Antibiotic use in ambulatory care in Europe (ESAC data 1997–2002): trends, regional differences and seasonal fluctuations

Purpose: The ESAC project (European Study on Antibiotic Consumption) aims to collect antibiotic-use data through a European network of national surveillance systems. This paper reports on the retrospective data collection in ambulatory care for the period 1997–2002. Methods: Valid data of antibiotic consumption of 24 European countries for 2002 and of 18 countries for the entire 6-year period was classified according to the Anatomical Therapeutic Chemical Classification (ATC) and expressed in defined daily dose (DDD) per 1000 inhabitants per day (DID). Overall and subgroup comparison of antibiotic consumption over time as well as between geographical clusters was performed. Results: Total use of antibiotics in Europe remained at a median level of 20 DID in the period 1997–2002 with a wide variation between countries ranging from 9.8 DID in The Netherlands to 32.2 DID in France. A substantial increase in subclass consumption of co-amoxiclav and fluoroquinolones was noted while the use of narrow-spectrum penicillins, erythromycin, quinolones and sulfonamides decreased. Total consumption as well as seasonal fluctuations showed remarkable geographical clustering with low consumption and low variation between summer and winter in the North, high consumption patterns in the South and a mixed model in the East. Conclusions: Within the ESAC project, valid time series of antibiotic-use data are publicly available now, enabling to improve the study of determinants of use, the evaluation of governmental antibiotic consumption policies and the investigation of the associated emergence of antibiotic resistance.