Re:Doctors Have Been Measuring Blood Pressure All Wrong, Stu...
by atahanacar on Monday September 11, 2023 @09:02PM
(#37475748)
>I have to drop nearly dead and only then will I go to doctors' for diagnosis and treatment.
This is a healthcare issue specific to your country. It is not a problem of "not enough measurements".
Regarding using tech like smartwatches for blood pressure measurement, it is currently not possible. They aren't measuring your blood pressure, they are simply correlating optical data like pulse transit time with your blood pressure, which is mostly inaccurate. If you have to calibrate every now and then using actual bp measurements, then you already have enough data and don't need your smartwatch.
After being diagnosed with elevated BP, I googled and read what I could and concluded: 1) Cheap "BP monitors" on Amazon just show random readings or the same readings so they are worse than useless: someone may actually use them and believe their readings. 2) There are only few smart watches that have BP measuring function.
I am currently using Samsung Watch Active2, and it seems to do the job. There is calibration that is good for 30 days only. After 30 days it expires and I calibrate it again. Calibration involves making 3 measurements in parallel, watch on one hand and manual BP monitor on the other. After each measurement on the manual BP monitor, I tell the watch App what was measured.
After each calibration I do another 3 measurements in parallel, again using both the watch and the manual monitor. I compare the watch (post calibration) readings with the manual BP readings. Usually the difference is small within few percent. If it is more than 8-10% I redo the calibration. This has happened 2 times in the 25 odd calibrations I have done. Usually the reason is noise instead of perfect silence (person coming in the room and talking, TV being turned on).
I have tried using the watch on Person2 after being calibrated on Person1 - and Person2 got crazy BP readings. So the calibration really does something, it is not nothing.
The watch measurements also approximately agreed with measurements taken over 24h period when I wore BP holter (automated BP cuff that inflates every 30 mins and measures and records the BP).
Over time I have become more lazy with the re/calibration: now several days pass before I re/do it. So I'm acutely aware that any non-100% automated data collection will eventually be abandoned on long enough time horizon. Redoing the same is boring and becomes more so with time.