European Surveillance of Antimicrobial Consumption (ESAC): outpatient antibiotic use in Europe

BACKGROUND: Data on more than a decade of outpatient quinolone use were collected from 33 European countries within the European Surveillance of Antimicrobial Consumption (ESAC) project, funded by the European Centre for Disease Prevention and Control (ECDC). METHODS: For the period 1997-2009, data on outpatient use of systemic quinolones aggregated at the level of the active substance were collected using the Anatomical Therapeutic Chemical (ATC)/defined daily dose (DDD) method (WHO, version 2011), and expressed in DDD and packages per 1000 inhabitants per day (DID and PID, respectively). Using a classification based on pharmacokinetic and in vitro potency profiles, quinolone use was analysed with regard to trends over time, seasonal variation and composition. RESULTS: Total outpatient quinolone use in 2009 varied by a factor of 7.5 between the country with the highest (Italy, 3.61 DID) and the country with the lowest (the UK, 0.48 DID) quinolone use. The second-generation quinolones accounted for >50% of quinolone use (mainly ciprofloxacin), except for Croatia, where first-generation quinolones (mainly norfloxacin) were mostly used. A significant increase in outpatient quinolone use was found for Europe, as well as a large seasonal variation, which increased significantly over time from 1997 to 2009. Relative use of third-generation quinolones significantly increased over time with respect to the use of second-generation quinolones, while the relative use of both significantly increased with respect to the first-generation quinolones. Levofloxacin and moxifloxacin (respiratory quinolones) represented >10% of quinolone outpatient use in 17 countries, with extreme seasonal variation in all countries. CONCLUSIONS: There was a substantial increase and change in the pattern of quinolone use between 1997 and 2009, a period during which quinolones that are effective for the treatment of respiratory tract infections were introduced. These quinolones are not the first-line antibiotics for this indication and their use should generally be limited, and quinolones should ideally show no substantial seasonal variation in terms of their use.