Background To date, it remains unclear to what extent cognitive competence is related to a change in general functional status in older adults. Objectives To evaluate both the cross-sectional and the longitudinal relation between cognitive functioning and functional status. Methods Sensorimotor speed, memory, and executive functioning were assessed in a large population of healthy adults aged 60 years and older (n = 485) who participated in the Maastricht Aging Study. Data from the baseline (1993-1995), three-year follow-up, and six-year follow-up were used. Functional status was measured using the SF-36, which was coded into a physical and a mental component summary measure. Results After adjustment for age, sex, and educational level, a high level of cognitive functioning appeared to be associated with better functional status in the cross-sectional analysis. Longitudinal analyses demonstrated, that cognitive functioning was not a predictor of functional status three or six years later. Conclusions Thus while cognitive functioning is useful clinically for predicting the short-term functional status of an older person, it is not useful for predicting that person's long-term (> 3 years) functional status and thus the period of validity of the results of these tests in answering such questions is limited.
van Hooren, S. A. H., van Boxtel, M. P. J., Valentijn, A. M., Bosma, J. H. A., Ponds, R. W. H. M., & Jolles, J. (2005). Influence of cognitive functioning on functional status in an older population: 3- and 6-year follow-up of the Maastricht Aging Study. International Journal of Geriatric Psychiatry, 20, 883-888. https://doi.org/10.1002/gps.1373