Associations Between Drug Burden Index and Falls in Older People in Residential Aged Care

OBJECTIVES: To evaluate the association between the Drug Burden Index (DBI), a measure of a person's total exposure to anticholinergic and sedative medications that includes principles of dose-response and maximal effect and is associated with impaired physical function in community-dwelling older people, and falls in residents of residential aged care facilities (RACFs). DESIGN: Data were drawn from participants in a randomized controlled trial that investigated falls and fractures. SETTING: RACFs in Sydney, Australia. PARTICIPANTS: Study participants (N=602; 70.9% female) were recruited from 51 RACFs. Mean age was 85.7 ± 6.4, and mean DBI was 0.60 ± 0.66. MEASUREMENTS: Medication history was obtained on each participant. Drugs were classified as anticholinergic or sedative and a DBI was calculated. Falls were measured over a 12-month period. Comorbidity, cognitive impairment (Mini-Mental State Examination) and depression (Geriatric Depression Scale) were determined. RESULTS: There were 998 falls in 330 individuals during a follow-up period of 574.2 person-years, equating to an average rate of 1.74 falls per person-year. The univariate negative binomial regression model for falls showed incidence rate ratios of 1.69 (95% confidence interval (CI)=1.22-2.34) for low DBI ( Language: en