Analysis of Anticholinergic Medicine Effect on Cognitive and Functional Decline Among Older Adults

Abstract

The association between the long-term effect of anticholinergics and cognitive-functional decline in older adults is not clear. If such an association exists, it would be important to account for the anticholinergic burden whenever we evaluate the risk factors of cognitive-functional decline in older adults. Adopting an efficient and practical method to assess anticholinergic burden is crucial in estimating such an association. Thus, this study had two objectives: (1) to validate an assessment approach in quantifying anticholinergic burden; and (2) to evaluate the impact of the anticholinergic burden on the cognitive-functional decline in older adults.

The study used data from the S. AGES (Sujets Ages, elderly subjects) sub-cohort and included 983 community older adults aged 64-97 years old, followed up between 2009 and 2013. The Anticholinergic and Sedative Burden Catalog (ACSBC), a recently developed anticholinergic catalogue, and the Anticholinergic Cognitive Burden Scale (ACB), an old validated practical scale, were used to calculate the average daily anticholinergic burden scores throughout the follow-up period. Mini Mental State Examination (MMSE), Instrumental Activities of Daily Living (IADLs), and Activities of Daily Living (ADLs) measured at the time of inclusion month (M0) and every 12 months (M12, M24, and M36) were used to evaluate cognitive and functional decline. The study also combined the MMSE with BADLs, the MMSE with IADLs, and the MMSE with ADLs (BADLs & IADLs) to create three integrated cognitive-functional subscales.

The first step was to check the external nomological validity by estimating the level of correlation between the average daily ACSBC and ACB scores. Then, the analysis regressed the two average daily anticholinergic burden scores (ACSBC and ACB) in mixed models over time with cognitive and functional outcomes and compared their adjusted β estimates. The second step of the analysis focused on modeling each cognitive-functional decline combined subscale with the average daily anticholinergic burden scores (ACSBC and ACB).

The study showed that quantifying anticholinergic burden using a scale or a catalogue provided parallel results across the mixed models. Additionally, results showed that the average daily anticholinergic burden is associated with cognitive and functional decline, particularly when both outcomes are combined, reflecting the nature of aging that is accompanied by concurrent decline in cognitive and functional activities.

Results from this study serve the community and help geriatricians to manage the pharmacotherapy regimen provided to older persons while possibly lowering the expense of their treatment due to unintended side effects. In addition, the results of this study provide additional evidence to account for the anticholinergic burden when assessing the risks of cognitive-functional decline.