Effectiveness and safety of secondary prevention of non-vitamin K oral anticoagulants use by drug type in Asian patients

Background: Although widely used in clinical fields, real-world data on the role of warfarin and non-vitamin K oral anticoagulants (NOACs) for the secondary prevention of thromboembolic complications in ischemic stroke patients with nonvalvular atrial fibrillation (NVAF) are scarce. Aims: This retrospective cohort study compared the effectiveness and safety of secondary prevention of NOAC and warfarin in ischemic stroke patients with NVAF. Methods: From the Korean National Health Insurance Service Database, we included 16,762 oral anticoagulants-naive acute ischemic stroke patients with NVAF between July 2016 and June 2019. The main outcomes included ischemic stroke, systemic embolism, major bleeding, and all-cause of death. Results: In total, 1717 warfarin and 15,025 NOAC users were included in the analysis. After 1:8 propensity score matching, during the observation period, all types of NOACs had a significantly lower risk of ischemic stroke and systemic embolism than warfarin (edoxaban: adjusted hazard ratio [aHR], 0.80; 95% confidence interval [CI], 0.68–0.93, rivaroxaban: aHR, 0.82; 95% CI, 0.70–0.96, apixaban: aHR, 0.79; 95% CI, 0.69–0.91, and dabigatran: aHR, 0.82; 95% CI, 0.69–0.97). Edoxaban (aHR, 0.77; 95% CI, 0.62–0.96), apixaban (aHR, 0.73; 95% CI, 0.60–0.90), and dabigatran (aHR, 0.66; 95% CI, 0.51–0.86) had lower risks of major bleeding and all-cause of death. Conclusions: All NOACs were more effective than warfarin in the secondary prevention of thromboembolic complications in ischemic stroke patients with NVAF. Except for rivaroxaban, most NOACs demonstrated a lower risk of major bleeding and all-cause of death than warfarin.