positioned (according to the heart height feature) wrist measurements were all over the place showing big swings between readings and a wider dispersion from the mean.
Then there was the issue of did the wrist average measurements roughly correlate to the cuff averages - and not only was the answer "no", it would vary whether it was higher or lower. Which is a shame - it's ok if it was, say, overstating things by +5 mmHg but overstating at that rate consistently (because then you could mentally adjust the outputs); but when it's inconsistent you're just left scratching your head.
As I wrote about in another thread, the continuous wrist monitor Aktiia that I've been trying gets correlated explicitly to an arm cuff and seems far, far more accurate and consistent than this Braun device. It uses optical imaging of your wrist's blood vessels vs. physical pressure on a cuff.
All this to say - test for yourselves! Try multiple arm cuffs, even. While the exact numbers are less important than the trend, you need a device that you can trust w.r.t. output.
It's possible you were unlucky and had a dodgy device (or it's possible luck has misled me to believing mine is better than it is).
I chose it because my GP recommended that in his experience it was accurate, and in addition to testing it against two brands of normal upper-arm cuff (consumer) devices that a friend and a relative had, I also took it when taking my dad to his GP who the previous time had expressed interest in the wrist-based device I'd mentioned using on my dad, and she tested it against her two devices (one an electric upper arm cuff, the other an old-school manual upper arm cuff that involves squeezing a rubber thing on the end of the hose to inflate it and a manual clock-style dial for readings).
We didn't detect any unreliability in it compared to any of those 4 devices (two consumer, two NHS-approved & doctor-owned) - all 5 seemed equally reliable (based on our not exactly lab-quality testing, but still we weren't lazy enough to do single readings or anything like that).
Interesting thanks for sharing - maybe I'll try again with another device.
Can you trick the Braun device into thinking your wrist is level with you heart?
Yes - it's just a digital spirit level of sorts, that instead of being calibrated to align with the ground is calibrated such that, based on typical angles and dimensions of a human body leads to the wearer holding their arm up in front of them with the device in line with the heart.
Here's what it looks like, the device won't start until you've got the ball to hover in the middle circle, but it has no way of knowing if you're doing it properly or if you're lying down or leaning your body forwards or whatever else would mean that the angles no longer put it level with your heart.
https://imgur.com/a/pV6xcpc
edit to add: so when used correctly it looks roughly like this - https://m.media-amazon.com/images/S/aplus-media/vc/573a171a-...
Basically the same logic as, for traditional upper arm cuff devices, giving the instruction to rest your arm on something next to you that allows your forearm to be resting both comfortably and straight, parallel to the floor - which again, doesn't technically mean the middle of your upper arm must be level with your heart, but since nobody would really be comfortable putting their forearm flat on a low down coffee table or a high up standing desk it works as a proxy that's simpler than asking people to think about lining anything up with their internal organs.
I am not a doctor and this is not advice. This is a standard medical test I have completely given up on any doctor to perform accurately. I do it myself at home once or twice a month. I do it with the same device, in the same chair, at the same desk, the same time of day, after I’ve ate and drank the same thing. Yes, I still let everyone take it because it’s typically a precondition of receiving care but my readings at home are completely different and give me a more accurate data point that actually makes me feel good about the progress I’ve been making on my health.
I’m actively looking for more healthcare I can do this way. I trust my data and it all coming together on the safety of my personal device. We don’t need doctors with extremely limited datasets to do this and try to find obscure correlations for us.
>This is a standard medical test I have completely given up on any doctor to perform accurately. I do it myself at home once or twice a month. I do it with the same device, in the same chair, at the same desk, the same time of day, after I’ve ate and drank the same thing.
You are assuming the average patient is this careful about measuring their BP, or anything about their health. You are also assuming the average patient measures their BP correctly, which is obviously untrue as evidenced by some other comments on this post. You are also assuming patients always tell the truth about their own measurements.
>We don’t need doctors with extremely limited datasets to do this and try to find obscure correlations for us.
I don't understand what you mean by this. None of us finds obscure correlations with limited datasets. We don't diagnose someone over a single BP measurement.
> We don't diagnose someone over a single BP measurement.
Yeah I feel like no doctor of mine has ever been the type to do that. My current PCP wouldn't prescribe meds for hypertension until after I took my own BP at home for a month (it was not catastrophically high when measured at his office, he might have taken a different approach in that situation).
Even with a catastrophically high measurement, no doctor would diagnose with a single data point. At worst, they would ask the patient to measure at home multiple times a day, after teaching the correct method of measurement. At best, they would do an ambulatory monitoring.
False. I went into a first visit at a doctor office one time and after spending about five minutes total with me he sent me home with a BP Rx. No mention of verifying it with home readings to make sure I really need it and he didn't even bother giving me standard advice like lose weight. Most other doctors did only slightly better. Insurance only reimburses for like 10 minutes of their time, half of which is spent updating records, so it's unsurprising they don't have time to properly handle your problem.
Maybe not a diagnosis, but dependent on history if my patient is throwing repeatable >200 systolic that's probably not one I'm going to just sit on waiting for repeat measurements.
I got started in BP medication after like 2 readings.
Same here. I feel like the type of physician who comments on HN may not be representative of the average PCP.
> after I’ve ate and drank the same thing
My doctor recommended doing it first thing in the morning, before eating or drinking anything. That's probably an easier way for the general population to establish a consistent baseline
It's not only easier, but the actual correct way of doing it. That's why your doctor recommended it.
> typically a precondition of receiving care
I've achieved exciting results by flatly refusing vitals checks at each and every medical appointment. Especially psychiatrists. The PCPs always gamely admire my self-reported histories and graphs, commenting how nicely the trend line goes down, and then completely dismiss the results in their clinical notes.
