Effect of number of medications on the risk of falls among community-dwelling older adults: A 3-year follow-up of the SONIC study

Aim: This study examined the association between the number of prescribed medications and falls among community-dwelling older adults.Methods: We conducted a geriatric comprehensive health-checkup on community-dwelling adults aged 69-91 years who participated in the Septuagenarians, Octogenarians, and Nonagenarians Investigation with Centenarians study. The final analysis of this study included 1,076 participants with complete data. The participants were divided into four groups based on the number of medications at baseline: 0, 1, 2-4, and >= 5. At the 3-year follow-up, the participants were asked whether they had fallen in the past year. Multivariable logistic regression analysis was performed to assess the relationship between the number of medications taken and falls after adjusting for confounding factors.Results: The prevalence rates of falls were 10.5%, 18.2%, 18.3%, and 19.8% in the no-medication, one-medication, comedication, and polypharmacy groups, respectively. In the one-medication prescription group, 59% of prescriptions were for fall-risk-increasing drugs (FRID). Multivariable analysis showed a significantly higher incidence of falls in the one-medication group (adjusted odds ratio [OR], 1.91; 95% confidence interval [CI], 1.04-3.54), co-medication (OR, 1.89; 95% CI, 1.09-3.29), and polypharmacy groups (OR, 1.94; 95% CI, 1.09-3.45) than in the no-medication group.Conclusions: The study showed that polypharmacy, as well as just taking one medication, can affect the occurrence of falls. This suggests that in addition to the number of medications and polypharmacy, the type of medication, such as FRID, affects the risk of falls. Therefore, pharmacotherapy should consider the risk of falls in older adults when prescribing medications.