High Blood Pressure
Growing Body of Evidence for Benefits of Lower Blood Pressure Targets
The table below shows the blood pressure categorization thresholds based on the 2017 consortium guidelines.8
We at Life Extension agree that “normal” blood pressure levels are below 120/80—with an optimal target being 115/75 for most adults up to age 80. According to the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, cardiovascular disease risk doubles for each increment of 20 mm Hg systolic and 10 mm Hg diastolic above 115/75 mm Hg.3 These findings become even more concerning when considering the staggering prevalence of higher-than-normal blood pressure: up to half of adults worldwide have blood pressure levels ranging from 120/80 to 139/89 mm Hg.9
A recent meta-analysis of observational studies showed that blood pressure in this range correlates with a nearly 20% increased risk of declining kidney function; the association was especially strong in older individuals.10
In 2006, an analysis of 8,960 middle-aged adults in the Atherosclerosis Risk in Communities (ARIC) study demonstrated that individuals with blood pressure levels ranging from 120/80 to 139/89 mm Hg had about double the risk of cardiovascular disease compared with people whose blood pressure was below 120/80 mm Hg.1
A meta-analysis of 61 prospective trials evaluated the relationship between blood pressure and cardiovascular-related mortality rates for one million individuals with no known history of cardiovascular disease. Researchers noted that at least down to 115/75 mm Hg, there is no threshold where lower blood pressure is not directly associated with lower mortality rates due to cardiovascular events. In addition, among people 40 to 69 years old, each 20 mm Hg difference in systolic blood pressure was associated with at least a twofold difference in overall mortality due to stroke, ischemic heart disease, or other cardiovascular events.2
With the publication of the SPRINT trial results, the evidence base supporting more aggressive blood pressure treatment targets in select populations continues to broaden. In late 2016, Life Extension Magazine published a comprehensive analysis of the SPRINT trial and an overview of the shortcomings of conventional views regarding blood pressure in an article titled “Lower Blood Pressure Empowers Longer Life.”
IS LOWER BLOOD PRESSURE ALWAYS BETTER?
The concept that “lower is always better” in the context of aggressive blood pressure reduction can be a recipe for disaster, in particular for elderly, frail patients.
Often told is the story of the young intern fresh from medical school graduation starting their residency. The intern aggressively treats their older patients to achieve rapid blood pressure reduction, yet is dismayed when their kidney function and cognitive abilities deteriorate rapidly.
Wiser, more experienced physicians know that older patients with pronounced pre-existing vascular disease and other medical problems often require higher blood pressure to perfuse critical organs like the heart, kidneys, and brain. These patients require a higher perfusion pressure to allow blood to reach critical organs and tissues throughout the body.11
Some older patients simply do not tolerate aggressive blood pressure reduction to a predefined value, which requires careful monitoring of kidney function and blood tests for BUN (blood urea nitrogen), creatinine, cystatin-C, and electrolytes like potassium and sodium, as well as assessment of cognitive function. These tests are necessary to facilitate appropriate titration of antihypertensive medication to a blood pressure tolerated by these patients.