I track my blood pressure at home using a domestic monitor. From November 2020 until July 2022 I used an armband monitor since then I have been using a wrist monitor. Gave up on the arm band device because it produced more error readings than usable data. (Typically upto 12 error reports for a single clear reading.) Now I notice that the readings from the wrist device are significantly lower; anything up to 30mmHg. I try to take my readings at the same time of day and on the same arm but this difference, which could take me from hypertensive to normal, is intriguing.
Anyone know of peer reviewed studies in the STEM literature on the difference/reliability/etc of the two types of monitors and whether the choice of one or the other has implications for personal health and for quantified self data collection?
The position of the cuff on the body, which side of the body (Right or Left) and the position your body is (standing vs sitting vs lying) can influence your BP measurements significantly. The guidelines suggest that the upper arm is more accurate ( as it is at the level of the heart) in a seated or standing position, however, as always in literature, the results are debatable.
To detect whether your BP is truly affected, I would choose your position of choice. Wait a minute in that position - take your BP on your upper arm, and then repeat the process using the wrist.
Thanks @Darren_Bowles. I pretty much do all those things. The instructions for the wrist monitors is to position over the heart. I always sit still for at lesat 20 minutes before taking my readings.
Thanks also for the hints on the STEM papers. Only time I use Google is their Google Scholar searhes. (Normally only ever use DuckDuckGo.)
@Darren_Bowles now had an opportunity to read the results from those papers and well their conclusions are inconclusive. #2 and #3 disagree on the equivalence of upper-arm and wrist monitors!
Exactly and it’s not surprising given the range of variation of confounding variables like normal variations in arterial anatomy & peripheral vascular disease ( that’s why the 2ns study controlled for ABI index - which, on a higher level, is a tool that detects the severity/ presence of peripheral vascular disease).
What it does boil down to, when it comes to finding out the implications on your health, is finding what is the case with you, how standardised your method of taking BP is, and the devices your using.
When it comes to device, this is a decent study that looks at how accuracy is determined and can be improved with wrist devices ( although the cases are low ( n=20), likely because it involved a trip to the cath lab))
My friend recently got an Aktia that does continuous readings throughout the day and night. Helped him track and resolve high blood pressure trying out a lot of different things. In the end paced breathing made a big difference.
Expensive! Would rather buy a Withings cuff BP monitor for half the price.
I still hold out for BP minitoring on an Apple Watch. (There are other things I want from a wrist band than just BP monitoring and Apple Watch has 90% of those.)
I couldn’t find any published data on the accuracy of the YHE watch so I’d be hesitant to trust the results.
Personally I’ve been using the Aktiia band for the last couple of months and I’m quite happy with it. This study has more data on the accuracy of the measurements. I wanted to see trends of how my blood pressure changes when I travel, when I sleep, when I’m stressed, after a workout, etc. and this band is more than accurate enough for that.
It is the $199 price that I consider expensive especially with the Pound being weak at the moment. Think I’ll hold out for a BP feature on Apple Watch.
The last I researched, there was only one market-accessible method to measure blood pressure reliably: the tried/true displacement method using a cuff. There is the potential to measure blood pressure using radar technology, but the patent is held by someone/a company Blumio already working to make it a market-ready wearable. (Blumio was acquired by CardieX, its worth keeping an eye on this company as a QS nerd)
Recently a family member of mine was sold a ‘smart’ watch monitor (Fitnus - avoid them, their claim is that using math + Photoplethysmogram sensors is accurate) claimed it measured BP. We did a side-by-side multiple-measurement comparison between the watch readings and a BP cuff, and the watch was horrendously inaccurate.
If you’re trying to monitor BP for a preventive reason (like my loved one is after a stroke), I recommend you stick with measures using displacement instead.