Experts are urging doctors to ease up on using medications to control blood pressure in older patients. Rather than aim for a target blood pressure of 140/90 mm Hg, the target will be relaxed slightly to 150/90 mm Hg, according to new guidelines issued Wednesday.
The authors of the new guidelines, published in the Journal of the American Medical Assn., emphasized that they were not changing the definition of high blood pressure. Rather, they are recognizing that data from randomized clinical trials do not show that using drugs to nudge down systolic blood pressure from 150 to 140 provides any health benefit.
Systolic pressure -- the top number in a blood pressure reading -- measures the pressure in the arteries when the heart muscle contracts. Diastolic pressure, the bottom number, measures the pressure in the arteries when the heart muscle is relaxed between heartbeats.
An estimated 67 million American adults suffer from high blood pressure, known formally as hypertension, according to the Centers for Disease Control and Prevention. That works out to nearly 1 in 3 adults, making it the most common condition treated by primary care physicians.
People with high blood pressure force their hearts to work too hard, putting them at risk for heart disease and stroke, the No. 1 and No. 3 causes of death in the U.S., the National Heart, Lung and Blood Institute says. The American Heart Assn. also warns that hypertension can lead to atherosclerosis, kidney damage, vision loss, erectile dysfunction, memory loss, peripheral artery disease and other ailments.
Adults past their 60th birthday should maintain their blood pressure at or below 150/90 mm/Hg, according to the new guidelines. If patients are above that target, they should get medication from their doctors, the guidelines state.
This is a strong recommendation supported by moderate- to high-quality evidence that shows that lowering blood pressure below 150/90 reduces a patient’s risk of stroke, heart failure and coronary heart disease, the expert panel reported. Other data also suggest that reducing systolic blood pressure below 140 doesn’t lead to additional improvements, though the evidence for this is weaker, they said.
If patients in this age group are already on medications that keep their systolic blood pressure below 140 – in line with current guidelines – and they are tolerating that treatment well, they can keep doing what they’re doing, the panel advised. There is no need to ease up on medications to let their blood pressure rise to 150.
Adults under the age of 60 should maintain their diastolic blood pressure below 90 mm Hg, using drugs if necessary, the guidelines state. High-quality evidence from clinical trials showed that when patients between the ages of 30 and 59 kept their blood pressure below this target, they were less likely to have strokes, heart failure and premature death from any cause, the expert panel found. However, when patients reduced their blood pressure even lower, to 85 or 80, there was no additional benefit.
For patients between the ages of 18 and 29, the recommendation to maintain diastolic blood pressure below 90 mm Hg is based on a consensus of expert opinion, according to the JAMA report.
The panel said it could not find convincing evidence from clinical trials to recommend a specific target for systolic blood pressure in people under age 60. So the experts opted to stick with the current standard of 140 mm Hg.
The panel was guided by expert opinion in recommending that adults of all ages with diabetes or chronic kidney disease whose blood pressure is above 140/90 mm Hg should use medication to get it below that target.
Finally, the guidelines include recommendations about which drugs patients should use to control their hypertension. African American patients should start with calcium channel blockers or a thiazide-type diuretic. Other patients should try either of these drugs or an angiotensin-converting enzyme inhibitor (better known as ACE inhibitors) or an angiotensin receptor blocker (better known as ARBs). Patients of all races with high blood pressure and chronic kidney disease should be treated with an ACE inhibitor or ARB, the guidelines state.
If doctors can’t get their patients’ blood pressure under control after one month, they should add a second drug to the regimen, the experts advise. The guidelines go into more detail on how to proceed in stubborn cases.
The Eighth Joint National Committee, the formal name of the panel that developed the new guidelines, included experts in hypertension, primary care, geriatrics, cardiology, nephrology, nursing, pharmacology and other fields. They based their advice on data from large randomized clinical trials – the type considered the gold standard or medical research because they are least subject to bias. All of the studies had at least 100 patients and followed them for at least one year. The preliminary guidelines were vetted by 16 outside experts and representatives of five federal agencies. The feedback they offered was incorporated into the final guidelines.
Despite their detailed review of drug therapies, the experts said that medications aren’t the only way to control high blood pressure.
“For all persons with hypertension, the potential benefits of a healthy diet, weight control, and regular exercise cannot be overemphasized,” the panel wrote. “These lifestyle treatments have the potential to improve BP control and even reduce medication needs.”