Association between polypharmacy and the risk of requiring long‐term care among community‐dwelling older residents: A retrospective cohort study

Abstract

Abstract Background Polypharmacy has been increasing attention as it is associated with a number of health problems, especially adverse outcomes in older adults. However, there is insufficient evidence regarding the risk of polypharmacy and long‐term care. Methods We analyzed a community‐based retrospective cohort of residents of Goto City by combining data from health checkups, prescription information, and long‐term care needs certification database. The study sample included residents aged 65–79 years in 2015 who were followed up for 4 years. The number of medications used was categorized as 0, 1–5, 6–9, and ≥10. The outcome was initiation of long‐term care. Cox regression models were used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) adjusted for potential confounders. Results Among 1083 participants, 58 used long‐term care for 4 years. Compared with participants taking no medication, the incidence of long‐term care initiation was approximately double in those taking 1–5 medications, four times higher in people taking 6–9 medications, and 13 times higher in people taking ≥10 medications. After adjusting for potential baseline confounders, the number of medications was significantly associated with the initiation of long‐term care services (1–5 drugs: adjusted HR 2.38, 95% CI 1.06–5.34; 6–9 drugs: adjusted HR 2.97, 95% CI 1.23–7.15; and ≥10 drugs: adjusted HR 5.54, 95% CI 1.89–16.23). Conclusions Among community‐dwelling residents aged 65–79 years, the risk of requiring long‐term care had a dose–response relationship with the number of prescribed medications.

Keywords

• functional disability
• geriatrics
• long‐term care
• polypharmacy