For people with diabetes of all types, blood pressure is one of the most important health markers. It can be taken quickly and easily, and offers a quick glimpse at cardiovascular health.
If a person has been physically active, eating sensibly, and managing his or her disease well, chances are good that blood pressure will be lower. If someone has been struggling to meet those goals, it most likely will be higher. And the connection between high blood pressure and serious health issues can’t be understated.
For all of these reasons, the issue of new blood pressure guidelines is important. Last month, the Eighth Joint National Committee (JNC 8) published its latest take on the evidence in the Journal of the American Medical Association. The recommendations gained a lot of attention for a few days in the national media, and then faded from view in the bustle of the holiday season. But the discussion has continued among medical professionals, and it’s important to recognize what the committee, looking at wide variety of evidence, concluded.
Most importantly, the paper set new guidelines for people over the age of 60. In these folks, medication to reduce blood pressure is suggested when systolic levels (the “top number” of a blood pressure reading) go over 150 or when diastolic levels (the “bottom number” of the reading) go over 90. Put simply, this means that many older people who were put on medications in the past might not be started on them today.
For those under the age of 60, the cut-off point is 140 systolic and 90 diastolic. But the systolic level isn’t necessarily supported by lots of evidence, according to the panel. It’s simply a continuation of previous guidelines. (The 90 cut off for diastolic pressure has some solid scientific support.)
For people with diabetes and those with kidney disease, the report includes a startling shift. The cutoff for blood pressure is now exactly the same as folks under 60–140/90. Many doctors have used a systolic pressure of 130 as the cutoff point for these populations. Why the change? The committee decided that there simply wasn’t compelling evidence that treating blood pressure in that range made a significant difference in health outcomes.
More broadly, the guidelines also raise the question as to whether treating moderate hypertension–that is, high blood pressure near these cut-off points–actually makes people healthier or prevents significant disease. What’s more, lowering blood pressure significantly can require multiple medications, which can be an issue in of itself for elderly patients who may be taking many other medications or suffering from cognitive difficulties.
“This is a large paradigm change,” wrote cardiologist Harlan Krumholz in The New York Times‘ Well blog. “The authors state that they did not intend to redefine what constitutes high blood pressure, but in effect they have now set it at 150/90 for the purpose of drug treatment of the general population. They have illuminated the weakness of our current body of evidence and made sensible recommendations given what we know.”
It’s a given that treating extremely high blood pressure saves lives and prevents strokes and other adverse health events. There’s not in question. But for people in these middle groups, the picture is murkier. Drugs do bring down their blood pressure, but the overall benefits are less clear. What is known–and what the committee noted in its report–is that lifestyle changes are perhaps the most important frontline treatment for those in this intermediate group. Losing weight, exercising, eating better–all of these things make people healthier overall and also reduce blood pressure.
It goes without saying that these guidelines have generated controversy in the medical community. When putting together these kinds of broad guidelines, it’s inevitable that some people’s beliefs and concerns won’t be addressed.
Some doctors, for instance, don’t want patients taking away the message that high blood pressure is somehow okay. As stated above, the correlation between high blood pressure and real, serious, pressing health problems is incredibly clear. Muddying the message, to these physicians, causes more problems than it solves.
The members of the committee who voted against the new guidelines wrote a piece outlining their concerns, which was published in the Annals of Internal Medicine. “We, the panel minority, believed that evidence was insufficient to increase the (systolic blood pressure) goal from its current level of less than 140 mm Hg because of concern that increasing the goal may cause harm by increasing the risk for CVD (cardiovascular disease) and partially undoing the remarkable progress in reducing cardiovascular mortality in Americans older than 60 years,” they wrote in the piece.
Make no mistake, if you’re already taking blood pressure medications, these guidelines shouldn’t stop you. If they raise concerns, they can instead be used as a starting point for discussion with your doctor or other healthcare providers. We’re all individuals, after all, and our specific needs vary.
But perhaps the most important effect of these guidelines is philosophical. For all that we know about health, for all of the drugs and treatments we have, there is still much that we don’t understand or that hasn’t been proven. (In the field of diabetes, for instance, there wasn’t a definitive trial showing that tight blood sugar control could prevent or delay complications until 1993–although some doctors were advocating the treatment many years earlier.)
We should be mindful, therefore, of all that we don’t know. And we shouldn’t expect medication to solve all of our problems. Instead, we should always remember the power that we have in our daily lives, in the simple choices that we make about what to eat and how to move, to affect our bodies and our health in profound ways.
The committee issued more recommendations than those covered here, principally in the area of medication. To learn more about what it said, and how doctors are interpreting the information, please explore the links below. The first goes to the committee’s report, and the following are analysis, summary and reactions.