Apixaban for Secondary Stroke Prevention: Coexistant Cerebral Atherosclerosis May Increase Recurrent Strokes

BACKGROUND AND PURPOSE: Oral anticoagulants are needed in stroke patients with atrial fibrillation (AF) for the prevention of recurrent stroke. However, the risk of major events or bleeding may be greater in stroke patients than in those without, because the presence of cerebral atherosclerosis or small vessel disease may increase these risks. This study aimed to investigate the outcomes of apixaban-treated stroke patients with AF and assess whether these factors are associated with the outcome. METHODS: This was a sub-analysis of stroke patients with AF enrolled in a prospective, open-label, multicenter, post-marketing surveillance study in South Korea, who were treated with apixaban and underwent magnetic resonance imaging (MRI) (Clinical trial registration: NCT01885598). RESULTS: A total of 651 patients (mean age, 72.5±8.7 years) received apixaban for a mean duration of 82.7±37.4 weeks. Fifty-three bleeding events occurred in 39 patients (6.0%), and 10 (1.5%) experienced major bleeding. Seventeen patients (2.6%) had major events (stroke, n=15, 2.3%; all ischemic), systemic embolism (n=1, 0.2%), and death (n=3, 0.5%). MRI data showed no significant association between white matter ischemic changes and microbleeds, and major events or bleeding. Patients with cerebral atherosclerotic lesions had a higher rate of major events than those without (4.6% [n=10/219] vs. 1.7% [n=7/409], P=0.0357), which partly explains the increased prevalence of major outcomes in this group versus patients without stroke (0.7%, P=0.0002). CONCLUSIONS: Apixaban is generally safe for patients with ischemic stroke. Increased primary outcomes in stroke patients may in part be attributed to the presence of cerebral atherosclerotic lesions, suggesting that further studies are needed to establish therapeutic strategies in this population.