Direct Comparison of Low-Dose Dabigatran and Rivaroxaban for Effectiveness and Safety in Patients with Non-Valvular Atrial Fibrillation.

Abstract

We aimed to examine the comparative effectiveness and safety between low-dose dabigatran and rivaroxaban in atrial fibrillation (AF) patients. Using the National Health Insurance claims database in Taiwan, we conducted head-to-head comparisons among adult non-valvular AF patients prescribed with dabigatran 110 mg or rivaroxaban 15 mg between June 1, 2012 and May 31, 2015. A propensity score was derived using logistic regression to model the probability of receiving different non-VKA oral anticoagulants (NOACs) as a function of potential confounders, and an inverse-probability- of-treatment-weighted (IPTW) pseudo-cohort was created. A Cox proportional hazards model was used to compare clinical outcomes in the IPTW pseudo-cohort as the primary analysis. The propensity score-matched analysis was applied as the secondary analysis. Overall, 13505 dabigatran 110 mg users and 6551 rivaroxaban 15 mgusers were identified. In the primary analysis, the rivaroxaban 15 mg users had a higher risk of all-cause death [hazard ratio (HR) 1.19, 95% confidence interval (CI) 1.02-1.38]. In addition, the rivaroxaban 15 mg users had an increased risk of all-cause death (HR 1.25, 95% CI 1.05-1.50) in the secondary analysis. The risks of ischemic stroke, intracranial hemorrhage and gastrointestinal hemorrhage were similar between the 2 study groups in both the primary and secondary analyses. For non-valvular AF patients, rivaroxaban 15 mg seemed to be associated with an increased risk of all-cause death compared with dabigatran 110 mg. This was a retrospective data analysis and the results should not be over-interpreted to guide the choice of different NOACs.