However, I did lock horns with a particular chiropractor. I filled out the "pre-existing conditions" form with candor and honesty. I permitted a BP check. (His method was 100% manual sphygmomanometer.)
Then he informed me that he wouldn't touch me until my BP was controlled and normal. Yes, a chiropractor, not a cardiac surgeon. Geez.
In the past, I've tried to avoid submitting to blood draws and labs, because those are 100% fishing expeditions, and not actually attempting to diagnose a complaint or symptoms. (They love to misdiagnose hypothyroid or diabetes so they can begin destroying your endocrines.)
Unfortunately, clinics do these orders on a schedule, so if you avoid labs for a while, the orders simply pile up until they contrive to get them all done. I couldn't win. Still putting off colonoscopy: 2.5 years late, and counting!
Amazing it’s like you’ve figured out the optimal strategy of still spending the same amount of time going to the doctors but getting as few benefits as possible.
I’m pretty sure you can decline care and get second opinions no matter what.
I don’t know your family background, but I have quite a few older male relatives who died from cancers that if caught early have high survivability. They were all suspicious of the profit incentives of the medical system and felt they knew better or were tough enough to not care. My grandfather had a heart murmur, so he used that as an excuse to never go to the doctors. “They just want my money I already know my heart will kill me soon so why bother”. He died of colon cancer. I’m sure they all regretted it.
>Still putting off colonoscopy
I hope you won't regret putting it off.
>They love to misdiagnose hypothyroid or diabetes so they can begin destroying your endocrines
Yes, my favorite pastime when I'm bored of treating "actual" diseases.
I fail to understand how a well-educated group of people (aka. HN) can be this against the scientific method.
Perhaps I'll go for "Cologuard" instead?
https://youtu.be/Mu12X2cu6Y0?si=bn17f2Lbx9SQUE9y
Every single health related thread is like this. Dude thinks because he's been programming JavaScript for 10 years he's a literal genius. It's pathetic.
He's intentionally refusing care and just living his life. I don't agree with that, but I do understand it.
We all shuffle off someday. What's the worst that can happen? He dies?
If it wasn’t actually bothering him, I doubt he would be spending so much time and effort dodging it. Either ignore it (actually), or just do it, eh?
Instead he seems to be intentionally playing a high stakes game of chicken. Weird.
No, his quality of life and mental state is severely impacted for years if not decades at a time and he slowly, and very painfully, dies.
My father said the exact same thing about smoking. What's the worst that can happen, I die? Oh no - the worst that can happen is you living far too long.
Modern civilized countries pay for healthcare with taxes. That costs everyone more with his decisions.
Super preventable stuff too. "Itchy mole, prob nothing." Ope, it's a melanoma and has spread everywhere. You have 6 months to live.
Dying young six months after diagnosis might be cheaper for society than a long malaise during old age.
I intend not to die of chemotherapy. And no, I shall never regret being a prudent steward of taxpayer resources. Let's consider the collective good over an individual's selfish longevity.
What would Mr. Spock say about "The Good of the Many"?
If those involved are in the US, it’s a trust thing.
This isn’t the fault of medical professionals, but rather a system optimized for minimum risk and maximum billing.
For example, my adult son recently went through a bout of rectal bleeding. He sits a lot in his job and we assumed it was hemorrhoids.
It was a Saturday so rather than wait we met up at the local urgent care. They did an external exam and decided he needed to go to the ER. No, it couldn’t wait. We had to go right away.
So we went across the street to the ER and took up a bed for seven hours waiting for a CT scan and results. The CT scan showed no active bleeding or any other cause for concern.
At this point, it was 2AM. The ER doctor suggested we allow our son to be admitted so that they could accelerate a colonoscopy on Monday or Tuesday. Yes, that’s 2-3 days in a hospital room just so we could avoid outpatient delays.
Now, keep in mind, there are no other symptoms. He feels perfectly fine. The CT scan shows no active bleeding.
To us, admission seems like overkill. The doctor isn’t much help. They are mostly exhausted and also exasperated at “the state of health care in this country.” We try to be empathetic but more or less it feels like they are holding back.
So what to do? Well, my son made his own decision - we left. The next day, I called in a favor with a GI doc I know. We were able to get a colonoscopy 10 days later. Guess what? Internal hemorrhoids.
This is irritating enough, but what is even better is that we could have had that answer in 15 minutes if someone had pulled out an anoscope. Sure we’d likely need an colonoscopy as a follow-up but we could have been out of the system very quickly. We could have freed up that bed in the ER. Heck, we didn’t even need to be in the ER at all. Oh, and 10 days of needless worry would be gone.
I asked a hospitalist I know why no one thought to just have a peek. The answer? Oh, they definitely thought about it, but no one uses anoscopes these days. The preferred route is a colonoscopy. Why? Well, a colonoscopy is a better diagnostic tool, but frankly it also happens to allow for better billing.
And boy, oh boy is the billing good. For the hospital alone, we’ve got upwards of $6K in billing. Who knows what the colonoscopy will run. We have good insurance but to cover the deductible I’ll likely be out $2K.
Naturally, I’ve already called the hospital and asked them to conduct a billing review, which will be followed by a medical review. The result will likely be a claim by the hospital that all procedures were followed correctly, which is technically correct. They did it all by the book, wasted an enormous amount of time and money, and irritated all humans involved.
Anyway, this anecdotal story might explain why well-educated people are suspicious of modern medical practices (at least in the US).
