The WHO as well as the British Hypertension Society both recommend that blood pressure is taken with the entire arm supported at heart level. This means that the arm needs to be stretched out and be supported on a pillow at mid-sternal level. I came across a study that offers crucial information and that I would like to share. In the U.S. the risk estimation for high blood pressure is mostly based on the Framingham study. I was always wondering about their exact method of BP measurement. After years of searching, I finally found it here:
Adiyaman, A., Verhoeff, R., Lenders, J. W. M., Deinum, J., & Thien, T. (2006). The position of the arm during blood pressure measurement in sitting position. Blood Pressure Monitoring, 11(6), 309–313. doi:10.1097/01.mbp.0000218007.57957.56
As cardiovascular risk calculations are based on the Framingham study, however, it is important to realize that during the BP measurement in the Framingham study, the arm was not supported at heart level. In the Framingham study, BP was measured as follows: ‘The blood pressures were taken with the patient in sitting position, the left arm resting on the examiner’s desk.’ On the same page the authors state that BP is measured once by a nurse and twice by a doctor (one at the beginning of the physical examination and a second at completion).
This is very interesting. Multiple readings are good as we have examined in my other article. However, the measurements were not taken at heart level. This is unfortunate. It basically means the BP guidelines are based on faulty measurements and are inaccurate and likely misleading. Let me explain. As we have seen in the analysis above, and the last article also explains it well, BP must be measured at the level of the heart in order to be comparable. The problem is as follows. A “desk” is usually about 75-80 cm high. That’s somewhat of a standard. However, a “person” and an “arm”, they don’t have a standard length or weight, obviously. Now, a very tall person usually also has longer arms. If he rests the arm on a standard desk, his arm is almost vertical. Compare that to a very short person. His arm, on the same desk, is now almost vertical, i.e. at heart level.
What does this mean? The way they measured BP in the Framingham study, the following scenario would happen. Say Joe is very tall and Mike is very short, both have a wonderful BP of 120/80, measured at heart level. Now in the study they are measured with arm ‘on the desk’. Now Joe’s reading is falsely high at 150/95, whereas short Mike’s is 125/85. All over sudden, Joe needs BP meds for his ‘high’ BP.
So what happened? It appears to me that whoever were in charge of the Framingham study either don’t know the basic laws of physics or wanted to manipulate the data-set intentionally. As a result, the BP statistics they gathered are fundamentally flawed. Because a person’s height, arm length and arm weight (and arm’s blood volume), varies considerably, the measured BP values cannot be compared in a meaningful way between people of different height, arm length, and arm weight. All variables that lead to variation need to be eliminated, and everyone involved in scientific studies is usually well aware of that need. If they had measured each person’s BP with the arm supported at heart level, then comparing their BP ranges would make sense. But comparing a very tall person’s BP with the arm almost vertical and almost unsupported, to a short person’s BP with the arm close to heart level and fully supported, is not going to lead to meaningful and accurate predictions of BP risk, especially when arm position changes BP values by a whopping 20-30%, depending on the person.
To put it simple English, based on the Framingham study, the taller your are, or the thicker and/or longer your arms are, the higher your BP reading, because they measured it wrong. They should have documented and standardized their BP measuring procedure properly. What they have achieved by measuring with the arm on a desk is that otherwise healthy people with normal BP are now being told they have high BP and need BP medication. Thus healthy people are being medicated unnecessarily. Not only does this bring money to big pharma, it also makes the BP medications look better than they are because the a large percentage of people treated had actually normal BP, not high BP.
It appears that unlike what we are being told over and over again, perhaps, not everything in medicine is backed by rock-solid science. We should empathize with those people who get furious when they hear “the science is clear”, because it basically hardly ever is. Also, let us not forget that science and medicine are greatly influenced by politics and commercial interests, as the ongoing Covid pandemic has clearly proven beyond any doubt.
Hence, while we all agree that BP should be kept low, the actual BP guidelines are likely flawed. Instead of stressing about it, I like to remind myself of a German proverb: “Wer misst, misst Mist”, meaning when you measure something, you measure garbage. My personal observation so far is that those who live a life that is relatively stress-free, not giving a **** about anything, usually outlive everyone else.
National Differences, The U.K
When we check the UK’s National Health Service website at https://www.nhs.uk/conditions/blood-pressure-test/, we see their instructions reflect what we have been examining in depth in this article, their instructions agree with the recommendations of the WHO and the BHS:
Section “How blood pressure is tested”, quote: “you hold out one of your arms so it’s at the same level as your heart, and the cuff is placed around it – your arm should be supported in this position“. Also their definition of high blood pressure is still 140/90, not 130/80 as in the U.S. So now if you combine two facts it gets interesting: they measure the BP with the arm supported at heart level, hence the values will be lower. They also have a higher limit of what constitutes high blood pressure, namely 140/90 instead of 130/80. Looks like in the U.S. they really really want your BP low, much lower than anywhere else, so low that basically almost everyone needs medication. I guess their mission is accomplished.