Prevalence and Preventability of Adverse Medicine Events in a Sample of Australian Aged-Care Residents: A Secondary Analysis of Data from the ReMInDAR Trial

Background: Aged care residents are vulnerable to the harmful effects of medicines; however, data on the prevalence and preventability of adverse medicine events in aged care residents are scarce.

Aim: To determine the prevalence and preventability of adverse medicine events in Australian aged care residents.

Methods: A secondary analysis of data from the Reducing Medicine-Induced Deterioration and Adverse Reactions (ReMInDAR) trial was conducted. Potential adverse medicine events were identified and independently screened by two research pharmacists to produce a short-list of potential adverse medicine events. An expert clinical panel reviewed each potential adverse medicine to determine the likelihood that the event was medicine related (based on the Naranjo Probability Scale criteria). The clinical panel assessed preventability of medicine-related events using Schumock-Thornton criteria.

Results: There were 583 adverse events due to medicines, involving 154 residents (62% of the 248 study participants). There was a median of three medication-related adverse events (interquartile range [IQR] 1-5) per resident over the 12-month follow-up period. The most common medication-related adverse events were falls (56%), bleeding (18%) and bruising (9%). There were 482 (83%) medication-related adverse events that were preventable, most commonly falls (66% of preventable adverse medicine events), bleeding (12%) and dizziness (8%). Of the 248 residents, 133 (54% of the cohort) had at least one preventable adverse medicine event, with a median of 2 (IQR 1-4) preventable adverse medicine events per resident.

Conclusion: In total, 62% of aged care residents in our study had an adverse medicine event and 54% had a preventable adverse medicine event in a 12-month period.