Influence of metabolic syndrome and race on the relationship between intensive blood pressure control and cardiovascular outcomes in the SPRINT cohort.

Abstract

To determine whether baseline metabolic syndrome (MetS) modifies the effect of intensive blood pressure control on cardiovascular (CV) outcomes, and whether the effects varied by race/ethnicity. We performed post hoc analyses among non-Hispanic black, non-hispanic white and Hispanic participants, with and without MetS, in the Systolic Blood Pressure Intervention Trial (SPRINT), who were randomized to a systolic blood pressure (SBP) target of <120 mm Hg (intensive group, N = 4544) or an SBP target of <140 mm Hg (standard group, N = 4553). The median follow-up was 3.26 years. The primary outcome was the composite of the first occurrence of myocardial infarction, stroke, heart failure, non-myocardial infarction acute coronary syndrome or CV death. Overall, 3521/9097 participants (38.7%) met the criteria for MetS at baseline. Baseline characteristics were similar in the two SBP target groups within each MetS subgroup, except body mass index was slightly higher in the standard arm of the MetS subgroup (33.3 ± 5.6 vs 33.0 ± 5.3 kg/m2 ; P < .01), but were similar across treatment arms in the non-MetS subgroup. The hazard ratio for the primary outcome was similarly reduced in participants with or without baseline MetS: 0.75 (95% confidence interval [CI] 0.57, 0.96) and 0.71 (95% CI 0.57, 0.87), respectively (adjusted P value for treatment by subgroup interaction = .98). Similarly, there was no evidence of treatment × MetS subgroup interaction for all-cause mortality (adjusted interaction P value = .98). The findings were also similar across race/ethnic subgroups. In this analysis the CV benefit of intensive SBP control did not differ among participants by baseline MetS status, regardless of race/ethnicity.