Increasing use of medicines in elderly persons: a five-year follow-up of the Kuopio 75+Study

Abstract

Objective: The aim of this study was to describe the changes in medicine use, polypharmacy and excessive polypharmacy between 1998 and 2003 among a cohort of elderly Finns.

Methods: For this prospective follow-up study, a random sample of 700 participants aged >or=75 years was drawn from the City of Kuopio, Finland. Of them, 601 participated in the study at baseline in 1998. The changes in medicine use among the survivors (n=339), who were re-examined in 2003, were recorded and are described here. Statistical significance of changes in medicine use was evaluated by Student's paired-samples and independent-samples t-test and Fisher's exact test.

Results: From 1998 to 2003, the mean number of medicines in use per individual increased from 6.3 to 7.5 (p<0.001). The prevalence of polypharmacy (>5 medicines in use) increased from 54% to 67% and excessive polypharmacy (>or=10 medicines in use) from 19% to 28%. The increase was due to increased use of regularly taken medicines, whereas the use of medicines taken as needed decreased during the follow-up in both sexes. At the time of follow-up survey, persons in institutional care used significantly more medicines (10.9) than community-dwelling elderly persons (7.0) (p<0.001). Central nervous system medicines and cardiovascular medicines were the most commonly used medicines in both years.

Conclusion: The number of medicines and the prevalence of polypharmacy and excessive polypharmacy increases with advancing age. In order to avoid possible harmful effects and to optimize medication it is necessary to assess the medication regimen at regular intervals.