Prediction of functional status from neuropsychological tests in community-dwelling elderly individuals.

Age-related dysfunction of frontal systems can result in deficits in planning, organization, self-control, and awareness of problems, which are likely to affect the ability to care for one's self. The purpose of this study was to determine the relationship between age-related frontal/executive deficits and impairment in instrumental activities of daily living (IADLs) in elderly individuals. Twenty-seven community-dwelling individuals were administered a comprehensive battery of neuropsychological tests and a performance-based evaluation of IADLs. Multiple regression analyses indicated that executive function and depression severity accounted for a significant proportion of variance in IADLs, with executive function making the greatest contribution. Tests measuring other cognitive functions, such as memory, language, and spatial skills, did not contribute significantly to the prediction of functional status. Furthermore, executive measures accounted for more variance than other demographic characteristics such as general health status, age, and educational level. The results of this study indicate that executive dysfunction in normal aging may be the best predictor of functional decline. A better understanding of the mechanisms that underlie IADL skills will ultimately aid in the development of compensatory and intervention strategies designed to delay the onset of assisted living and nursing home placement.

The ability of the Dementia Rating Scale to predict everyday functioning.

The Dementia Rating Scale (DRS) is a brief neuropsychological assessment battery designed to assess five areas of cognitive functioning in the elderly. The relationship between DRS performance and everyday functioning was examined for 50 psychogeriatric patients. Everyday functioning was assessed with a standardized performance measure examining self-care, safety, money management, cooking, medication administration, and community utilization. Regression analyses were conducted for each of the six functional domains. In addition, correlations between the DRS subscales and the functional areas were computed. Results revealed significant predictive relationships (p <.01) between performance on the DRS and most functional domains. The multiple Rs ranged from .52 - .70, accounting for 27% to 49% of the variance. The Initiation/Perseveration subscale was most heavily weighted in each analysis. Significant correlations were obtained between subdomains of cognition and most functional areas. The findings provide evidence of relationships between DRS performance and functional ability.