Abstract 249: Medical Cost Avoidance among the General and Elderly Atrial Fibrillation Populations Differs According to Specific Anticoagulant Use, Based on the ARISTOTLE and RE-LY Trials

Abstract

Introduction: The randomized ARISTOTLE and RE-LY clinical trials demonstrated that the new oral anticoagulants (NOACs) apixaban and dabigatran were effective and safe options for stroke prevention among non-valvular atrial fibrillation (AF) patients. It is unclear how the use of NOACs for the treatment of AF affects total medical costs. Hypothesis: This study evaluates the hypothesis that medical costs associated with the use of apixaban and dabigatran vs. warfarin are different among the general and elderly AF populations. Methods: Clinical event rates in patients receiving warfarin, apixaban, and dabigatran were estimated for the general and elderly (age ≥ 75 years) AF patient populations. Event rates associated with warfarin were calculated as weighted averages from NOAC trials among AF patients; NOAC rates were estimated by adjusting trial hazard ratios to these weighted averages. Annual incremental costs among patients with clinical events from the US payer perspective were obtained from published literature and inflation adjusted to 2010 cost levels. Medical cost avoidance was evaluated for each NOAC vs. warfarin. Results: Compared to warfarin, apixaban-mediated total medical cost reductions (Table) in both populations were driven by decreased major bleeding excluding hemorrhagic stroke (MBEHS) and stroke and systemic embolism (SSE). Dabigatran use reduced costs for the general population and increased costs for the elderly population; cost reduction in the general population was primarily due to reduced SSE while cost increase in the elderly population was primarily due to increased MBEHS. MI, PE or DVT, and non-major bleeding each made smaller contributions to the cost differences among both populations. Conclusions: Compared to warfarin, apixaban use may be associated with reduced medical costs in both general and elderly AF populations. Dabigatran use may be associated with a reduction of medical costs in the general AF population, but increased medical costs among the elderly.