FWIW, I’m in my mid-50s and I’ve not had a colonoscopy either, and I won’t be getting one. It isn’t that I don’t want to take care of myself but rather I can’t afford to actually know if I’m sick. In the end, squeezing a little extra life out isn’t worth the financial tradeoff for my family in the long run.
How does your adult son feel about his father posting extensive public comments about his anus?
Given that he is also an engineer I doubt he cares. Everyone has one.
But why go to these practitioners if you don't trust them ? Nobody should be forcing you. Is it because you want access to treatment solely on your own terms ?
Nobody is "forced" to get health care in the United States, [except once you're unconscious, insane, or incarcerated, and the ambulance arrives] but what are the penalties if we don't? A PCP is the only one who can route me to a specialist if I really needed one. If I broke my leg again, or had some other emergency, it'd be nice to have a followup with someone who already has us on file, rather than trying to get past all the gatekeepers for an initial visit.
Every insurance company will urge their customers to establish and visit the PCP on the regular. Every social services agency simply assumes... demands... that citizens have a relationship with medicine and that we dutifully visit the doctor to keep up on health issues. It's outright heresy and treason to say that you won't participate at all.
A physician is the only one who can keep records relating to disability cases. A physician is the only one who can write me a note if I'm unable to work. Eventually you'll need to release medical records to a third party in order to access benefits or qualify for something, so those records had better pre-exist! A physician is the only one who can diagnose or treat any disease, so what else would we do if we got truly sick?
John 6:68
I understand what you say, and there is some truth to it. However it's also justified that society asks something in return for societal benefits. That's pretty much the foundings of insurance. The extent to which that should go is debatable, of course.
> They love to misdiagnose hypothyroid or diabetes so they can begin destroying your endocrines
Im sorry but as a doctor this made me crack up. I don't know what it is about HN that makes people jump into every medical thread and say really absurd things. Skipping screening tests isn't one-upping your PCP. You just get to play harder with specialty when stuff starts to break. Good luck buddy.
It's not just medical threads, it's tech too. You (probably, I'm assuming) just don't know the tech as well as you do the medicine, so it doesn't stand out as absurd to you.
I have expertise in both. I think the difference is that when moving from the highly rigid world of medicine into tech, I expected the varied level of skill and knowledge that exists. It just throws you off seeing people in tech with no background in medicine talk about medicine like they know it.
Most of my closest friends are docs. A couple of times at a brewery I've had them read some braindead takes from here for laughs. The people here making wild comments on the architecture of o1 or whatever don't get the same reaction from the crowd.
Fair (and very cool!), sorry for the assumption.
I see people speaking complete falsehoods about things I have material knowledge of here, and either don't have the energy or the latitude to correct them.
And those reactions to (e.g.) o1 speculation are happening in (e.g.) OpenAI, I'm sure, haha.
Lol.
Hopefully you get lucky. Why address cancer, insulin resistance or stroke risks early?
Blood pressure measurements at the doctor are the bane of my (medical) existence. Mix minor white coat syndrome with time blindness and you suddenly have high blood pressure because you barreled up the stairs to the second floor office moments before the nurse took a reading.
My doctor was initially befuddled because by all other metrics I am in good health, but it’s amazing how you can go from 90/55 at home to 140/75 at the office. We do the measurement at the end of the appointment now to varying success.
Literally the first year of medical school, we were taught to let the patient rest for at least 5 minutes before taking vitals, while also asking about recent exercises or caffeine intake. This reduces the likelihood of a mistake, but white coat hypertension is still a thing. That's why we also teach them/relatives how to correctly measure BP on their own and ask them to measure it at home, preferably after waking up before eating anything.
My wife has one specific guy doing the measurement that she hates and when he measures her pressure it's like 10-20 higher.
It's also the guy that measures pressure before letting people enter to the cryo chamber, so she spend about a week rescheduling and arguing with him to let her in.
When she went to another person at the hospital her pressure was perfectly fine, and switching the instruments didn't helped - if THE guy measured it - it was too high - when it was somebody else - it was OK, no matter the instrument used :)
Definitely possible. Blood pressure fluctuates during the day. Activation of the sympathetic nervous system causes the BP to increase. So technically the measurements were "correct", but it was misleading because when talking about BP we normally mean "resting BP".
No doctor or assistant bothered to tell me about the impact of caffeine. I had a few borderline-high readings over a few months and was concerned until I realized I was drinking my normal 2-3 cups of highly caffeinated coffee just before these visits.
Weird, I ride my bike to the doctor, my heart rate is often elevated from the ride and my blood pressure is still normal (barely above low - though I've had enough different tests over the years to believe that exercise is having nearly zero effect)
I'm convinced most people take BP wrong.
Here's how:
Lie down on a bed on your back, and put the cuff on your arm and get the 'button' within reach of your finger to turn it on. Then completely relax (and DO NOT move) with soft music or whatever. Then without moving your body at all, after 10 minutes (at least) push the button to start the pressurization and reading.
This gives an accurate reading and is often DRAMATICALLY lower than if you don't do it this way. I was convinced I had super high potentially life-threatening BP until I learned this.
Now if you want to see I'm right, get up and walk around some and then sit back down and take another reading. It will be noticeably higher, because your heart starts pumping harder even from minimal movement.
>This gives an accurate reading and is often DRAMATICALLY lower
Just because it gives lower results doesn't mean it's more accurate. I can raise my arm during measurement or use a tourniquet above the cuff and get a lower result. That doesn't mean the measurement is accurate at all.
There are standardized procedures on how to measure BP. Your "accurate" method is not one of them.
The word "accurate" was the wrong choice of words. The machine itself is always going to be "accurate" if it's working correctly, and cuff is used right. Perhaps "proper" was a better word, since we're not talking about the accuracy of a measurement.
