The new guidelines, from the American College of Physicians and the American Academy of Family Physicians and published in the Annals of Internal Medicine, are very similar to those that family physicians issued in 2014, calling for treatment of adults 60 and older when blood pressure is 150 or higher and aiming for less than 150, meaning a reading in the 140s is fine. (For people under 60, the goal was less than 140.) Those guidelines were controversial, and the new ones — coming in the wake of a high-profile 2015 study called SPRINT that argued for a lower target — are already, too.
“It seems like we’re back to 2014,” said Dr. Jackson Wright, director of the clinical hypertension program at University Hospitals in Cleveland and first author of the SPRINT study. “Even then, there was a lot of dissent and, since the SPRINT trial has come out since, I was surprised” by the new ACP/AAFP guidelines.
Even physicians who urged caution in adopting SPRINT’s aggressive, below-120 target in people at elevated risk of stroke and heart attack questioned the new, looser guidelines.
The “recommendations that clinicians initiate treatment in adults aged 60 or older with systolic blood pressure persistently at or above 150 are inappropriate,” said Dr. Franz Messerli, a cardiologist at the University of Bern in Switzerland. “Even less acceptable is a target … of less than 150 in this group. With such a elevated target there is substantial evidence of an increase in stroke risk.”
Last year, Messerli warned against embracing SPRINT’s aggressive blood pressure target, saying a goal of below 120 “clearly has to be considered absurd.” He believes that, for otherwise healthy patients, something in the 120s is OK.
The new ACP/AAFP guidelines are stricter for patients who have had a stroke or a transient ischemic event (known as a mini-stroke), or who have risk factors such as high cholesterol, obesity, diabetes, or atherosclerosis. In those cases, people should reduce their blood pressure below 140, the groups said. That, too, raised eyebrows. “Wouldn’t it perhaps be better [to get below 140] before such a devastating complication has taken place?” Messerli asked.
The medical groups defended their new guidelines, which are based on the SPRINT study and 20 other randomized controlled trials.
That research showed that “any additional benefit from aggressive blood pressure control” — meaning reducing blood pressure below 140 — “is small,” said ACP president Dr. Nitin Damle.
The more lenient targets also reflect the harms of aiming lower. As people take more kinds of anti-hypertension drugs (three is not unusual) and higher does of them in an effort to drive down their numbers, they are more likely to have side effects like coughing and low blood pressure, which causes lightheadedness or fainting.
As a whole, the analysis of the 21 studies found, most of the evidence for the benefits of treating high blood pressure came from studies of patients who started out above 160 and got into the 140s. Studies that aimed for less than 140 “showed no statistically significant reduction in all-cause mortality or cardiac events,” the authors wrote in the Annals paper, though they did find a reduced risk for stroke.
For instance, a 2012 Cochrane Review concluded that in otherwise healthy adults with blood pressure of 140 to 159, blood-pressure-lowering drugs “have not been shown to reduce mortality or morbidity [death or disease] in randomized clinical trials.”
The SPRINT trial offered the strongest counterargument to that, finding benefits in reducing blood pressure to 120 or less. But it studied only people at high risk for cardiovascular disease. And it has been criticized for measuring blood pressure differently from how doctors usually do it, with the result that a reading of, say, 120 in SPRINT would be 128 or so in ordinary practice.
What’s indisputable is that the clashing, changing guidelines confuse both laypeople and doctors. The American Heart Association, for instance, says that in adults systolic blood pressure of 140 or more means “poor” cardiovascular health, 120 to 139 means intermediate cardiovascular health, and below 120 is “ideal.”
“For the public as well as practitioners, what the competing blood pressure guidelines illustrate is that there are different ways to interpret the same research,” said Dr. Vikas Saini, president of the Lown Institute, which warns against medical overtreatment. “The interpretation of the same data can be as different as half empty and half full.”