Improvement in prescriptions while maintaining overall health outcomes: a prospective observational study conducted in Japanese facilities for older people

BACKGROUND: Improvements in the use of polypharmacy or potentially inappropriate medication (PIM) may reduce medication costs in Japan. We aimed to evaluate the impact of improvement in prescription on both overall health outcomes and medication costs in Japanese facilities for older people. METHODS: Residents in Japanese facilities for older people between March 2019 and March 2020 were included in this study. The following five indices were used to evaluate overall health outcomes: EuroQoL-5D-5L, Barthel Index, Mini Mental State Examination, Dementia Behaviour Disturbance Scale, and Vitality Index. The team, which consisted of one physician and several pharmacists, suggested improved prescriptions for the attending physicians of the participants. The impact of improvement in prescriptions on the health outcomes score, medication costs, and the number of medications were evaluated through two comparison groups: those whose number of medications decreased (decrement group, DG) and those whose medications did not (not decrement group, NDG); those prescribed PIMs in March 2019 and those not prescribed PIMs in March 2020 (improvement group, IG) and those prescribed PIMs both in March 2019 and March 2020 (not improvement group, NIG). In both comparison groups, propensity score matching was performed to balance demographics, and all health outcome scores, medication costs, and the number of medications in March 2020 were assessed using a t-test. Statistical significance was set at a p-value of < 0.05. RESULTS: Eight-hundred-and-ninety-one participants (75.5% women, 86.2 ± 7.9 years old) were enrolled. After matching, in the comparison between the DG (N = 232, 77.2%, 85.7 ± 8.5) and NDG (N = 232, 78.5%, 86.0 ± 3.1), changes in the health outcomes score were nonsignificant. However, the medication costs and the number of medications significantly decreased. After matching, in the comparison between IG (N = 141, 75.2%, 86.7 ± 8.1) and NIG (N = 273, 74.2%, 86.2 ± 8.3), changes in health outcome scores and medication costs were not significant. However, the number of medications significantly decreased. CONCLUSIONS: Improvements in prescriptions did not adversely affect the overall health outcomes. However, it impacted medication costs and the number of medications. Improvement in prescriptions could decrease medication costs while maintaining overall health outcomes.