Association between single-pill combination therapy use and blood pressure control in the Systolic Blood Pressure Reduction Intervention Trial: a post hoc analysis

Blood pressure (BP) control remains suboptimal among US patients with hypertension. Single-pill combination (SPC) therapies are commonly used to improve adherence; however, their effectiveness for achieving early and sustained intensive BP control is unclear.

We performed a post hoc analysis of Systolic Blood Pressure Intervention Trial (SPRINT) including 2736 participants propensity matched in a 1:2 ratio to compare effects of SPCs with equivalent multi-pill therapy. The estimated marginal odds of achieving target BP control were derived using generalized linear mixed models with repeated measures (LMMRMs). The association between time-updated SPC use and BP change in short- (≤6 months) and long-term (>6 months) follow-up was assessed with LMMRM and SPC * time interaction term. Multivariable Cox models evaluated the association of SPC use with cardiovascular events and serious adverse events (SAEs). Among SPRINT participants (n = 8623), 9.3% (n = 803) were prescribed SPC at baseline with greater use in the intensive vs. usual care group (5.79 vs. 3.90 per 100 person-months; P-diff < 0.001). Among matched pairs [SPC (n = 912); multi-pill therapy (n = 1824)], SPC use was associated with 22% increased likelihood of achieving target BP by 6 months [odds ratio (95% confidence interval), 1.22 (1.05, 1.42)]. Participants receiving SPCs (vs. multi-pills) experienced more rapid BP reduction in the first 6 months (−2.0 vs. −1.2 mmHg monthly change; P-diff < 0.001). Over long-term follow-up, participants using SPCs achieved significantly lower SBP at each time point. The risk of the primary CV composite endpoint and SAEs were not significantly different between groups.

Single-pill combination use resulted in greater likelihood of achieving target BP control and more rapid, sustained BP reduction without an increase in SAEs.