AbstractBackgroundIn trials of patients with atrial fibrillation (AF), non–vitamin K antagonist oral anticoagulants (NOACs) were not inferior to warfarin for thromboembolic and bleeding events. However, there are scant data comparing the efficacy and safety of NOACs in patients with AF with that of well-controlled warfarin treatment in such patients.ObjectivesTo compare total bleeding and thromboembolic events in patients with AF who received NOACs, with the same events in those who received well-controlled warfarin treatment.MethodsWe used retrospective data from patients with AF who received NOACs or well-controlled warfarin at the Central Chest Institute of Thailand from January 2017 to December 2019. The primary outcome was total bleeding or thromboembolic events or both. The secondary outcome was all-cause mortality, total bleeding events including major or minor bleeding, and thromboembolic events including ischemic stroke or systemic embolization.ResultsWe included data from 180 patients with AF, 90 who received NOACs and 90 who received well-controlled warfarin. The average time in the therapeutic range for those who received warfarin was 84.9% ± 9.8%. The patients who received well-controlled warfarin had more frequent thromboembolic or total bleeding events or both than those who received NOACs (odds ratio [OR] 3.17; 95% confidence interval [CI] 2.27–4.07;P= 0.01). There were more minor bleeding events in those who received well-controlled warfarin (OR 3.75; 95% CI 2.79–4.71;P= 0.01). However, there was no significant difference in thromboembolic events, major bleeding, or all-cause mortality between the 2 groups.ConclusionsThai patients with AF who received NOACs had less thromboembolic or total bleeding events than those who received well-controlled warfarin treatment.