The Intersection Of Cognitive Performance, Physical Function, Aging, And Multiple Sclerosis: A Cross-sectional Comparative Study

Abstract

PURPOSE: Older adults with MS have worse physical and cognitive function than older adults without MS and young and middle-aged adults with MS. To date, there is no evidence regarding the associations, or coupling, of cognitive and physical function outcomes in older adults with MS. The purpose of this study was to examine the associations between physical (i.e., walking speed and endurance and functional mobility) and cognitive (i.e., information processing speed and verbal memory) functions in older adults with multiple sclerosis (MS) and healthy controls. METHODS: 40 older adults with MS and 40 demographically-matched controls undertook measures of physical and cognitive function. Bivariate linear relationships were examined with Pearson correlations in the overall sample and subsamples of older adults with MS and healthy controls. Linear regression analyses were further used to examine the independent associations between demographic characteristics and physical and cognitive function variables in the subsamples. RESULTS: Cognitive function (i.e., information processing speed) was significantly correlated with all physical function variables in the overall sample, and these correlations were driven by the subsample of older adults with MS. The linear regression analyses further indicated that information processing speed and years of education consistently explained variance in all physical function variables, beyond the influence of demographic variables, in older adults with MS. CONCLUSIONS: Information processing speed and physical function are strongly correlated in older adults with MS. Future research should examine underlying neurobehavioral mechanisms associated with cognitive and physical function and behavioral strategies for jointly improving these functions in older adults with MS.