Efficacy and Safety of Dabigatran Compared With Warfarin in Relation to Baseline Renal Function in Patients With Atrial Fibrillation

Abstract

Background—: Renal impairment increases the risk of stroke and bleeding in patients with atrial fibrillation. In the Randomized Evaluation of Long-Term Anticoagulant Therapy (RELY) trial, dabigatran, with ≈80% renal elimination, displayed superiority over warfarin for prevention of stroke and systemic embolism in the 150-mg dose and significantly less major bleeding in the 110-mg dose in 18 113 patients with nonvalvular atrial fibrillation. This prespecified study investigated these outcomes in relation to renal function. Methods and Results—: Glomerular filtration rate was estimated with the Cockcroft-Gault, Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), and Modification of Diet in Renal Disease (MDRD) equations in all randomized patients with available creatinine at baseline (n=17 951), and cystatin C–based glomerular filtration rate was estimated in a subpopulation with measurements available (n=6190). A glomerular filtration rate ≥80, 50 to P <0.05). The relative reduction in major bleeding with either dabigatran dose compared with warfarin was greater in patients with glomerular filtration rate ≥80 mL/min. Conclusions—: The efficacy of both dosages of dabigatran was consistent with the overall trial irrespective of renal function. However, with the CKD-EPI and MDRD equations, both dabigatran dosages displayed significantly lower rates of major bleeding in patients with glomerular filtration rate ≥80 mL/min. Clinical Trial Registration—: URL: http://www.clinicaltrials.gov . Unique identifier: NCT00262600.