Use of rivaroxaban attenuates renal function impairment in patients with atrial fibrillation: insights of the EMIR study.

Background: In atrial fibrillation (AF) patients on vitamin K antagonists, a progressive deterioration of renal function is common but there is limited evidence with long-term use of rivaroxaban. Herein, we investigated the change in renal function in AF patients after 2 years of rivaroxaban treatment.

Methods: The EMIR registry is an observational and multicentre study including AF patients treated with rivaroxaban for at least 6 months prior to inclusion. Changes in analytical parameters were recorded during 2 years of follow-up. Renal function was estimated using the Cockroft-Gault equation.

Results: 1433 patients (638, 44.5% women, mean age of 74.2 ± 9.7 years) were included. Creatinine clearance (CrCl) was available at baseline and at 2 years in 1085 patients. At inclusion, 33.2% of patients had impaired renal function (CrCl <60 ml/min). At 2 years, we were not able to find changes in the proportion of patients with impaired renal function, which increased to 34.6% (p = 0.290). However, the baseline mean CrCl was 76.0 ± 30.5 ml/min and slightly improved at 2 years (77.0 ± 31.8 ml/min; p = 0.014). Overall, the proportion of patients with CrCl <60 ml/min at baseline that had CrCl ≥60 ml/min at 2 years was significantly higher compared to that of patients with CrCl ≥60 ml/min at baseline and CrCl <60 ml/min after (22.2% vs. 13.1%; p < 0.001) CONCLUSIONS: In AF patients on long-term rivaroxaban therapy, a decrease in renal function was not observed. We even observed a slight improvement in the patients with renal impairment. These results reinforce the idea that rivaroxaban may be a safe option even in patients with renal impairment.