SPRINT Trial Results Confirmed in New Analysis: Yes, Lower is Better

Grace Halsey

An analysis of final data from the landmark SPRINT trial has confirmed findings that support aggressive treatment of hypertension to reduce CV morbidity and mortality.

Final data from the landmark SPRINT trial on the effect of more aggressive blood pressure (BP) treatment targets for patients with hypertension support initial findings that achieving a systolic BP of <120 mm Hg significantly reduces the risk of heart disease and stroke and death from these causes as well as all-cause death.

Results of the most recent analysis of SPRINT data, published in the May 20, 2021 issue of the New England Journal of Medicine, indicate that a target SBP <120 mm Hg is associated with significant reductions in risk of myocardial infarction, acute coronary syndromes, and stroke, as well as cardiovascular and all-cause mortality when compared to the traditional standard treatment target of <140 mm Hg.

"One criticism of the original SPRINT findings was that, of the components of the primary outcome, only heart failure and death due to CVD were significantly lower in the intensively treated group," said Cora Lewis, MD, Professor and Chair of the Department of Epidemiology in the University of Alabama at Birmingham School of Public Health, in a statement. "The final results found that risk of heart attack, along with heart failure, and death from CVD, was significantly lower in the group treated to less than 120, and the risk of the primary outcome excluding heart failure was still significantly lower in the more intensively treated group."

The randomized controlled Systolic Blood Pressure Intervention Trial (SPRINT ) was sponsored by the National Heart, Lung, and Blood Institute, of the National Institutes of Health (NIH) and conducted between November 2010 and 2015.

Researchers enrolled 9,361 participants aged at least 50 years who had SBP 130-180 mm Hg and increased risk for cardiovascular disease but without a history of diabetes or stroke. Participants were randomly assigned in 1:1 fashion to achieve an intensive treatment target (SBP of <120 mm Hg) or a traditional target (<140 mm Hg). The study's Data Safety Monitoring Board stopped the trial early (2015) based on the benefit seen with intensive blood pressure lowering on the study's composite endpoint.

Treatment to SBP <120 mm Hg decreased the rate of a composite cardiovascular disease (CVD) outcome by 25% and the rate of all-cause death by 27% compared to treatment to the standard target of <140 mm Hg.

Data collection continued through the end of the intervention period in 2015 and and post-trial observational data were collected through July 29, 2016.

The current analysis, after a median follow up of of 3.3 years, found the intensive blood pressure goal was associated with a 27% reduction in risk of the primary composite outcome (1.77% vs 2.40%; [HR, 0.73; 95% CI, 0.63-0.86; P=.001)]) and a 25% reduction in risk of all-cause mortality (1.06% vs 1.41%; [HR, 0.75; 95% CI, 0.61-0.92; P=.006]), each similar to the earlier SPRINT findings.

Investigators pointed out no significant differences were observed in the composite renal outcome among those with chronic kidney disease at baseline. The rate of serious adverse events did not differ between treatment groups. However, the incidence of hypotension, electrolyte abnormalities, acute kidney injury or failure, and syncope was greater among those in the aggressive target group.

"We know a lot about how to prevent and treat hypertension and SPRINT continues to greatly expand this knowledge, including the benefits of treatment on the heart, kidney and brain," said David Goff, MD, PhD, director of the Division of Cardiovascular Sciences at NHLBI. "As we implement what we know, more research is still needed to develop more effective prevention strategies for hypertension, improve its monitoring and control, and reduce the large health disparities associated with this disorder. Research teams supported by the NIH are continuing to work on these challenges."