How low should you go? Reducing systolic blood pressure target may improve outcomes

Reducing systolic blood pressure below the currently recommended level significantly decreases the risk of MI, heart failure, stroke and death in adults who are 50 and older and have high blood pressure, according to preliminary results of a study.

The National Institutes of Health (NIH), which sponsored the trial, announced the findings on Sept. 11. The NIH is expected to release the final results within a few months.

When the NIH announced SPRINT (Systolic Blood Pressure Intervention Trial) in 2009, it said the trial would last nine years. However, the preliminary findings caused the NIH to stop the blood pressure intervention earlier than it had planned.

Patients who were randomized to have a target systolic blood pressure of 120 mm Hg had a nearly one-third reduction in MI, heart failure and stroke and a nearly 25 percent decrease in the risk of death compared to a group that had a target of 140 mm Hg.

Current guidelines recommend a systolic blood pressure of less than 140 mm Hg for healthy adults and 130 mm Hg for adults with kidney disease or diabetes.

“Our results provide important evidence that treating blood pressure to a lower goal in older or high-risk patients can be beneficial and yield better health results overall,” said Lawrence Fine, MD, chief of the clinical applications and prevention branch at the National Heart, Lung, and Blood Institute (NHLBI), said in a news release. “But patients should talk to their doctor to determine whether this lower goal is best for their individual care.”

Between Nov. 8, 2010, and March 15, 2013, the researchers enrolled 9,361 patients at 102 clinics in the U.S. and Puerto Rico who were at least 50 years old and had a systolic blood pressure of at least 130 mm Hg. Patients also had to have evidence of cardiovascular disease, chronic kidney disease or a 10-year Framingham cardiovascular disease risk score of 15 percent or higher.

Patients were randomized to have the standard systolic blood pressure target of less than 140 mm Hg or an aggressive target of less than 120 mm Hg. The primary outcome was the first the occurrence of MI, acute coronary syndrome, stroke, heart failure or cardiovascular disease death.

Patients with diabetes, prior stroke or polycystic kidney disease were excluded. However, the study was diverse and included 3,331 women, 2,648 people with chronic kidney disease, 1,877 people with a history of cardiovascular disease, 3,962 minorities, and 2,636 people who were at least 75 years old.

“This study provides potentially lifesaving information that will be useful to health care providers as they consider the best treatment options for some of their patients, particularly those over the age of 50,” Gary H. Gibbons, MD, director of the NHLBI, said in a news release. “We are delighted to have achieved this important milestone in the study in advance of the expected closure date for the SPRINT trial and look forward to quickly communicating the results to help inform patient care and the future development of evidence-based clinical guidelines.”