P4820Benefit-risk of rivaroxaban 20 or 15mg compared to vitamin-K antagonists in patients with non-valvular atrial fibrillation: a cohort study in the French nationwide claims database

Background: Real-life benefits and risks of direct-acting oral anticoagulants for non-valvular atrial fibrillation (NVAF) remain uncertain. Rivaroxaban 20mg (R20) is the standard dose, rivaroxaban 15mg (R15) is recommended for patients with moderate or severe renal failure but not if renal clearance is below 15 ml/min. Purpose: To compare the one-year risk of major events in new users of R20 and R15 versus vitamin K antagonists (VKA) in patients with NVAF in real-life setting. Methods: Cohorts of new users of R20, R15 or VKA for NVAF in 2013–2014 were identified in the SNDS (Système National des Données de Santé) 66 million persons nationwide French claims database and followed for one year. NVAF was defined from full coverage, hospitalization or procedure for atrial fibrillation without rheumatic valve disease or valve replacement (3-year database history). Rivaroxaban and VKA patients were 1:1 matched on gender, age, date of the first drug dispensing, and high-dimensional propensity score including major arterial thrombosis and bleeding risk factors. Hazard Ratios (HR) [95% Confidence Interval (CI)] were estimated over the one-year follow-up during first prescribed anticoagulant exposure, using Cox proportional hazards risk or Fine and Gray models.