Impact of renal function on outcomes with edoxaban in real-world patients with atrial fibrillation a nationwide cohort study

Background and Purpose-Edoxaban is a direct oral factor Xa inhibitor with proven efficacy and safety among patients with atrial fibrillation. Concerns have been raised about an excess of stroke among patients with creatinine clearance (CrCl) >95 mg/mL treated with edoxaban. We assessed the real-world effectiveness and safety of edoxaban in atrial fibrillation patients in relation to CrCl. Methods-In the Korean National Health Insurance Service data during the period from January to December 2016, we identified 9537 edoxaban-treated patients. Effectiveness and safety outcomes were compared between high-dose edoxaban regimen (HDER, 60 mg daily, n=2840) and a propensity score-matched warfarin group (n=2840) and between low-dose edoxaban regimen (LDER, 30 mg daily, n=3016) and matched warfarin group (n=3016). Results-The median follow-up period was 5.0 months (interquartile range, 2-7 months). The mean age was 68 years, and 63% were men in HDER group, and the mean age was 73 years, and 52% were men in LDER group. Compared with warfarin, both HDER and LDER significantly decreased the risk for ischemic stroke or systemic embolism (S/SE; HDER: adjusted hazard ratio [aHR], 0.44; 95% CI, 0.31-0.64; LDER: aHR, 0.57; 95% CI, 0.42-0.78), major bleeding (HDER: aHR, 0.40; 95% CI, 0.26-0.61; LDER: aHR, 0.61; 95% CI, 0.43-0.85), and mortality (HDER: aHR, 0.34; 95% CI, 0.22-0.53; LDER: aHR, 0.55; 95% CI, 0.41-0.73). In patients with CrCl >95 mL/min, the incidence of S/SE was higher with LDER than warfarin and comparable between HDER and warfarin group. There was lower effectiveness for the prevention of S/SE with LDER compared with warfarin at higher CrCl levels (P for interaction=0.023). Conclusions-In real-world practice, both doses of edoxaban were associated with reduced risks for S/SE, major bleeding, and mortality compared with warfarin. LDER had lower effectiveness for the prevention of S/SE compared with warfarin at higher levels of CrCl (>95 mL/min).