Anticholinergic drug use and mortality among residents of long-term care facilities: a prospective cohort study

Abstract

Few studies have investigated the possible association between use of anticholinergic drugs and mortality. The objectives of this study were to investigate the prevalence and determinants of anticholinergic drug use and the possible association between anticholinergic drug use and mortality. Data were obtained from 53 long-term care wards in Helsinki, Finland, in 2003. Medication, diagnostic, and mortality data were available for 1004 residents. Each resident's anticholinergic load was calculated using the Anticholinergic Risk Scale (ARS). Cox proportional hazards models were used to investigate the risk of death among users with a mild anticholinergic load (ARS score 1-2) and high load (ARS score ≥3) compared with nonusers of anticholinergic drugs. Age, sex, and nutritional status were used as covariates. Among the 1004 residents, 455 (45%) were nonusers of anticholinergic drugs, 363 (36%) had a mild anticholinergic load, and 186 (19%) had a high anticholinergic load. One-year all-cause mortality rates were 28%, 29%, and 27%, respectively. Higher ARS scores were not associated with mortality (ARS score 1-2: hazard ratio 1.08; 95% confidence interval, 0.84-1.41; ARS score ≥3: hazard ratio 1.05; 95% confidence interval, 0.75-1.46). Anticholinergic drug use was common; however, high ARS scores were not associated with mortality. Further research is needed using alternative models and among different resident populations.