Anticholinergic medication use and falls in Australian residential aged care: a retrospective multisite cohort study

Abstract

Background: Associations between anticholinergic load and falls remain understudied in residential aged care facilities (RACFs). Aims: To examine associations between anticholinergic load and falls in the first year after entry to an RACF. Methods: We aggregated routinely collected data from 27 RACFs in New South Wales, Australia. Anticholinergic load and falls were repeatedly measured for one year after residents first entered an RACF. Thirteen 28-day review periods were set. Associations between anticholinergic load in a review period and any falls in the next review period were examined, comprising 12 repeated measurements of associations. We included new residents aged ≥ 65 years, who entered an RACF between 1 July 2014 and 2 September 2021. Six scales were used: Anticholinergic Cognitive Burden (ACB), Anticholinergic Drug Scale (ADS), Anticholinergic Loading Scale (ALS), Anticholinergic Risk Scale (ARS), Chew’s list, and Clinician-rated Anticholinergic Score (CrAS). We used mixed-effect logistic regression models, adjusting for potential confounders. Facility was used as a cluster variable. Results: For the 2300 residents (67.7% females), there were steady increases in mean anticholinergic load from the first to the 12th review period. Per one-point higher anticholinergic load was associated with an increased risk of falls, adjusted odds ratios: 1.08 (95% confidence interval[CI] 1.04, 1.12) using ACB, 1.11 (95%CI 1.06, 1.15) using ADS, 1.15 (95%CI 1.10, 1.21) using ALS, 1.10 (95%CI 1.04, 1.17) using ARS, 1.18 (95%CI 1.09, 1.27) using Chew’s list, and 1.14 (95%CI 1.10, 1.19) using CrAS. Conclusion: Anticholinergic scales may be useful to inform falls prevention programs for new RACF residents.