Effect of rivaroxaban monotherapy vs. combination with anti-platelet therapy in patients with atrial fibrillation and stable coronary artery disease across different body mass index categories

Abstract

Abstract Background The AFIRE (Atrial Fibrillation and Ischemic Events With Rivaroxaban in Patients With Stable Coronary Artery Disease) trial showed both noninferiority for efficacy and superiority for safety endpoints of rivaroxaban monotherapy compared to rivaroxaban plus antiplatelet therapy (combination therapy) in patients with atrial fibrillation (AF) and stable coronary artery disease (CAD). However, no accumulating evidence regarding efficacy and safety of these fixed-dose direct oral anticoagulant therapy was available in underweight and obese patients. Purpose The aim of this post-hoc analysis of the AFIRE trial was to evaluate outcomes of rivaroxaban monotherapy (vs. combination therapy) in patients with AF and stable CAD across body mass index (BMI) categories. Methods Patients were categorized into groups 1 (underweight: BMI of <18.5 kg/m2), 2 (normal: BMI of 18.5 to <25 kg/m2), 3 (overweight: BMI of 25 to <30 kg/m2), and 4 (obesity: BMI of ≥30 kg/m2). Efficacy (a composite of all-cause death, myocardial infarction, unstable angina requiring revascularization, stroke, or systemic embolism) and safety (major bleeding defined according to International Society on Thrombosis and Haemostasis criteria) were compared between rivaroxaban monotherapy and combination therapy across BMI categories. Results We analyzed 2,054 patients with a median age of 75.0 (interquartile range [IQR], 69 to 80)) years old and CHA2DS2-VASc of 4 (IQR, 3 to 5). Group 1 through 4 included 72 (3.5%), 1,158 (56.4%), 680 (33.1%), 144 (7.0%) patients and 62.3%, 52.3%, 36.2%, and 30.3% were received reduced dose of rivaroxaban, respectively. Although the sample sizes for group 1 and 4 were limited, monotherapy was superior to combination therapy for efficacy in group 2 (hazard ratio [HR], 0.64; 95% CI, 0.44 to 0.95) and safety in group 3 (HR, 0.25; 95% CI, 0.10 to 0.62), whereas a significant difference in the endpoints was not observed in the other BMI categories. Impact of monotherapy on endpoints did not have a significant interaction in BMI. Conclusions Rivaroxaban monotherapy had similar effect on prognosis across all BMI categories in patients with AF and stable CAD. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): The Japan Cardiovascular Research Foundation based on a contract with Bayer Yakuhin, Ltd