NIH: Lives Saved With Lower Systolic Blood Pressure

Abstract

Deaths were reduced by nearly one-quarter when systolic blood pressure was treated to a target of 120 rather than 140 mm Hg, according to a large National Institutes of Health–sponsored study comparing standard blood pressure treatment with more-intensive lowering of systolic blood pressure. The lower blood pressure group also saw a 30% reduction in the primary composite endpoint of cardiovascular events, stroke, and cardiovascular death. The magnitude of the effect of the lower blood pressure target prompted the study's data safety monitoring board to end the study early, said officials from several NIH agencies at a telebriefing. The study was unblinded in August, and a full report of the primary outcome measures will come in a paper due out by the end of the year, they said. The Systolic Blood Pressure Inter-vention Trial, or SPRINT, is a 100-site trial that enrolled more than 9,300 people in the United States and Puerto Rico at least 50 years old who had high blood pressure and who were at risk for cardiovascular disease; those with diabetes were excluded. Patients were randomized to a standard treatment target of 140 mm Hg or less or to a more intensive 120 mm Hg. SPRINT participants received evidence-based treatment with a variety of antihypertensives, with the intervention arm requiring an average of almost three medications, compared with just under two for the less-intensive treatment arm. Against a backdrop of uncertainty in the literature about what the target systolic blood pressure should be for those with hypertension and at risk for cardiovascular events or kidney disease, the study provides compelling evidence that more aggressive blood pressure lowering is important. “More-intensive management of blood pressure can save lives,” said Gary Gibbons, MD, director of the National Heart, Lung, and Blood Institute (NHLBI). Jackson T. Wright Jr., MD, PhD, SPRINT study lead and director of the clinical hypertension program at Case Western Reserve University in Cleveland, also emphasized that intensive blood pressure management can prevent the cardiovascular complications of hypertension. Although subgroup analysis is ongoing, the effect seems robust and consistent across age groups, sex, and ethnicity, he said. SPRINT, he said, also “offers an excellent opportunity to examine the tolerability and safety of the lower target.” The first look at the safety data shows that the more-intensive treatment is well tolerated, although data analysis is ongoing, he said. “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,” Lawrence Fine, MD, chief, Clinical Applications and Prevention Branch at NHLBI, stated in a press release. The previous absence of compelling data played a part in the debate surrounding blood pressure levels that should be used in guidance documents, and Dr. Gibbons and Dr. Wright both emphasized that they would expect the forthcoming primary outcomes paper to have an impact on guideline-writing bodies in the future. Dr. Wright said, however, “We are not providing guidance for providers or patients right now.” In 2014, the group of experts who had constituted the Joint National Commission 8 panel, a team assembled in 2008 by the NHLBI to update official U.S. hypertension management guidelines, set the target blood pressure for the general population 60 years or older to less than 150/90 mm Hg, a major break from long-standing practice to treat such patients to a target systolic pressure of less than 140 mm Hg (JAMA 2014;311:507–20). These guidelines, released after SPRINT began, remain controversial. The SPRINT study is also examining kidney disease, cognitive function, and dementia among the patients; however, those results are still under analysis and will become available as more information is collected over the next year. Kari Oakes is with the Midwest bureau of Frontline Medical News.