Vitamin K Antagonists and Direct Oral Anticoagulants in Nonagenarian Patients With Atrial Fibrillation

Abstract Objectives Nonagenarian patients are underrepresented in clinical trials that have evaluated oral anticoagulation in patients with atrial fibrillation (AF). The aim of this study was to assess the pronostic impact of oral anticoagulation in patients with AF age ≥90 years. Design Retrospective multicenter study of nonagenarian patients with AF. Setting and participants A total of 1750 nonagenarian inpatients and outpatients with nonvalvular AF between January 2013 and December 2018 in 3 Spanish health areas were studied. Methods Patients were divided into 3 groups based on antithrombotic therapy: nonoral anticoagulants (30.5%), vitamin-K antagonists (VKAs; 28.6%), and direct oral anticoagulants (DOACs; 40.9%). During a mean follow-up of 23.6 ± 6.6 months, efficacy outcomes (death and embolic events) were evaluated using a Cox regression analysis and safety outcomes (bleeding requiring hospitalization) by competing-risk regression. Results were complemented with a propensity score matching analysis. Results During follow-up, 988 patients died (56.5%), 180 had embolic events (10.3%), and 186 had major bleeding (10.6%). After multivariable adjustment, DOACs were associated with a lower risk of death and embolic events than nonanticoagulation [hazard ratio (HR) 0.75, 95% confidence interval (CI)] 0.61‒0.92), but VKAs were not (HR 0.87, 95% CI 0.72‒1.05). These results were confirmed after propensity score matching analysis. For bleeding, both DOACs and VKAs proved to be associated with a higher risk (HR for DOAC 1.43; 95% CI 0.97‒2.13; HR for VKA 1.94; 95% CI 1.31‒2.88), although findings for DOACs were not statistically significant (P = .074). For intracranial hemorrhage (ICH), only VKAs—not DOACs—presented a higher risk of ICH (HR 4.43; 95% CI 1.48‒13.31). Conclusions and implications In nonagenarian patients with AF, DOACs led to a reduction in mortality and embolic events in comparison with nonanticoagulation. This reduction was not observed with VKAs. Although both DOACs and VKAs increased the risk of bleeding, only VKAs were associated with higher ICH rates.