Since you'll get a higher readout after exercise, or even moderate daily activities, it's recommended that the person be perfectly relaxed for a few minutes before taking the reading. What I described is just my way of being perfectly relaxed, and what I know for a fact doctors do if they suspect an actual BP problem, and want to "scrutinize" it to find the true lowest resting reading.
I don't disagree, but wouldn't the counterargument be that the 120/80 and 140/90 thresholds (or whatever they've redefined hypertension as) apply precisely to sitting rather than lying, and after only a minute's stillness, rather than ten? And also that you spend 16 hours out of 24 not lying down?
You don’t live your day to day life listening to soft music, lying down ready to doze. If your BP is elevated due to stress throughout the day it’s elevated, you will accumulate the harms. Idealizing conditions also gives a misleading reading.
> Now if you want to see I'm right, get up and walk around some and then sit back down and take another reading.
This doesn’t prove you’re right, just demonstrates normal physiology. Kind of like saying when you dyno an engine you should do it at idle. That is a valid measurement, just not the one that’s interesting.
In a healthy adult you will see a more significant increase in systolic pressure, but mean pressure shouldn’t rise nearly as greatly.
What you’re trying to observe is not the minimum ideal (your method) nor the short term maximums but an average of normal activity.
There’s a reason why ambulatory BP monitoring is the gold standard for diagnosing hypertension.
If you go to an emergency room and say you've taken your BP and it's high, they'll do basically what I said. Lay you down, let you relax 10 min, and then take a reading. If the reading comes up 120/80 they'll say go home, you're fine, whatever you did to take the BP yourself was wrong. I've seen this happen to someone. That's how I know.
You are confusing the assessment of an acute condition with a chronic one.
There is a huge difference between assessing and treating an acute elevated BP and chronic hypertension. ERs don’t treat or admit to the hospital for chronic hypertension.
As I said, you can’t assess chronic hypertension by only evaluating in idealized circumstances, however this is a fine enough way for ruling out hypertensive emergency which is all an ER cares to do. And yes, you want to idealize conditions if you’re considering aggressive emergent treatment protocols that can have serious side effects.
Like I said, the best option for evaluating chronic hypertension is 24 hour ambulatory BP (which of course would include quite a bit of resting time) - usually 15 to 30 minute intervals. Why? I think the first two sentences of the prior comment are pretty intuitive.
And truth be told if the reading comes up 160/100 they’ll still send you home and tell you to follow-up with your PCP. There are of course other factors (like say having heart failure, symptoms other than headache), but usually it’s BP north of 180/120 where the ER starts getting concerned, and even then you will likely be released for outpatient follow-up +/- some oral medication.
In the public, hypertension is primarily a chronic condition and a slow killer. There are only a few circumstances where rapid control of blood pressure is not counterproductive since over time your body compensates while your organs (primarily kidneys, heart, and brain/eyes) slowly worsen in function.
No I'm not confusing anything with anything else. You've just gotten offended over something -- probably the word "wrong" in my original post, which made you then decide to take it over literally.
I think people will get 90% of the way to lowest BP reading simply by being still and silent for 10 mins. I doubt the lying down part is that important. I just originally didn't know that. I'd be doing something active (or just worked out), then decide to take BP and get a high reading. I think you probably assumed every word of my initial post was meant to be an absolute thing, rather than a general idea of the necessity to be relaxed not only during the reading but for several minutes before.
Anyone can look that up and find out I'm right.
> No I'm not confusing anything with anything else.
Yes you are, since you are the one that brought up an anecdote about an emergency visit, and I am explaining why that is not relevant.
> probably the word "wrong"
I wasn’t offended, those were your words, that I took at face value. People actually can’t read your mind, apparently you think you can read mine.
> I think people will get 90% of the way to lowest BP reading
And I’m explaining to you why just getting the “lowest” BP reading is not the overarching goal in evaluating chronic blood pressure.
> I think you probably assumed every word…
I wasn’t the only one that criticized your wording, perhaps that should be a sign to you rather than a prompt to assess my psyche.
> Anyone can look that up and find out I'm right.
On that note, is there anything specific I have said that is inaccurate? Look it up if you wish. If not, what is the purpose of your bickering?
Yeah, I'm not even reading your latest list of grievances and pedantic nit-picking. If you don't think people should be relaxed when taking a BP reading, I only have two words for you "Google it."
If you're actually interested in learning something new, here you go: https://my.clevelandclinic.org/health/diagnostics/16330-24-h...
You managed to spout enough crap about the history of Javascript that it summoned Brendan Eich himself, and you even then continued to double down. It really seems like you might get some benefit by taking a deep breath and not letting every correction or even just piece of added information enrage you. That may also likely help your blood pressure.
I was pretty sure there was a grievance under the surface. So now it comes out.
Did you enjoy your stroll thru the graveyard of past debate participants? lol.
No grievance. We've never interacted before (nice edit, btw). Yes, the outsized defensiveness did prompt to see what I was dealing with.
After rereading my initial reply I am still puzzled as to why pointing out that ambulatory measurements matter got you bent out of shape. I can concede that "Idealizing conditions also gives a misleading reading." could probably be better worded as "gives a misleading picture", but I don't think that warranted such defensiveness and hostility, you seem to have ignored the overall point made in that comment.
I think it's pretty easy to see, on this thread, which person got "bent out of shape"
I've heard that for some people it's exactly the opposite. Standard procedure, IIRC, is to have the arm resting in a position that puts the cuff right about even with your heart. But some people get really big jumps in BP when supine, and I've heard it suggested that doctors might want to start doing their BP tests in that position because those people may not get diagnosed correctly despite spending a third of every day with high blood pressure.
