Prevalence of use of benzodiazepines and related drugs in seven european databases: A cross-national descriptive study from the protect-eu project

Background: Benzodiazepines use has been a matter of concern worldwide. Although many drug utilization studies have been published, only a few were designed for direct cross-national comparison. Objectives: This study aims at describing and comparing benzodiazepines use and trends in five European countries. Additionally, the use of benzodiazepinerelated drugs ('Z-drugs') was evaluated. Methods: We calculated crude and standardized prevalence rates of drug use by calendar year from 2001 to 2009, in seven European health care electronic databases (DB). We also calculated age and sex specific prevalence rates and the distribution by benzodiazepine- anxiolytics (N05BA), benzodiazepine-hypnotics (N05CD) and benzodiazepine-related drugs (N05CF). Indication and number of prescriptions issued in 2008 were also examined. Results: The age- and sex-standardized prevalence of use in 2008 was highest in BIFAP, Spanish DB (1,598 per 10,000 p-y) whereas Bavarian Claims, German DB (477 per 10,000 p-y) yielded the lowest. Prevalence in the Spanish DB increased over the study period, while a decreased was showed in the Danish, Bavarian and Dutch-NPCRD, and remained stable in the two UK DB and the Dutch-AHC DB. Use of anxiolytics outweighed that of hypnotics in the Spanish, Dutch and Bavarian DB, but the reverse was shown in the UK and Denmark. In people over 50 years of age, prevalence rates were consistently twofold higher in women than in men in all DB. In 2008, the percentage of patients with ≥ 4 four prescriptions ranged from 16% to 46%. Conclusions: This study shows that analysing drug utilization in different DB according to a common protocol is feasible and valuable. Moreover it adds up to the knowledge of the real prescribing/dispensing patterns of these drugs in primary care. International comparisons are desirable as they may play an important role in pharmacovigilance.