Oral anticoagulants in extremely-high-risk, very elderly (>90 years) patients with atrial fibrillation

Background: The prevalence and incidence of atrial fibrillation (AF) increase with age. However, older patients often are denied oral anticoagulation (OAC), especially if they are “very elderly” (age ≥90 years) and perceived to be high risk for bleeding, for example, those with a history of intracranial hemorrhage (ICH), gastrointestinal bleeding (GIB), or chronic kidney disease. Objective: The purpose of this study was to investigate the effectiveness and safety of OAC in this high-risk, very elderly group. Methods: We used the Taiwan National Health Insurance Research Database to identify high-risk, very elderly subjects taking OAC, either warfarin or a non–vitamin K antagonist oral anticoagulant (NOAC), and compared them to non-OAC users for the composite net clinical endpoint of ischemic stroke, ICH, major bleeding, or mortality. Results: We studied 7362 subjects (mean age 92.5 years), of whom 1737 were taking NOACs, 670 warfarin, and 4955 non-OACs. Compared to non-OACs, warfarin was associated with a higher risk of the composite endpoint (adjusted hazard ratio [aHR] 1.163; 95% confidence interval [CI] 1.052–1.287), whereas NOACs were associated with a lower risk (aHR 0.763; 95% CI 0.702–0.830). After propensity matching, NOACs were associated with a lower risk of events compared to non-OACs or warfarin, whereas warfarin had a similar risk compared to non-OACs. Conclusion: Warfarin was associated with a similar or even higher risk of composite clinical outcomes compared to non-OACs. NOACs were associated with a lower risk of composite endpoint compared to warfarin or non-OACs, and their use still should be considered in these high-risk, very elderly AF patients.