Background: In patients with atrial fibrillation (AF) who survive an anticoagulant-related intracranial hemorrhage (ICH), the benefits of restarting oral anticoagulation (OAC) remain unclear.
Objective: In this study, we sought to determine the effectiveness and safety associated with resumption of OAC in atrial fibrillation patients who survive an ICH.
Methods: Using 2010-2016 Medicare claims data, we identified patients with non-valvular AF who experienced an OAC-related ICH and survived at least 6 weeks after the ICH (n = 1502). The primary outcomes included the composite of ischemic stroke and transient ischemic attack (TIA), thromboembolism (TE), a composite of ischemic stroke/TIA and TE, recurrent ICH, and all-cause mortality. We constructed Cox proportional hazard models to evaluate the association between post-ICH OAC resumption, which was measured in a time-dependent manner, and the risk of primary outcomes, while controlling for a comprehensive list of covariates.
Results: Among patients who survived an ICH, 69% reinitiated OAC within 6 weeks of the event, and among those who resumed OAC, 83% restarted warfarin. There was no significant difference in the risk of ischemic stroke/TIA (hazard ratio [HR] 0.87, 95% confidence interval [CI] 0.62-1.21), TE (HR 0.85, 95% CI 0.55-1.32), and ischemic stroke/TIA/TE (HR 0.81, 95% CI 0.61-1.07) between post-ICH OAC use and non-use. Post-ICH OAC use was associated with a lower risk of recurrent ICH (HR 0.62, 95% CI 0.41-0.95) and all-cause mortality (HR 0.48, 95% CI 0.37-0.62) compared with non-OAC use.
Conclusions: In AF patients who survived an ICH, restarting OAC was not associated with a greater risk of recurrent ICH. Evidence from randomized controlled studies is needed to further clarify the clinical benefit of restarting OAC in this high-risk population. Further evaluation of which individuals benefit from restarting OAC is also needed to provide more clinical guidance.