Racial and Sex Differences in Associations Between Activities of Daily Living and Cognition in Community-Dwelling Older Adults

ObjectivesTo examine the association between function measured according to activities of daily living (ADLs), instrumental activ1ities of daily living (IADLs), and cognition assessed according to Mini-Mental State Examination (MMSE) scores of older African-American and non-Hispanic white community-dwelling men and women. DesignCross-sectional study assessing associations between self-reported ADL and IADL difficulty and MMSE scores for race- and sex-specific groups. SettingHomes of community-dwelling older adults. ParticipantsA random sample of 974 African-American and non-Hispanic white Medicare beneficiaries aged 65 and older living in west-central Alabama and participating in the University of Alabama at Birmingham Study of Aging, excluding those with reported diagnoses of dementia or with missing data. MeasurementsFunction, based on self-reported difficulty in performing ADLs and IADLs, and cognition, using the MMSE. Multivariable linear regression models were used to test the association between function and cognition in race- and sex-specific groups after adjusting for covariates. ResultsMini-Mental State Examination scores were modestly correlated with ADL and IADL difficulty in all four race- and sex-specific groups, with Pearson correlation coefficients ranging from -0.189 for non-Hispanic white women to -0.429 for African-American men. Correlations between MMSE and ADL or IADL difficulty in any of the race- and sex-specific groups were no longer significant after controlling for sociodemographic factors and comorbidities. ConclusionMini-Mental State Examination was not significantly associated with functional difficulty in older African-American and non-Hispanic white men and women after adjusting for sociodemographic factors and comorbidities, suggesting a mediating role in the relationship between cognition and function.