Risk versus Benefit of Non-Vitamin K Dependent Anticoagulants Compared to Warfarin for the Management of Atrial Fibrillation in the Elderly

Abstract

The objective of this review was to compare the safety and efficacy of dabigatran, rivaroxaban and apixaban to warfarin for the management of atrial fibrillation (AF) in older adults. The prevalence and incidence of AF increase with age. Approximately 5 % of the United States population over the age of sixty-five years and 10 % over the age of seventy-nine years have AF. AF is associated with increased risk for thromboembolic events. Despite the increasing incidence and prevalence of AF in older adults and the risks of thromboembolic events, clinicians often avoid anticoagulants. Specifically with warfarin, the risk of hemorrhage may outweigh the benefit in stroke risk reduction in certain populations. Aspirin, while safer to use, is not as effective as warfarin in stroke risk reduction. Newer non-vitamin K dependent antithrombotic therapies (e.g. dabigatran, rivaroxaban, and apixaban) are redefining thromboprophylaxis of AF. Dabigatran, rivaroxaban, and apixaban are at least as effective as warfarin in stroke risk reduction. With new mechanisms of action and no need for therapeutic drug monitoring, countless new patients are potential candidates for anticoagulation. However patient adherence, lack of a reversal agent, cost, and other safety concerns remain reasons for caution and careful consideration. Furthermore, older adults exhibited greater adverse effects from these agents across the clinical trials. This review will examine the newer anticoagulants safety and efficacy with particular attention to their role in treating older adults with AF. Alternatives to warfarin therapy now exist for thromboprophylaxis of AF. Whether these agents represent advances in overall safety in older adults remains uncertain. More experience and research are needed before endorsing their widespread use as a replacement for warfarin in the geriatric population.