The Changing Pattern of Anticholinergic Prescribing in a Low- to Middle-income Country: Comparison of Two Datasets

Background: While the effects of anticholinergic drug use have been increasingly highlighted, the trends and patterns of anticholinergic drug use are, however, less well understood. Aim: To determine the changes in frequency and pattern of anticholinergic drug use within a low- to middle-income country. Method: Comparisons were made between two datasets obtained in 2013-15 and 2020-22 from population-based surveys conducted among Malaysian residents aged 55 years and older. Anticholinergic exposure was determined using the anticholinergic cognitive burden (ACB) tool. The frequency of prescriptions were reported by the Anatomical Therapeutic Classification (ATC) groups. Results: Medication data were available in 1616 and 2733 participants from 2013-15 and 2020-22 respectively, of whom 293 (18.1%) and 280 (10.2%) participants were on at least one medication with ACB score ≥ 1. Within ATC classes, cardiovascular medications were the most commonly prescribed in both surveys but had reduced over time. The use of nervous system medications had increased, in the increase seen in antipsychotic prescribing. The prescription of medications within the alimentary and respiratory classes had reduced. Multivariate analyses found that those interviewed in 2020-22 had significantly less likely than those in 2013-15 to have total ACB score=1-2 (odds ratio [95% confidence interval] = 0.473[0.385-0.581]) and ACB ≥ 3 (0.251[0.137-0.4600]) compared to ACB=0 after adjustment for potential confounders. Conclusion: A reduction in anticholinergic exposure was observed over time. However, more types of medications with anticholinergic effects were prescribed with an increase in the prescription of nervous system medications. The increase in antipsychotic use, in particular, is of concern and deserves further evaluation.