Current anticoagulant usage patterns and determinants in Korean patients with nonvalvular atrial fibrillation

Purpose: Stroke prevention in patients with atrial fibrillation (AF) is influenced by many factors. Using a contemporary registry, we evaluated variables associated with the use of warfarin or direct oral anticoagulants (OACs). Materials and Methods: In the prospective multicenter CODE-AF registry, 10529 patients with AF were evaluated. Multivariate analyses were performed to identify variables associated with the use of anticoagulants. Results: The mean age of the patients was 66.9±14.4 years, and 64.9% were men. The mean CHA₂DS₂-VASc and HAS-BLED scores were 2.6±1.7 and 1.8±1.1, respectively. In patients with high stroke risk (CHA₂DS₂-VASc ≥2), OACs were used in 83.2%, including direct OAC in 68.8%. The most important factors for non-OAC treatment were end-stage renal disease [odds ratio (OR) 0.27; 95% confidence interval (CI): 0.19–0.40], myocardial infarct (OR 0.53; 95% CI: 0.40–0.72), and major bleeding (OR 0.57; 95% CI: 0.39– 0.84). Female sex (OR 1.40; 95% CI: 1.21–1.61), cancer (OR 1.78; 95% CI: 1.38–2.29), and smoking (OR 1.60; 95% CI: 1.15–2.24) were factors favoring direct OAC use over warfarin. Among patients receiving OACs, the rate of combined antiplatelet agents was 7.8%. However, 73.6% of patients did not have any indication for a combination of antiplatelet agents. Conclusion: Renal disease and history of valvular heart disease were associated with warfarin use, while cancer and smoking status were associated with direct OAC use in high stroke risk patients. The combination of antiplatelet agents with OAC was prescribed in 73.6% of patients without definite indications recommended by guidelines.