Systolic BP lowering to less than 120 mm Hg aggressively reduces mortality: NEJM
USA: Lowering of systolic blood pressure (SBP) to less than 120 mm Hg reduces the rate of MACE and all-cause mortality compared to lowering SBP to less than 140 mm Hg in patients at increased CV risk, according to final results from landmark SPRINT study.
SPRINT was a randomized controlled clinical trial sponsored by the National Heart, Lung, and Blood Institute, part of the National Institutes of Health. The trial that began in late 2009 enrolled more than 9,000 participants at least 50 years old who had SBP 130 to 180 and had increased cardiovascular disease risk.
The NIH ceased randomly assigned treatments in 2015, when data was presented to the Data and Safety Monitoring Board showing treatment to SBP of less than 120 decreased the rate of a composite cardiovascular disease (CVD) outcome by 25 percent and the rate of all-cause death by 27 percent.
Researchers reported these findings in 2015, but continued to collect data into July 2016. The current paper confirms and enhances the earlier findings.
Jackson T Wright, University Hospitals Cleveland Medical Center, and colleagues presented new evidence of the effectiveness of reducing SBP to a target range of less than 120 mm Hg.
"This final report of the findings from SPRINT, now including all cardiovascular and mortality trial events, confirms the benefit of more aggressive BP lowering compared the previously recommended target of less than 140/90 mmHg," said Dr. Wright, Director of the Clinical Hypertension Program at UH and Professor Emeritus of Medicine at CWRU.
The study included 9361 participants who were at increased risk for cardiovascular disease but did not have diabetes or previous stroke. They were randomly assigned to an intensive treatment target (systolic blood pressure, <120 mm Hg) or a standard treatment target (systolic blood pressure, <140 mm Hg).
The primary outcome was a composite of myocardial infarction, other acute coronary syndromes, stroke, acute decompensated heart failure, or death from cardiovascular causes. Additional primary outcome events occurring through the end of the intervention period (August 20, 2015) were adjudicated after data lock for the primary analysis. The researchers also analyzed post-trial observational follow-up data through July 29, 2016.
Key findings of the study include:
- At a median of 3.33 years of follow-up, the rate of the primary outcome and all-cause mortality during the trial were significantly lower in the intensive-treatment group than in the standard-treatment group (rate of the primary outcome, 1.77% per year vs. 2.40% per year; hazard ratio, 0.73; all-cause mortality, 1.06% per year vs. 1.41% per year; hazard ratio, 0.75).
- Serious adverse events of hypotension, electrolyte abnormalities, acute kidney injury or failure, and syncope were significantly more frequent in the intensive-treatment group.
- When trial and post-trial follow-up data were combined (3.88 years in total), similar patterns were found for treatment benefit and adverse events; however, rates of heart failure no longer differed between the groups.
"Among patients who were at increased cardiovascular risk, targeting a systolic blood pressure of less than 120 mm Hg resulted in lower rates of major adverse cardiovascular events and lower all-cause mortality than targeting a systolic blood pressure of less than 140 mm Hg, both during receipt of the randomly assigned therapy and after the trial," wrote the authors. "Rates of some adverse events were higher in the intensive-treatment group."
Reference:
The study titled, "Final Report of a Trial of Intensive versus Standard Blood-Pressure Control," is published in the New England Journal of Medicine.
DOI: https://www.nejm.org/doi/full/10.1056/NEJMoa1901281
