Outpatient antibiotic use in France between 2000 and 2010: after the nationwide campaign, it is time to focus on the elderly.

Antibiotic overconsumption is the main force driving the emergence of multidrug-resistant bacterial strains. To promote better antibiotic use in France, a nationwide campaign has been run every year from October to March since 2002. In 2007, it was shown that winter outpatient antibiotic consumption had decreased by 26.5% compared to the 2000-2002 baseline period. Here, we quantified outpatient antibiotic use between 2000 and 2010 as a follow-up analysis of the nationwide campaign. Reimbursed outpatient antibiotic prescriptions were extracted from computerized French National Health Insurance databases. Entire series and age group and antibiotic class analyses were computed. Time series analyses used autoregressive moving-average models with exogenous variables and intervention functions. Two periods were considered: October to March "campaign" periods and April to September "warm" periods. Compared to the precampaign (2000-2002) baseline period, the numbers of weekly antibiotic prescriptions per 1,000 inhabitants during campaign periods decreased until winter 2006 to 2007 (-30% [95% confidence interval {CI}, -36.3 to -23.8%]; P < 0.001) and then stabilized except for individuals >60 years of age, for whom prescriptions reached the precampaign level. During the warm periods from April to September, no significant differences were estimated compared to the baseline level for the entire series, but seniors had an increasing trend that became significant as of 2005, reaching +21% (95% CI, +12.9 to +29.6%) in 2009 (P < 0.0001). These results highlight the need for a better understanding of antibiotic use by the elderly, requiring research with targeted and tailored public health actions for this population.