P4821Use of novel oral anticoagulants in patients with atrial fibrillation and moderate to severe renal dysfunction: findings from a prospective national registry

Abstract

Background: We aimed to prospectively evaluate the clinical characteristics and outcomes of atrial fibrillation (AF) patients with renal dysfunction who receive NOACS with reduced renal elimination (i.e. apixaban or rivaroxaban) in a multicenter national registry. Methods: The study population comprised 4523 AF patients with eGFR 15-60 ml/min who were recruited to a prospective national registry involving 18 cardiology, medicine, and geriatric departments in Israel. All patients were prospectively followed-up for clinical events, compliance, and dosing adjustments, over a mean period of 2 years. Results: Mean eGFR of study patients was 37 ml/min, and 35% had severe renal dysfunction (eGFR 15-30 ml/min). Low dose apixaban (2.5 mg bid) and rivaroxaban (15 mg) were inappropriately prescribed to 70% and 33% of study patients, respectively (p<0.001 [Figure: left panel]). After propensity score matching, (Figure presented) NOAC under-dosing was associated with significantly higher rates of stroke, systemic embolism or death (23%) compared to appropriate-dose NOACs (12%) and warfarin (13%; log-rank p=0.03 [Figure: right panel]). Appropriate NOAC dosing was associated with reduced bleeding rates compared to warfarin (log-rank p=0.003). Conclusion: Our data from a prospective national registry show a very high rate of NOAC under-dosing in patients with advanced renal dysfunction, which is associated with increased risk of adverse events. Appropriate dosing appears to be effective and safe in this high-risk population.