Heterogeneity of cognitive and motor impairments in multiple sclerosis: A study with the MSFC

Abstract

Heterogeneous neuropsychological manifestations of multiple sclerosis (MS) difficult identification of patients with cognitive impairments. Cluster analyses were used to discriminate between groups of 40 MS patients and 48 demographically comparable control participants, using the three instruments of the Multiple Sclerosis Functional Composite Measure (MSFC): PASAT (cognition), Nine Hole Peg Test (manual dexterity), and Time to Walk 25 Feet. Four clusters resulted. In the first one were classified only noncompromised participants. The fourth cluster was composed by patients with major cognitive and motor impairments. Both patients and controls were found in two intermediate groups, one characterized by minor and the other by moderate lower cognitive performance. Significant diffences between clusters were found with ANOVA. Cognitive performance covaried with age and formal schooling. Most MS patients could not be accurately distinguished from controls, but one group was characterized by both cognitive and motor impairmens, which may dissociate at initial stages of disease. Keywords: Multiple sclerosis; cognition; neuropsychology; MSFC; cluster analysis.