Atrial Fibrillation and Risk of Injurious Falls Among Adults With Hypertension: A Secondary Analysis of SPRINT

Background: Atrial fibrillation (AF) may increase susceptibility to falls, but its association with injurious falls among adults with hypertension and whether intensive blood pressure (BP) lowering modifies this association are uncertain. Methods: We analyzed 8,807 SPRINT participants with a baseline electrocardiogram and postrandomization follow-up for injurious falls. AF was evaluated at baseline and as a time-updated exposure incorporating AF identified during follow-up. Cox models estimated hazard ratios (HRs) and 95% CIs for the first injurious fall and assessed effect modification by randomized BP treatment assignment. Results: Among 8,807 participants, 163 had baseline AF, 142 developed AF during follow-up, and 637 experienced an injurious fall. In fully adjusted analyses, baseline AF (HR, 1.79 [95% CI, 1.18-2.70]) and time-updated AF (HR, 1.89 [95% CI, 1.32-2.71]) were associated with higher fall risk. The association with time-updated AF was similar with standard and intensive BP treatment (HR, 1.91 [95% CI, 1.12-3.26] and 1.94 [95% CI, 1.18-3.19], respectively; P for interaction=0.964) and across prespecified subgroups. Results were robust in competing-risk and temporal-lag sensitivity analyses. Conclusions: Among adults with hypertension and elevated cardiovascular risk, AF was independently associated with higher injurious-fall risk. The association was observed with baseline and time-updated AF and was not modified by intensive BP lowering, suggesting that AF identifies patients at increased fall risk without evidence that intensive BP treatment amplifies this risk.