Impact of Australian home medicines reviews on continuous polypharmacy and associated costs among older women: a cohort study.

Abstract

Introduction: Medication misadventure is associated with the use of polypharmacy and is highly prevalent in the older population living in the community, especially among women.

Aim: This study aimed to determine the impact of Home Medicines Reviews (HMRs) on continuous polypharmacy, the prevalence of continuous polypharmacy, and inflation-adjusted differences in costs among women who did and did not receive HMRs.

Method: The study included 9347 participants from the Australian Longitudinal Study on Women's Health who fulfilled the eligibility criteria from 77-82 years in 2003 to 91-96 years in 2017. Generalised estimating equations were used to estimate the association between HMRs and continuous polypharmacy. Out-of-pocket costs and benefits paid to government were presented as median costs for each participant from 2003 to 2017, alongside interquartile ranges.

Results: Only a small percentage of women received HMRs in 2003 (1.14%) but this percentage increased over time to 2017 (3.95%). The prevalence of continuous polypharmacy in 2017 was 39.06% amongst women who received an HMR and 28.05% amongst women who did not receive an HMR. There was evidence for an association between the use of HMRs and continuous polypharmacy in the following calendar year (OR 1.12; 95% CI 1.03, 1.21). There was an increase in out-of-pocket (OOP) medication costs in both women with and without HMRs, with the HMR group demonstrating higher OOP medication costs (AUD$26 to AUD$57) than the non-HMR group (AUD$22 to AUD$50).

Conclusion: HMRs were associated with a modest increase in the odds of continuous polypharmacy in the subsequent year. Increase in OOP medication costs over time highlights the need to further optimise cost-effective medications for individuals.