A Randomized Trial of Intensive versus Standard Blood-Pressure Control
Comprehensive Overview
Published in the New England Journal of Medicine in 2015, this study, known as the SPRINT trial, asked whether pushing systolic blood pressure below the commonly recommended target of 140 mm Hg, down to less than 120 mm Hg, would further reduce heart disease and death among adults at high cardiovascular risk, a question that remained genuinely uncertain because prior trials had mostly tested treatment down to less conservative targets. Researchers randomly assigned 9,361 adults age 50 or older, all with a systolic blood pressure of 130 mm Hg or higher and elevated cardiovascular risk but without diabetes, to a systolic blood-pressure target of either less than 120 mm Hg, called intensive treatment, or less than 140 mm Hg, the standard target. Blood-pressure medications were adjusted monthly using a standardized protocol to reach and maintain each group's target. The primary outcome was a composite of heart attack, other acute coronary syndromes, stroke, heart failure, or death from cardiovascular causes. The topline result was that intensive blood-pressure control significantly lowered the rate of this composite outcome, and did so decisively enough that the trial was stopped early, after a median follow-up of 3.26 years, once the benefit became clear.
Outcomes and Implications
The most important finding was that the primary composite outcome occurred at a rate of 1.65% per year in the intensive-treatment group compared with 2.19% per year in the standard-treatment group, a 25% relative risk reduction, and that all-cause mortality was also significantly lower with intensive treatment, a 27% relative risk reduction. Death specifically from cardiovascular causes was 43% lower and heart failure occurred 38% less often in the intensive group, benefits that were consistent across nearly every prespecified subgroup, including participants 75 years of age or older. Over the trial's median follow-up of 3.26 years, only 61 patients needed to be treated intensively to prevent one primary outcome event, and only 90 to prevent one death, a strikingly favorable ratio for a preventive intervention. These gains came with real costs: serious adverse events including symptomatic low blood pressure, fainting, electrolyte abnormalities, and acute kidney injury or renal failure occurred significantly more often in the intensive-treatment group, though rates of injurious falls did not differ between groups. Achieving the lower target also required more effort, with intensive-treatment patients taking roughly one additional blood-pressure medication on average. The authors conclude that among adults at high cardiovascular risk but without diabetes, targeting a systolic blood pressure below 120 mm Hg, rather than below 140 mm Hg, significantly lowered rates of major cardiovascular events and death from any cause, though this benefit must be weighed against a higher rate of certain treatment-related adverse events.