Apixaban and warfarin are equally effective in reducing the incidence of stroke and thromboembolic events among patients with atrial fibrillation, according to findings from a systematic review and meta-analysis published in Stroke.
A total of 16 studies with 170,814 apixaban-treated patients were included in the final analysis. In 4 studies, apixaban was compared with warfarin; in 8 studies, apixaban use was compared with warfarin, dabigatran, and rivaroxaban; and in the remaining 4 studies, apixaban was compared with both dabigatran and rivaroxaban.
According to the findings from the meta-analysis, a regular dose of apixaban was more effective in reducing any thromboembolic event (odds ratio [OR], 0.77; 95% CI, 0.64-0.93) than warfarin. Despite this apparent benefit, the patients in the reduced dose subgroup had an overall 27% increase in risk for any thromboembolic event (P <.0001).
Risk for hemorrhagic stroke was also significantly reduced among patients taking apixaban (36% relative risk reduction [RRR]; P =.0003). In addition, the risks for major bleeding (OR, 0.62; 95% CI, 0.51-0.75) and any bleeding (P =.009) were lower in the apixaban vs warfarin groups. Nonsignificant differences were found between apixaban and dabigatran in the risk for any thromboembolic event (P =.30).
In addition, patients taking apixaban had lower gastrointestinal bleeding (57% RRR; P <.00001) and lower rates of any bleeding (31% RRR; P <.00001) compared with patients taking dabigatran. Although rivaroxaban was superior to apixaban in terms of a lower risk for any thromboembolic event (OR, 1.27; 95% CI, 1.13-1.43) and stroke (OR, 1.31; 95% CI, 1.15-1.50), apixaban was associated with a lower risk for major bleeding compared with rivaroxaban (46% RRR; P <.00001).
A limitation associated with this study included the investigators’ inability to account for the quality of anticoagulation control or patient adherence to nonvitamin K antagonist oral anticoagulants.
Overall, the similar efficacy and safety profiles of the studied therapies “suggest that in the context of currently available [real-world studies] evidence apixaban could possibly represent the best alternative for [oral anticoagulant therapy]…for many patients with [atrial fibrillation].”
Proietti M, Romanazzi I, Romiti GF, Farcomeni A, Lip GYH. Real-world use of apixaban for stroke prevention in atrial fibrillation: a systematic review and meta-analysis [published online November 22, 2017]. Stroke. doi:10.1161/STROKEAHA.117.018395