Newest report (via slate) says a "cochrane" study of high blood pressure proves we don't have to treat mildly high blood pressure, and that there are no studies to say otherwise.
nonsense, of course.
The Cochrane study is a "metanalysis" that puts a bunch of different studies into the computer and figures out the average.
The problem: Different criteria, different populations, and some studies are nonsense. It's often Garbage in Garbage out.
I'm old enough to remember when we first got good blood pressure medicines, and debated whether we should treat those whose BP was "only" 150-160...the study that convinced us was one that took some veterans and treated them to keep their pressure under 140 and others they left untreated at 160. Short term, no problem. Long term: More heart attacks and strokes.
I explained to my patients that severe high blood pressure was like running your car at 80 mph in first gear: you will burn out your engine quickly. But mild to moderate high blood pressure was like running your care in second gear: your engine will work fine, but wear out faster than if you used 3 or 4th gear when you went fast.
Here is a VA study on BP in those with type 2 diabetes that shows you need to keep the BP low.
and here is a link to the European HOT trial (hyptertensive Optimal treatment)..that used the lower number:
The lowest incidence of major cardiovascular events occurred at a mean achieved diastolic blood pressure of 82.6 mm Hg; the lowest risk of cardiovascular mortality occurred at 86.5 mm Hg. Further reduction below these blood pressures was safe. In patients with diabetes mellitus there was a 51% reduction in major cardiovascular events in target group < or =80 mm Hg compared with target group < or =90 mm Hg (p for trend=0.005). Acetylsalicylic acid reduced major cardiovascular events by 15% (p=0.03) and all myocardial infarction by 36% ...Diabetics, of course, are at high risk. What about the healthy elderly, especially those whose blood vessels are less elastic so the top number of the BP go up? There too you get a lower mortality, although the actual numbers are low: Again, a European study:
Among elderly patients with isolated systolic hypertension, antihypertensive drug treatment starting with nitrendipine reduces the rate of cardiovascular complications. Treatment of 1000 patients for 5 years with this type of regimen may prevent 29 strokes or 53 major cardiovascular endpoints.The Framingham study also found an increase in mortality but noted using the 140 number ignores age and sex differences. So we should be using the lower number to decide if we treat people in the general population.
Except that studies on the elderly show that the higher number is associated with higher death and stroke rates.
And then some folks are at higher risk, probably for genetic problems. Blacks have more hypertension, as do East Asians. Is it the high salt diet? Maybe (we see a lot of high blood pressure in the Philippines, probably from the high salt diet, and we only saw high blood pressure in Zimbabwe in those who ate a "european" diet). But it is probably also partly due to genetic factors. (Do folks working in the tropics tend to process the salt in a different way? Then why is BP so high in Japan? probably diet and genes)...
And in Native Americans, most of the hypertension is due to the high rate of diabetes/metabolic syndrome. Which is why when we were asked if we wanted to join a study to compare ACE inhibitors with Calcium channel blockers, I said no: ACE and ARD medicines were shown to slow down kidney disease deterioration in our diabetics, so we weren't simply treating blood pressure....
Translation: there is a problem of measuring blood pressure: different arms need different sized cuffs, and then there is "white coat" high blood pressure, which means your pressure goes way up but only when you are stressed.
And you have to take age into consideration.
Finally, the real question is if it is worth treating someone for 30 years with medicine so they won't die at age 55 of a heart attack. the "general" population studies mixes low risk people of all ages with high risk (e.g. diabetic black patients) patients.
Sorry, but if I have a Native American with a 150/90 top number, I'll treat. The question is if I need to treat a young thin person with a 120/100 pressure.
Usually we docs do personalize the treatment: The problem is now we are going to have to follow check lists and flowcharts to justify treatment and get it paid for. Uh, fellows, that is called the "art" of medicine: taking lots of things into consideration when you judge.
And with a government flow chart, a huge government push to do the paper work correctly, and of course making office visits "efficient", it means that maybe we don't have time to do small talk with patients and figure out what is really wrong with them. (cocaine anyone?)