I think the main point is not necessarily the laying down part, but it's just that you need to be perfectly still for 10 min. Your BP will still be dropping more even after 5 min. This is just how to get the lowest resting reading. Of course others on this thread have balked about whether this lowest readout has value on it's own.
Measuring at a single point in time is so inaccurate due to things as simple as circadian variation of blood pressure (morning surge, night time dipping, etc). Not to mention acute stressors, arm positions etc. It's hard to put any weight on a single reading, and tbh doctors already know this.
After some hypertension issues last year I bought an inexpensive ambulatory monitor (Contec ABPM50) for experimenting. Turns out the biggest contributor was likely undiagnosed sleep apnea, infact research suggests up-to 50% of essential hypertension cases are probably apnea related [1].
Sleep apnea is ridiculously common and significant apnea in young/middle aged individuals (particularly women) is associated with an up-to 5x increase in all causes mortality [2].
If have poor sleep, mental health issues (PTSD/anxiety/depression) and borderline/hypertension you should absolutely order something like a WatchPAT test. The odds of it coming back positive are probably 80%+. The STOP-BANG questionnaire is also pretty good: https://www.mdcalc.com/calc/3992/stop-bang-score-obstructive...
1. Chaudhary SC, Gupta P, Sawlani KK, Gupta KK, Singh A, Usman K, et al. Obstructive sleep apnea in hypertension. Cureus [Internet]. 2023 Apr 27; Available from: https://doi.org/10.7759/cureus.38229
2. Lavie P, Lavie L, Herer P. All-cause mortality in males with sleep apnoea syndrome: declining mortality rates with age. European Respiratory Journal [Internet]. 2005 Feb 28;25(3):514–20. Available from: https://doi.org/10.1183/09031936.05.00051504
Maybe someone could take the time to explain how it actually works. Somehow I missed it in my engineering education.
You have a bladder that goes around someone's arm, and it is inflated. It slowly deflates, and somehow this tells you the pressure in the blood vessels inside the arm.
But that raises some questions:
1) Your arm isn't just blood vessel, most of it is bone and muscle. And fat.
2) How does the inflation help? What about the deflation?
3) What is on the other end of the device?
The cuff inflates to constrict the brachial artery until it is completely closed (i.e. the cuff detects no pulse, i.e. the external pressure from the cuff exceeds the maximum systolic blood pressure). Then it deflates until it detects a pulse as blood once again is able to force through the cuff's constriction (this threshold tells it the systolic blood pressure). It continues deflating until once again it detects no pulse (i.e. the minimum diastolic blood pressure exceeds the pressure exerted by the cuff).
I am a skeptic about the diagnostic criteria for hypertension, and especially about low targets for management. Cochrane did a meta review not long ago that made it sound like the signal was pretty weak below about 160/100 (as you might expect, if the measurement wasn't very accurate, which I don't think it is). I'm not saying it's not dangerous at much higher levels, but if you're freaking out at 140/90 because a chart says STAGE TWO, imo you can take a chill pill.
https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD...
(Disclaimer - I am not A doctor, and I am definitely not YOUR doctor, just an interested party who thinks the science smells funny.)
Not surprised to hear about Cochrane's results. The science does smell funny. I read a bunch of hypertension papers this last year (I have a home machine and wanted to know how to interpret the results). Beyond the fact that inter-reading repeatability is very poor and a lot of the explanations are very ad-hoc ("fear of doctors" etc), there are other issues.
First problem: natural variance across healthy people is huge. Doctors have a target they think everyone should hit but it's just a gross average, they don't seem to take into account the possibility of genetic variance at all.
Second related problem: it's common to be told what a healthy BP is for an "adult" although BP averages for men and women are quite different, and BP is also heavily affected by age (controlling for health).
Third problem: correlation is not causation. It's a cliché because it's a real issue. The public health community is prone to blurring the line between "two variables are found to be related in a study" and "one therefore causes the other" without doing the work to prove causality, and when I went looking for what studies established BP->cardiovascular disease causality it was remarkably hard to locate firm evidence. It could easily be the other way around. Indeed in most hydraulic systems it's understood that pressure is the result of other mechanisms and under/over pressure is the result of malfunction in pumps or piping. In healthcare they argue it's the reverse: that over/under pressure is the cause of malfunction elsewhere. There's probably a circular relationship but all the material targeted at regular people makes strong claims of causality when the underlying literature seems far less certain.
Fourth problem: perhaps unsurprisingly given the third problem I found studies where people were put on anti-hypertensives and there was no improvement. Actually I read one study where the treatment outcome was purely negative: there was no effect on heart disease or other outcomes of interest but there were lots of patients who fainted due to excessively low BP. This study seemed reasonable well constructed but the negative outcome didn't seem to reduce the field's certainty in anything (a super common problem in public health). Doing trials like this is hard because any time anti-hypertension drugs fail to work it's interpreted as evidence that the damage was already done earlier in life thus requiring ever longer studies to detect.
Fifth problem: a lot of the underlying scientific claims trace back to one longitudinal study in a single village in Japan, done decades ago. It's remarkable how often you follow citations and end up back at this dataset. When you look at what the study did it's kinda sketchy and not particularly convincing, but because the BP->CVD link is hypothesized to be a very slow acting effect it takes a huge effort to collect data. The field seems to be caught in a loop where they exaggerated their confidence early, so now there is not seen to be much point in doing better studies because it'd take years (bad for your career) and why study something that's already "known".
I’ve never seen a discussion how ‘reactive’ one is physiologically either when discussing BP. That is, is one the kind of person who is generally calm throughout the day, or is one who has larger swings based on various stimuli? I’ve had readings as high as 155/95 when stressed rushing to a doctor’s office visit and readings as low as 105/62 when calmer. I suspect blood pressures varies wildly through the day, and this variation depends on a person’s physiology.
