Adverse Effects of Anticholinergic Drugs on Cognition and Mobility: Cutoff for Impairment in a Cross-Sectional Study in Young–Old and Old–Old Adults
Résumé
Background: Drugs with anticholinergic properties are commonly prescribed in older adults despite growing evidence of their adverse outcomes. Several issues regarding these detrimental effects remain unresolved, such as the putative existence of a threshold above which anticholinergic drug consumption impairs cognitive or mobility performance.
Objectives: We aimed to investigate the number of anticholinergic drugs and the anticholinergic burden that leads to mobility or cognitive impairment and compare the effects in community-dwelling older adults in two age groups ("young-old" 55-74 vs. "old-old" ≥ 75 years).
Methods: In a cross-sectional study, we identified drugs with anticholinergic (antimuscarinic) properties using the Anticholinergic Drug Scale. Cognition was assessed using the Mini Mental State Examination (MMSE) and the Trail Making Test (TMT-A and TMT-B), and mobility was assessed using the Timed Up and Go (TUG) test.
Results: The study population consisted of 177 volunteers, 114 of whom were classed as young-old and 63 were classed as old-old adults. Despite the lack of cutoff values for impaired outcomes in young-old adults, impaired MMSE were significantly more numerous in users than in nonusers of anticholinergic drugs. In old-old adults, receiver operating characteristic (ROC) curve analysis indicated that taking a single anticholinergic drug per day was associated with impaired TMT-B completion time, TMT difference score (B-A), and TUG scores. The cutoff for anticholinergic burden was also one for these same outcomes. Based on these cutoff values, multivariate logistic regressions in old-old adults showed that the increased risk of impaired cognition and mobility was independent of confounding factors, including comorbidities. They also suggested that anticholinergic drugs would affect mobility through executive functions.
Conclusions: Drugs with anticholinergic (antimuscarinic) properties are associated with cognitive impairment in individuals as young as 55 years, and only one such drug per day, regardless of its anticholinergic burden, is associated with both impaired cognition and impaired mobility in old-old adults. Therefore, wherever possible, clinicians should avoid prescribing drugs with anticholinergic properties.