Evaluation of oral anticoagulants in atrial fibrillation patients over 80 years of age with nonsevere frailty

Background The safety and efficacy of an oral anticoagulant (OAC) treatment and the difference between direct OACs (DOACs) and warfarin in nonsevere frail elderly patients with AF are unclear. Methods This was a retrospective and observational study of 354 patients over 80 years of age with nonsevere frailty who were diagnosed with AF and treated with OACs. Nonsevere frailty was defined as a clinical frailty scale score of <7. Bleeding and thromboembolic events during the OAC treatment were followed up. Results Of 354 patients enrolled, 273 (77.1%) received DOACs and 81 (22.9%) received warfarin. Of 273 patients receiving DOACs, there were 210 (76.9%) prescribed with appropriate doses of DOACs. Of 81 warfarin‐treated patients, 53 (65.4%) were prescribed an appropriate dose of warfarin. During a follow‐up of 33.1 (14.0‐51.0) months, 15 patients (1.5/100 person‐years) had bleeding events and 10 (1.0/100 person‐years) had thromboembolic events while on an OAC treatment. The incidence ratio of bleeding events in patients receiving DOACs was lower than that in those receiving warfarin (1.0/100 person‐years vs 2.9/100 person‐years, hazard ratio [HR]: 0.26, 95% confidence interval [CI]: 0.07‐0.91, P = .036). There was no significant difference in the incidence of thromboembolic events between the DOAC and warfarin treatment groups (0.88/100 person‐years vs 1.4/100 person‐years, HR: 0.63, 95% CI: 0.16‐2.57, P = .52). Conclusions OACs are substantially safe and effective for preventing thromboembolic events in nonsevere frail patients over 80 years of age. Particularly, DOACs can be used more safely than warfarin.