Acute renal failure in patients treated with dronedarone or amiodarone: a large population-based cohort study in Italy.

Purpose: Causes of ARF are numerous including drugs. In 2012, spontaneous reporting showed a possible association between dronedarone and ARF. To further investigate such association, a retrospective cohort study on health-service claim databases was performed taking amiodarone as comparison.

Methods: All patients receiving new prescription of amiodarone or dronedarone between September 2010 and December 2012 were selected. Cox regression models to estimate the hazard ratios (HRs), with 95 % confidence intervals (CIs), for dronedarone versus amiodarone were performed. HRs were calculated: (i) for the entire cohort; (ii) for matched cohorts using propensity score; (iii) and high-dimensional propensity score.

Results: New users without previous episodes of ARF were 56,739 and 1761 on dronedarone and 54,978 on amiodarone. After 1:1 matching for propensity score, new users with dronedarone and amiodarone were 1467 and 1467, respectively. The cumulative incidence rate of ARF was 1.6 % (95 % CI 0.7-3.6 %) among dronedarone group and 2.3 % (1.0-5.1 %) among amiodarone group (p from log rank test = 0.4884). The unadjusted HR of ARF was 0.34 (0.18-0.64) in dronedarone new users compared to amiodarone; in propensity score matched cohort, it was 0.75 (0.26-2.16), and in high-dimensional propensity score, it was 0.83 (0.25-2.73).

Conclusions: This large community-based study did not confirm the signal of an increased nephrotoxicity from dronedarone compared to amiodarone. Nevertheless, given the increasing number of reports collected from pharmacovigilance databases worldwide on this association, it is advisable for clinicians and patients to be aware of the possible kidney damage due to dronedarone in order to improve clinical outcomes with early intervention.