Trends in antiarrhythmic drug use after marketing authorization of dronedarone: comparison between Emilia Romagna (Italy) and Sweden

Abstract

Our aim was to evaluate whether dronedarone authorization impacts antiarrhythmic drug prescribing in Sweden and Emilia Romagna (Italy). Prescriptions of classes I and III antiarrhythmics, expressed as defined daily doses per thousand inhabitants per day (DDD/TID) were monthly using information collected from pharmacy-reimbursed databases. Interrupted time series analysis was applied to compare prescription data over the 2009-2011 period. In Emilia Romagna, the overall consumption of antiarrhythmics was six times as high as in Sweden (7.6 vs. 1.2 DDD/TID). In the first year on the market, dronedarone represented 1.0 % in Italy and 10.7 % in Sweden of the overall antiarrhythmic prescriptions. In Sweden, dronedarone authorization generated an increase in the prescription trend of antiarrhythmics (trend change +0.02; p < 0.001) without variation in amiodarone use In Emilia Romagna, dronedarone marketing did not influence the prescription pattern of either overall antiarrhythmics or amiodarone. Emilia Romagna and Sweden substantially differ in terms of overall antiarrhythmic use. Although clinical guidelines place dronedarone among first-choice treatments for atrial fibrillation, amiodarone prescribing was not affected in either country by the entry of dronedarone, probably due to a cautious approach by clinicians in line with regulatory recommendations and safety warnings.