Impact of medication reconciliation and medication reviews on the incidence of preventable adverse drug reactions during hospitalization of elderly patients. A randomized controlled trial.

Background: Of all adverse drug reactions, 35-45% are due to medication errors and would therefore be preventable. Thus, it is essential to implement effective strategies to prevent medication errors. However, it remains unclear whether medication reviews provide an additional benefit compared to medication reconciliation regarding medication safety. Aim: The present study aimed to evaluate whether medication reconciliation and medication reviews affect the incidence of preventable adverse drug reactions in elderly patients. Method: Non-elective patients 65 years and above admitted to the hospital, taking at least one high-risk drug, were eligible for participation in a three-armed randomized controlled trial. One group went through the medication reconciliation process, a second group received a comprehensive medication review, including medication reconciliation, and the third group did not receive any pharmaceutical intervention (control group). The incidence of preventable adverse drug reactions during hospitalization was set as the primary endpoint. The severity of the preventable adverse drug reactions and the number and clinical relevance of drug-related problems and discrepancies were defined as secondary endpoints. Results: In 207 patients, 74 preventable adverse drug reactions were detected. Neither medication reconciliation nor medication reviews showed a significant impact on the incidence of preventable adverse drug reactions compared to the control group. However, medication reviews significantly reduced the severity of preventable adverse drug reactions (p=0.017). Conclusion: The current study results suggest that medication reviews may have an impact on a clinically relevant outcome by reducing the severity of preventable adverse drug reactions. A significant impact of medication reconciliation on clinically relevant outcomes could not be demonstrated. Based on the results of this study, when deciding on a pharmaceutical intervention comprehensive medication reviews should be preferred over sole medication reconciliation whenever possible.