Safety and Effectiveness of Dabigatran and Other Direct Oral Anticoagulants Compared With Warfarin in Patients With Atrial Fibrillation

The study objective was to evaluate the safety and effectiveness of dabigatran and other direct oral anticoagulants (DOACs) compared with warfarin among patients with nonvalvular atrial fibrillation using a prospective monitoring program. We implemented a cohort design with propensity score matching to compare initiators of DOACs and warfarin between 2010 and 2015 in two US healthcare databases. Proportional hazards regression was used to estimate hazard ratios (HRs) for stroke and major bleeding. The final analyses included 29,448 dabigatran, 35,520 rivaroxaban, and 19,588 apixaban initiators, matched to warfarin initiators. The pooled HR for stroke was 0.75 (95% confidence interval (CI) 0.58-0.98) for dabigatran, 0.77 (95% CI 0.61-0.98) for rivaroxaban, and 0.69 (95% CI 0.50-0.96) for apixaban, consistent with findings from randomized trials. For major hemorrhage, the HRs were 0.72 (95% CI 0.65-0.80), 1.02 (95% CI 0.94-1.12), and 0.56 (95% CI 0.49-0.64), respectively, showing a decreased risk of major bleeding for both dabigatran and apixaban, as compared with trial evidence.