Frequency and risk factors of potentially inappropriate medication use in a community-dwelling elderly population:: results from the 3C Study

Objective: To estimate the frequency of potentially inappropriate medication use among community-dwelling elderly subjects and to identify socio-demographic factors associated with this use. Methods: Data were collected in the Three-City Study, a French longitudinal study on vascular factors and cognitive decline. The study population was composed of 9,294 subjects aged 65 years and older, living in the community. Inappropriate medication use was assessed using a list derived from the Beers criteria by a panel of French experts. Results: Nearly 40% of the participants used at least one potentially inappropriate medication: 23.4% used cerebral vasodilators, 9.2% long-acting benzodiazepines and 6.4% drugs with anticholinergic properties. Excluding cerebral vasodilators from the list, the frequency of potentially inappropriate medication use was 21.7%. This use was significantly more frequent among women, older subjects and poorly educated subjects. Adjusted analyses showed that these associations could not be explained by a confounding effect of medical factors. Compared with 13.0% of men with a high educational level, 27.9% of women with a low educational level used at least one potentially inappropriate medication (odds ratio = 2.0; 95% confidence interval: 1.7-2.3). Conclusion: This study is the first attempt to evaluate the frequency of potentially inappropriate medication use in the elderly French population. Female gender and low socio-economic characteristics reduced the chances of receiving optimal pharmacotherapy. The proportion of elderly subjects receiving potentially inappropriate medication was higher than shown in previous studies. This is mainly explained by differences in the use of cerebral vasodilators.