Bleeding in patients with atrial fibrillation treated with dabigatran, rivaroxaban or warfarin: A retrospective population-based cohort study.

BACKGOUND: Randomized controlled trials (RCTs) have shown that dabigatran, rivaroxaban and warfarin cause similar bleeding rates.

METHODS: We performed a retrospective population-based cohort study to determine the incidence of bleeding in patients with atrial fibrillation (AF) beginning dabigatran, rivaroxaban or warfarin. Consecutive patients initiating anticoagulation for AF during a 3year period were identified using a computerized database. Patients who bled and required hospitalization underwent chart review. Bleeding incidences were calculated per 100 patient-years of treatment.

RESULTS: 18,249 patients were included: 9564 (52.4%) received warfarin, 5976 (32.7%) dabigatran, and 2709 (14.8%) rivaroxaban. Bleeding incidences were 3.9 (95% CI, 3.6-4.4) in warfarin-treated patients, 4.2 (95% CI, 3.7-4.7) in dabigatran patients, and 4.1 (95% CI, 3.0-5.3) in rivaroxaban patients. Intracranial hemorrhage (ICH) rates were 0.71 (95% CI, 0.56-0.90) for warfarin, 0.4 (95% CI, 0.18-0.87) for dabigatran, and 0.27 (95%CI, 0.10-0.80) for rivaroxaban. GI hemorrhage rates were 1.88 (95%CI, 1.62-2.20) for warfarin, 2.98 (95% CI, 2.4-3.5) for dabigatran and 2.39 (95%CI, 1.6-3.5) for rivaroxaban.

CONCLUSIONS: We demonstrate similar bleeding rates with both dabigatran 150mg and 110mg and rivaroxaban compared to warfarin.