Clinical Outcomes by Race and Ethnicity in the Systolic Blood Pressure Intervention Trial (SPRINT): A Randomized Clinical Trial

Abstract

Background: The Systolic Blood Pressure Intervention Trial (SPRINT) showed that targeting a systolic blood pressure (SBP) of ≤ 120 mm Hg (intensive treatment) reduced cardiovascular disease (CVD) events compared to SBP of ≤ 140 mm Hg (standard treatment); however, it is unclear if this effect is similar in all racial/ethnic groups.

Methods: We analyzed SPRINT data within non-Hispanic White (NHW), non-Hispanic Black (NHB), and Hispanic subgroups to address this question. High-risk nondiabetic hypertensive patients (N = 9,361; 30% NHB; 11% Hispanic) 50 years and older were randomly assigned to intensive or standard treatment. Primary outcome was a composite of the first occurrence of a myocardial infarction, acute coronary syndrome, stroke, decompensated heart failure, or CVD death.

Results: Average postbaseline SBP was similar among NHW, NHB, and Hispanics in both treatment arms. Hazard ratios (HRs) (95% confidence interval) (intensive vs. standard treatment groups) for primary outcome were 0.70 (0.57-0.86), 0.71 (0.51-0.98), 0.62 (0.33-1.15) (interaction P value = 0.85) in NHW, NHB, and Hispanics. CVD mortality HRs were 0.49 (0.29-0.81), 0.77 (0.37-1.57), and 0.17 (0.01-1.08). All-cause mortality HRs were 0.61 (0.47-0.80), 0.92 (0.63-1.35), and 1.58 (0.73-3.62), respectively. A test for differences among racial/ethnic groups in the effect of treatment assignment on all-cause mortality was not significant (Hommel-adjusted P value = 0.062) after adjustment for multiple comparisons.

Conclusion: Targeting a SBP goal of ≤ 120 mm Hg compared to ≤ 140 mm Hg led to similar SBP control and was associated with similar benefits and risks among all racial ethnic groups, though NHBs required an average of ~0.3 more medications.

Clinical trials registration: Trial Number NCT01206062, ClinicalTrials.gov Identifier at https://clinicaltrials.gov/ct2/show/NCT01206062.

Keywords: African Americans; Hispanics; blood pressure; clinical outcomes; clinical trials; hypertension; race and ethnicity.

Figure 1.

Consort diagram. Race/ethnicity was self-reported and participants were classified as: Hispanic regardless of self-identified race; non-Hispanic Black if self-identified as African American alone; and non-Hispanic White if self-identified as White alone.

Figure 2.

Follow-up SBP and mean number of antihypertensive meds by treatment arm and race/ethnicity. The SBP separation between treatment groups at year 12, 24, and 36 months was 14.4, 15.6, and 16.7 mm Hg, respectively in NHBs; 14.8, 15.5, and 15.0.