P2569Anticoagulation plus antiplatelet therapy for atrial fibrillation: Cost-Utility of combination therapy with non-Vitamin K oral anticoagulants versus Warfarin

Background: Emerging evidence indicates combination therapy with anticoagulants and antiplatelet agents for atrial fibrillation (AF) will be increasingly required. Numerous studies compare efficacy and cost-effectiveness of anticoagulation alone in AF; non-vitamin K oral anticoagulants (NOACs) versus warfarin. However, addition of antiplatelet agents with their potential for decreased thromboembolic stroke counter-balanced by increased bleeding risk has received little attention. Therefore, we evaluated the cost-utility of combination therapy. Method: We obtained event estimates from a recent meta-analysis designed to compare NOACs with warfarin in patients with AF. Specifically, we examined patient subgroups that received antiplatelet therapy in addition to anticoagulation. A decision tree was constructed and populated with utilities derived from the literature and costs from the German health care system. We used a one-year time horizon because, for most cases, antiplatelet therapy will be for a finite duration. We calculated incremental cost-effectiveness ratio (ICER) per quality-adjusted life year (QALY). Sensitivity analysis was performed on NOAC costs. Their relatively high costs could exert considerable influence. Additional sensitivity analyses were conducted to examine variation in therapy costs for stroke, myocardial infarction, and major bleeding.