OBJECTIVES : Anticholinergic drug (ACH) use is linked with cognitive dysfunction and is often considered to be potentially inappropriate in older adults. Health disparities in cognitive status with ACH use may exist. We aim to evaluate the association between ACH use and cognitive impairment and the effect of disparity parameters (gender, race, income, education, and rural or urban areas) on this relationship.

METHODS : The analyses included 13,623 black and white US adults aged ≥65 years from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study (recruited 2003-2007). The ACH use was defined by the 2015 Beers Criteria and cognitive impairment was measured by the Six-Item Cognitive Screener. Multivariable logistic regression models assessed disparities in cognitive impairment with ACH use, iteratively adjusting for disparity parameters and other covariates. The full models included interaction terms between ACH use and other covariates. A similar approach was used for class specific ACH exposure and cognitive impairment analyses.

RESULTS : Approximately 14% of the participants used at least one ACH listed in the Beers criteria. Antidepressants were the most frequently prescribed ACH class. A significant gender-race interaction illustrated that females compared with males (in blacks: odds ratio [OR]=1.28, 95% CI 1.10–1.49 and in whites: OR=1.96, 95% CI 1.74–2.20), and especially white females (black vs. white females: OR=0.71, 95% CI 0.64–0.80) were more likely to receive ACHs. Higher odds of cognitive impairment were observed among ACH users compared with the non-users (OR=1.27, 95% CI 1.01–1.59). Our class level analyses illustrated that only antidepressant users (OR=1.44, 95% CI 1.01–2.04) showed significant association with cognitive impairment in the fully adjusted model.

CONCLUSIONS : We observed demographic and socioeconomic disparities in ACH use and in cognitive impairment, individually. Further research is needed to better understand the contributing factors of such differences to develop appropriate interventions.