In adults with atrial fibrillation (AF), antiarrhythmic drug therapy is commonly associated with adverse events and substantial health care resource use, prompting comparisons between commonly prescribed agents. In the Journal of the American Heart Association findings are reported from a retrospective observational study comparing adverse events and health care utilization among patients with AF treated with dronedarone versus amiodarone.

The analysis included adults with AF who initiated dronedarone or amiodarone between January 1, 2010, and September 30, 2021, using Optum’s deidentified Clinformatics Data Mart Database. Patients were propensity score matched 1:1, resulting in 12,210 dronedarone-treated patients paired with 12,210 amiodarone-treated patients. Outcomes included adverse events described in Food and Drug Administration (FDA) labeling and reported in the FDA Adverse Event Reporting System, as well as all-cause and cardiovascular-related health care resource use. Generalized linear models with a Poisson distribution were used to compare event rates, excluding patients with baseline events.

During follow-up, dronedarone was associated with lower event rates of any cardiac and vascular adverse event (rate ratio, 0.71; 95% CI, 0.69–0.72), any respiratory adverse event (0.65; 95% CI, 0.63–0.66), and any gastrointestinal or hepatobiliary adverse event (0.81; 95% CI, 0.79–0.84). All-cause hospitalizations (0.69; 95% CI, 0.67–0.71) and all-cause outpatient visits (0.87; 95% CI, 0.87–0.87) were also lower with dronedarone. Although the incidence of cardiovascular-related hospitalization was higher with dronedarone, event rates were not statistically different, while cardiovascular-related outpatient visits were reduced (0.95; 95% CI, 0.94–0.96).

Overall, this observational analysis found lower adverse event rates and reduced health care resource use among patients with AF treated with dronedarone compared with amiodarone.