>I’ve never seen a discussion how ‘reactive’ one is physiologically
Then you have never looked for it. This is pretty basic stuff taught in the very first year of the medical school.
>when stressed rushing to a doctor’s office visit
Even has a name: white coat hypertension.
>I suspect blood pressures varies wildly through the day, and this variation depends on a person’s physiology.
Yes it absolutely does. Just like your heart rate varies throughout the day, your BP keeps changing as well. That's why we like to measure it over 24 hours before any diagnosis.
Well then, instead of being smug, how about providing a reference? Specifically, can you link to information about the distribution of individual blood pressure daily variances across a population? This is different from white coat hypertension,something which nearly all of us are familiar.
To get you going here is a 2009 article on labile hypertension. It discuss the topic but does not provide any quantitative information on population distribution.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8673041/
Edit: here’s a link to a more recent reference:
https://www.imperial.ac.uk/news/251055/blood-pressure-variab...
Apparently, contrary to your assertion that an individual’s blood pressure variability is part of established 1st years med student’s knowledge, labile hypertension seems to be an active area of research.
I had a major heart scare when I was 39 so I’m quite obsessed with my blood pressure. This is anecdata based off of my own experience with my heart, brain and body.
(Note that this is based off of someone capable of developing a heart problem in his late thirties so hopefully none of this will apply.)
Before I started running for fun, running up to a doctor’s office would absolutely spike my blood pressure. That was a combination of anxiety (which is/was an issue), cardiovascular health and basic physical reactions to exertion. Since I started running for fun, that relationship has completely changed. I don’t get the anxiety based blood pressure changes because I find running really fun and rewarding.
When I lift weights, my blood pressure will read a little higher for at least 24 hours after. The heavier I lift, the more my blood pressure will lift. I see a similar relationship with volume, but it’s not as linear as weight. So if I have to do fifty total reps to failure my blood pressure will be higher, but not as high as if I had done ten total reps to failure.
Food and alcohol have tremendous impacts. Cannabis has an impact but nowhere near the impact of either food or alcohol. Armed only with blood pressure data, I could make a good case for fast food and beer to be illegal. My case wouldn’t be as strong for cannabis. Caffeine is really fucking weird - it increases blood pressure up to the point of addiction. Then, not feeding the addiction will spike my blood pressure even more.
And I haven’t even begun to talk about how heavily my brain is involved. I dealt with undiagnosed ADHD through developing some very obsessive habits. As a consequence, I can quite literally obsess my way back to blood pressure medication.
Judging by how much personal data I have on my blood pressure, I’m sure you’re very surprised that I tend to be obsessive. :)
So anecdotally, you are 100% correct. But I can add some more anecdotes to hopefully ease your mind. When I got out of the hospital, I had to promise my cardiologist three perfect readings a day; meaning that I would religiously check my blood pressure at the same three times each day. Needless to say, I checked it way more than that. But there is an awareness that different levels of need require different levels of scrutiny.
The only part I still wonder is if my cardiologist knew that giving an obsessive person metrics would lead me into running. This may have just been a way to get me back into shape.
One of my attendings has a running joke where he takes fresh interns in July and tells them "I will take you to <most expensive restaurant in my city> if you can take this patient's blood pressure correctly." He's been doing this for 30 years and no one has been treated to dinner yet. He's looking for the standard rest time, arm at heart level, everything.
After reading both the article and your comment I have to say I'm somewhat confused. I don't think I've ever had a medical professional not take all the right steps when taking a reading, is it common in some context?
I've never seen a physician take the 5 minutes of the patient resting with their arm at heart level, personally!
I've never seen a nurse not insist on the right position.
However I've always wondered how much of a difference my long torso makes when my blood pressure is measured. I'm 6'3", and it's mostly torso. The result is that a table that is the right height for most people, is low for me. And adjusting the table to match my body is something that I've seen a lot of variation on.
Seems it would be easy to equip exam rooms with a set of basic foam blocks that could help with patient positioning for this and other routine procedures.
Can any medical professionals chime in on how it's usually done for tall folks?
"Long torso body type" is, in general, an under-appreciated factor in ergonomics and product design, IMO.
A couple of off-the-cuff examples:
-The longer your torso, the worse a laptop computer affects your neck and posture. For long folks, upright posture requires keyboard and monitor to be vertically separated even more than most off-the-shelf monitor/desk/keyboard trays will allow. So a monitor hinged directly to a keyboard is the worst of all possible configurations.
-Most recent automotive seats seem to force the head forward, excessively curving the spine, and the longer the torso the worse the effect.
On the opposite side of the bell curve, a safe driving position is hard to achieve for drivers around 5ft tall and under. Correct/safe distance from airbags and pedals seems to be overlooked for those of shorter stature.
I wish solving problems experienced by body proportion outliers was a higher priority for product companies.
That isn't just recent automotive seats. I've been having that problem for decades. Particularly bad offenders are Budget rental trucks and airline seats.
But it is getting worse. The more ergonomic they try to make the seat, the worse it is to sit in. My usual reaction to renting a car is, "Well, there's another model that I'd never consider buying."
Add clothes to that list. It's such a pain in the butt to find shirts made for people who are long torso without ending up with a shirt that's larger in every other dimension too. Even ones specifically labeled 'tall'
You need to find brands that have a slim sizing variation, coupled with a tall sizing variation. Ex j crew pre private equity, had good slim tall offerings.
