Post-hoc analysis links lower systolic BP to higher cardiovascular risk in AF and stable CAD

BACKGROUNDS: The AFIRE (Atrial Fibrillation and Ischemic Events with Rivaroxaban in Patients with Stable Coronary Artery Disease) trial demonstrated that rivaroxaban monotherapy was non-inferior in efficacy and superior in safety compared to rivaroxaban plus single antiplatelet therapy in patients with atrial fibrillation (AF) and stable coronary artery disease (CAD). This study examined whether systolic blood pressure (SBP) affects clinical outcomes and modifies the impact of antithrombotic therapy. METHODS: In this post hoc analysis, participants were stratified based on median SBP at baseline: >126 mmHg (High SBP group, n = 1042) and ≤126 mmHg (Low SBP group, n = 1093). The primary efficacy endpoint was a composite of cardiovascular events and all-cause death. The primary safety endpoint was major bleeding. RESULTS: The mean SBP was 139 mmHg and 114 mmHg in the High and Low SBP groups, respectively. In the propensity score-matched cohort (n = 1684), the Low SBP group had a significantly higher incidence of the primary efficacy endpoint (hazard ratio [HR], 1.38; 95% confidence interval [CI], 1.01-1.88; p = 0.039), while the primary safety endpoint was comparable between groups. In the Low SBP group, rivaroxaban monotherapy was associated with lower risks of both the primary efficacy (HR, 0.60; 95% CI, 0.41-0.86; p = 0.006) and safety endpoints (HR, 0.40; 95% CI, 0.22-0.74; p = 0.003) compared with combination therapy, whereas no significant differences were observed in the High SBP group. CONCLUSIONS: Lower SBP was associated with increased risk of cardiovascular events and all-cause death. Rivaroxaban monotherapy demonstrated more favorable efficacy and safety outcomes particularly patients with lower SBP.