Effects of Medication Assessment as Part of a Comprehensive Geriatric Assessment on Drug Use over a 1-Year Period A Population-Based Intervention Study

Background: High drug consumption among the elderly and inappropriate prescribing practices increase the risk of adverse drug effects in this population. This risk may be decreased by conducting, for example, a medication review alone or as part of a comprehensive geriatric assessment (CGA); however, little is known about the fate of the changes in medication made as a result of the CGA or medication review. Objective: To study the performance of the CGA with regards to medication changes and to determine the persistence of these changes over a 1-year period. Methods: This study was a population-based intervention study. A random sample of 1000 elderly (age >= 75 years) was randomized either to a CGA group or to a control group. Home-dwelling patients from these groups (n = 331 and n = 313 for intervention and control groups, respectively) were analysed in this study. Study nurses collected information on medication at study entry and 1 year later in both groups; in the intervention group, study physicians assessed, and changed when appropriate, the medication at study entry. The medication changes and their persistence over 1 year were then evaluated. Results: Medication changes were more frequent in the intervention group than in the control group. Regular medication was changed during follow-up in 277 (83.7%) and in 228 (72.8%) [odds ratio (OR) 1.9; 95% CI 1.3, 2.8] patients in the intervention and control groups, respectively. In the intervention group, study physicians were responsible for 35.4% of all new prescriptions and for 15.6% of all drug terminations. Changes took place particularly in the prescription of CNS drugs. About 58% of the drugs initiated by study physicians were still in use 1 year later, and 25.5% of those terminated by study physicians had been reintroduced. Conclusion: Drug intervention as part of a CGA can be used to rationalize the drug therapy of a patient. However, its effectiveness is subsequently partly counteracted by other physicians working in the healthcare system.