Why are recent auto head rests doing this? I hate it and I am nearly to the point of removing the head rest when I drive (but maybe that has downsides in an accident scenario).
Wish I knew! My tentative plan for my next vehicle is to fabricate a custom head rest/restraint.
> "If you are consistently measuring blood pressure with an unsupported arm, and that gives you an overestimated BP of 6.5 mmHg, that's a potential difference between a systolic BP of 123 and 130, or 133 and 140—which is considered stage 2 hypertension,"
Okay, but that's a small and borderline difference?
4~7 mmHg isn't going to make or break a hypertension diagnoses. 20~30 mmHg definitely.
This shouldn't be downvoted.
If you're +-7 in your reading, don't panic yet. If you're there with a stage 1 or 2 hypertension diagnosis (130-140+ systolic), the margin of error discussed in this article isn't necessarily meaningless, but remarkably close to it - you need to address an issue there.
More as a PSA for you hardworking programmers and IT managers out there: if you have chronic hypertension, address it sooner than later. If you think to yourself that you'll start jogging daily starting next week, and your doctor is giving you the option for meds, just get on the damn meds. If you start an exercise regimen that can quantifiably manage it without the meds later, great. Don't let the perfect be the enemy of the good. Hypertension is the silent killer, and before it kills it contributes to all sorts of other bad problems and conditions.
Hypertension can also make you feel like crap. It made my chest feel tight, which did not help my anxiety.
Yeah, I empathize. Glad you're doing better now, assuming you are. I would get awful headaches and nausea (like hide in a dark room, photophobic, overly sensitive to sound, smells, wishing I could chop my head off). For years I didn't connect the two. Felt like getting the worst two-day hangover without having drank anything, but if I had measured my blood pressure at the time it would have been well over 150. I clocked in at 170 during one of those episodes when I went to urgent care. For years I had just dismissed as having overdid it the prior week and just needed to rest. Even if you can put up with the pain like a badass, it's not healthy for your system to be redlining so often. It does its damage in the aggregate.
As a just-in-time bordering on chronically late individual (typical engineer), sprinting on foot or bicycle to the doctor’s office has led to some unusually high reading.
I always wonder to what extent coffee affects the readings as well (on top of rushing into the office, commonly up stairs).
Automated BP cuffs painfully over-inflate; my BP is 20+/15+ higher when they're used.
I ask nurses to take my BP manually.
Hmm, I find that the tighter the cuff goes, the lower my reading goes...
I had a similar issue, which was remedied by getting a larger cuff. In retrospect it makes sense that one size does not fit all, and apparently my biceps are on the larger side.
Cuff sizes are targeted to a range of arm sizes. The range should be stated either on the cuff or in the manual. Using improper sizes over/underestimates the pressure values.
Yes, and that's so obvious in hindsight, but the monitor I was given at the doctor's office came with a size that was too small for me. It's not something one thinks about until it becomes an issues.
I was also fed up with inaccurate readings, and was trying to prototype a medical device that would have an adjustable cuff based on arm size. I ran it by my concierge doc, but apparently the latest tech is to use light waves to measure BP, similar to how wearables are doing pulse OX and Heart Rate. The technique is known as Photoplethysmography (PPG).
There are devices that are sold with various swappable cuff sizes.
Putting aside the implementation technicalities, which I know nothing about, I'm convinced that markedly superior outcomes will be driven by something (e.g. watch-like devices) that captures entire weeks worth of regular BP readings across all times of day and night to provide a significant body of data.
I always figure it’s just a good method to track changes in trends - not so much is this reading accurate, but how does it compare to the last 20 you’ve taken - has your blood pressure been trending upwards? Might want to get that looked at.
Only time I ever recall a nurse that insisted on doing BP measurements wrong was .. in jail. And not like all the nurses there, just this one person who did not care about anything besides flirting with corrections officers and getting the hell out of there ASAP.
I can lower the results by 10-20 points just by breathing deeply during the reading.
Yes, everyone can do that to some extent.
Yeep, definitely can drop 10-12 for me as well
Found out I had been worried about my blood pressure for no reason for close to 4 years. When I moved I brought it up to my new doctor and he said "what color was the cuff". Turns out they were using one entirely too small for my arm, which wouldn't you know it gives false-high readings. Turns out my blood pressure is frickin perfect.
The study tested two incorrect positions and the correct position. It “confirmed” that the correct position is correct.
So it’s nothing new, and not anything that isn’t in practice and part of basic procedure
> And they underscore the importance of adhering to clinical guidelines calling for firm support on a desk or other surface when measuring blood pressure, the investigators add.
Aside from this, a lot of medical professionals, particularly the PA’s, seem to be very low knowledge on how to identify the veracity of blood pressure readings. I’ve multiple times had to ask them to retake the blood pressure when the reading was very high or low. It was really surprising the first time it happened and made me wonder what else is getting misreported
I'm always amazed at how many nurses take your BP with your legs hanging off of the side of a table, back unsupported.
every time I get my blood pressure measured, my arm hangs on some scaffolding thing the blood pressure cuff hangs from. not even an armrest. Height is also not really standard.
that said, arm was not in my lap, and not hanging freely at my side.
If it’s happening systematically to almost everyone than the whole system has been calibrated to that. Probably want measurements to be slightly high to err on the side of caution anyways.
>Commonly used arm positions can overestimate blood pressure readings
are these arm postitions used so commonly that what we call high or low blood pressure is based on them?
I have long arms which I think makes the difference more pronounced. I see a much larger difference than most people if my arm isn't supported at heart level.
In my experience in the US, nurses at primary care practices don’t really care and have no passion for their profession and the younger doctors are Anki flashcard veterans who could be replaced with a LLM and probably have the same outcome. Even DOs act like MDs these days- I guess it is easier to just write a prescription than advise traditional diets.
