Executive cognitive abilities and functional status among community-dwelling older persons in the San Luis Valley Health and Aging Study.

Abstract

The purpose of this study was to evaluate the contribution of the executive cognitive functions to self-reported and observed performance of activities of daily living and instrumental activities of daily living. These data were collected as part of a cross-sectional survey of community-dwelling older persons, using statistical sampling, in a two-county area of southern Colorado. Participants were interviewed and administered measures of general cognition, depression, executive functioning, and performance of self-care and instrumental activities, either in their homes or at the study clinic. A total of 1158 community-dwelling persons between the ages of 60 and 99 participated. Of these, 657 were female, 501 were male, 637 were Hispanic, and 521 were non-Hispanic whites. Subjects were administered the Mini-Mental State Exam (MMSE), a measure of executive functioning (the Behavioral Dyscontrol Scale), the Center for Epidemiologic Studies Depression scale (CES-D), and the Structured Assessment of Independent Living Skills (SAILS, a measure of observed performance of daily tasks). They also were interviewed regarding their reported ADL and IADL status using measures from the Longitudinal Study on Aging. Both general mental status and executive functioning demonstrated statistically significant univariate associations with all seven functional status measures (both self-report and observed performance). In a series of ordinary least squares regression models, executive functioning was a predictor for self-reported ADLs and observed performance of complex IADL tasks such as managing money and medications. Mental status did not predict self-reported functioning but was a predictor of observed performance. Depression was a significant variable for self-report measures but not for observed performance. Executive functioning and general mental status demonstrated some degree of independence from one another. Executive functioning is an important determinant of functional status for both self-reported and observed ADLs and IADLs and should be assessed routinely when evaluating the mental status and functional abilities of older people. These results replicate and extend previous research on executive functioning among older persons by examining these factors in a large bi-ethnic community sample.