According to officials at the National Institutes of Health (NIH), the Systolic Blood Pressure Intervention Trial (SPRINT) was stopped early due to a stunning improvement in cardiovascular outcomes in the group treated to a target systolic blood pressure (BP) of 120 mm Hg as compared to the “standard of care” control group treated to <140 mm Hg. The study (n=9300) began enrollment in late 2009 and included hypertensive subjects of diverse gender and ethnicity, who were at least 50 years old (25% were over age 75) and had one additional cardiovascular risk factor or preexisting kidney disease. Diabetes, stroke history, and polycystic kidney disease were exclusionary. The Data Safety and Monitoring Board (DSMB) stopped the trial early (slated to stop in 2016) upon finding that the subjects treated to a systolic BP target of 120 mm Hg showed a 30% reduction in cardiovascular events (e.g., heart attack, heart failure, and stroke) and nearly a 25% reduction in all-cause mortality vs. subjects treated to a systolic BP of 140 mm Hg. According to the director of the National, Heart, Lung, and Blood Institute (NHLBI) Gary H. Gibbons, MD., “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.
These trial results will no doubt bring hypertension experts back to the table to address systolic BP targets (which have been controversial in recent years) for US national guidelines. Note: the trial is continuing so that subgroup analyses can be completed that relate to the effects of the lower systolic BP target of 120 mm Hg on cognitive function, cerebral small-vessel disease (via MRI assessment), and dementia.