A cross-sectional evaluation of the prevalence and detection of predictors of polypharmacy amongst adult in Spain

Objective To investigate the association between polypharmacy and sociodemographic factors as well as health status, determinants of health and healthcare use, illness and use of prescribed medicines amongst adults in Spain. Methods Data from the 2009 European Health Interview Survey in Spain which included 22188 subjects were used. Polypharmacy was defined as the use of five or more prescribed medicines. The association between polypharmacy and several variables was assessed by means of bivariate analysis and logistic regression analysis (adjusted by age and gender). Key findings Amongst study participants, 15.8% were on prescribed polypharmacy (19.3%, women; 10.3%, men (P < 0.001)). A number of sociodemographic factors (e.g. age, gender, educational level), health status factors (e.g. limitation in daily activities, self-perception of health, presence of chronic disease) and other health-related factors (e.g. smoking, alcohol drinking, physical activity) have been studied and have been found to play a role in polypharmacy. Logistic regression analysis provided three variables which together with age could be used to predict polypharmacy. Conclusion In Spain, approximately 16% of people who take medicines are on polypharmacy and this is more frequent in women and amongst older adults. From our study, we can conclude that the variables which can predict a higher likelihood of polypharmacy are, together with age, prescribed antidepressants, and prescribed medicines for back/neck pain and joint pain. This may provide a tool for health professionals to readily assess polypharmacy appropriateness in polymedicated patients.