120/80 is an ideal blood pressure based on studies that show an association between elevated readings and an increased risk of heart attacks and strokes. More than half of humanity has a higher blood pressure than that. I believe most would have much lower readings if they stopped eating the trash food that capitalism has produced.
I jog, cycle, other light sports, work is walking a fair bit, and i eat well - zero trash, and even with meds I'm still way above 120/80. Heredity seems to play a part (my guess).
Wearing a waffle pattern shirt can also make the reading high. My blood pressure is 20 points higher if I wear a waffle pattern shirt than if I take it off.
That sounds like the guy who thought he had a leather allergy because whenever he woke up with his shoes still on he had a terrible headache and felt nauseous.
It only happens with waffle pattern shirts and changing shirts causes a consistent decrease in blood pressure measurements. My doctor pointed it out when I got a physical because he'd seen the same thing before with other people.
Pressure cuffs are sensitive to many factors outside blood pressure and are are pretty imprecise: news at eleven!
Real-life medical practice is basically going through the motions, then intuitively guessing the issue, prescribing something common since most cases are so banal and next patient please.
Engineer-minded people can discover lots and lots of such "obvious" issues in healthcare and of course the answer isn't that nobody would've guessed it, it just doesn't matter. Healthcare (outside of very specific diagnosable illnesses) is 90%+ medicine theater. People expect some pills, they want a few words with someone in a white coat, and their problem goes away usually by itself. Chronic persistent issues without obvious cause befuddle docs and they often don't find anything even after lots of tests.
Our better health and longevity today is more due to better work conditions, better food, better sanitation and food preservation, basic vaccines, basic disinfectants, basics like penicillin, smoking less etc. And the low hanging fruit to improve further is lifestyle: eating/drinking fewer calories (especially less sugary stuff), exercising/sleeping more and having better social connections. None of it is particularly arcane or in need of precise measurement.
> Engineer-minded people can discover lots and lots of such "obvious" issues in healthcare
It is a defining characteristic of "engineer-minded people" to think they understand better than others. Amusingly, they won't pretend to repair their car engine better than a mechanic, but they will strongly believe they understand all the bad tricks and failings of doctors. They almost never understand that current medicine is mostly experience and not hard science. Future medicine is science. 2024 medicine is not, and cannot be.
I wouldn't put the blame on them though. There's a lot of obfuscation and posing as science.
But at the moment it's intractable to do it at scale at a meticulous, evidence-based way. It's a bit of a Santa Claus moment to realize this. People want to believe someone has a proper grip on things. Medicine has done wonders in narrow, specific things like various surgeries - I'm mostly talking about everyday GP stuff where some average 65 year old has generic issues like blood pressure. It doesn't mean that nothing can be done, and I'll in fact say that a smart person with some biology/chemistry background and internet access can often figure out what they actually need,better than a median doctor with limited time and little deep thought effort to spend on the case.
Cultural change is very hard, especially since doctors enjoy a very high status which they earned through long years of very hard work. So the attitude similar to the opposition to Semmelweis persists.
What a world we live in. Dangerous times.
Honestly I'm not sure what a single point-in-time reading even accomplishes. I've been hooked up to a continuous blood pressure monitor a few times and it's always fun to see how low I can get it. It seems pretty useless without seeing where it fluctuates over time not in a doctor's office.
Aktiia makes a continuous optical blood pressure monitor that is available in the EU. It's like wearing a fitbit, but for bp. You calibrate it with a pressure cuff once a month.
I'm pretty sure they're going through fda approval in the USA now.
How do these work? You can't stay compressed all the time? Is it intravenal?
Once, when hospitalized, I had an arterial BP monitor that was continuous. The last systolic number I remember seeing before passing out from sepsis was in the 70s.
The ones I've been hooked up to just compress every few minutes so not terribly fancy.
Humm. Does it matter?
Just settle on a standard arm position for the measurement and set the standards for that position.
I mean, you could even set the standard to be measured at the neck while the patient is hanging upside down and still the average would be average and the outliers would be outliers.
Yet another medical topic being discussed on HN, with comments full of disinformation and skeptics that think they've noticed something new that doctors have missed. Remember people, don't take medical advice from HN.
Those topics are fascinating. They reflect how a pretty well-educated population subset thinks about healthcare. It's almost always entertaining!
Definitely increases my BP though. Imagine someone ignoring their own health problems because they believed what a HN commenter said.
Well, it's clearly an echo chamber. There's very little actual transmission of knowledge in those topics. It's almost always about confirming pre existing beliefs. I'm an MD too, but I've been raised by scientists. Scientists in my own family entertain the same beliefs exhibited by HNers, to surprising extremes such as dismissing the effect of even very well understood drugs.
Last year, my father stopped his blood pressure meds and was very surprised when I could guess he'd stopped just by looking at him, then proceeded to explain how the drugs acted, and got even more surprised when he got much better 15 min after taking them again. Since then, he totally forgot about this event and is in complete denial. You can't change beliefs by explanation. People have to get to their own conclusions, otherwise you're just fighting windmills all the time.
Nice to see a fellow MD (very possibly older and more experienced than me) on HN.
>he totally forgot about this event and is in complete denial.
I can never understand this, especially with well educated people like your father or mine. I can't get mine to agree to go see a doctor (other than me - he doesn't believe me when I tell him something about medicine) for anything, even when there are obvious problems with his health.
You should have seen the COVID period on HN. It was glorious!
TLDR: Rest arm on table while taking a reading. Don't let your arm hang, unsupported, or flop on your lap. (15th paragraph has the meat of the article).