A Comparative Evaluation of Adverse Drug Events and Incidence of Stroke amongst the Target Specific Oral Anticoagulants

Background: Dabigatran, rivaroxaban, and apixaban have similar bleeding and stroke risks compared to warfarin, but have never been evaluated against one another in the same respect. Objective: To evaluate the incidence of bleeding and stroke when using target specific oral anticoagulants (TSOAC).

Methods: Retrospective, observational study design. IRB approval was obtained. Inclusion criteria included anticoagulation clinic enrollment, age > 18 years, medication adherence. Exclusion criteria included prior use of TSOAC, renal/liver dysfunction, valvular disease. Oral administration of dabigatran 150 mg twice daily, rivaroxaban 20 mg daily and apixaban 5 mg twice daily were examined. Coprimary outcomes were the number of bleeding and stroke events with dabigatran and rivaroxaban use. Apixaban was excluded due to a small sample size. Secondary outcomes included the number of non-bleeding ADRs, drug-drug interactions, all cause hospitalizations, and time to occurrence of bleeding or non-bleeding ADRs and to occurrence of stroke events.

Results: A total of 176 patients were analyzed. A non-significant trend in favor of rivaroxaban was found for bleeding events (p = 0.134). One patient receiving dabigatran experienced a stroke. A higher, nonsignificant trend of hospitalizations due to bleeding or stroke was found in the dabigatran group (p = 0.089). A significantly greater incidence of non-bleeding ADRs was demonstrated in the dabigatran group (p < 0.001) as well as rate of discontinuation of therapy (p < 0.001).

Conclusions: Dabigatran and rivaroxaban have similar rates of stroke and bleeding, yet rivaroxaban is better tolerated due to less non-bleeding events, less rate of discontinuation, and trend towards a decrease in hospitalizations due to bleeding or stroke.