Cognition in Older Patients With Multiple Sclerosis Compared to Patients With Amnestic Mild Cognitive Impairment and Healthy Older Adults

Objective: Progress in the treatment of multiple sclerosis (MS) has resulted in larger numbers of patients living to an advanced age, but little is known about the cognitive status of these individuals. The primary purpose of this study was to identify differences in the cognitive performance between elderly individuals with MS and those with amnestic mild cognitive impairment (aMCI). Method: Three groups ranging in age from 60 to 80 were compared: patients with MS (n = 64), patients with aMCI (n = 58). and healthy adults (n = 70). All participants completed a standard neuropsychological test battery that evaluated domains of attention, processing speed, executive function, memory, language, and visual spatial function. Results: Compared to age- and gender-matched healthy controls, elderly MS patients exhibited a pattern of cognitive impairment centering on information processing speed and memory that was consistent with the deficits observed in other studies of MS patients regardless of age. Compared to aMCI patients. the MS patients exhibited worse performance on measures of processing speed, but better performance on a measure of memory under cued conditions (Selective Reminding Test), a nonspeeded measure of language (Boston Naming Test), and measures of executive function with processing speed statistically controlled (Trail Making Test, Stroop Test). Conclusions: Differences on neuropsychological measures can serve to distinguish aMCI from MS-related cognitive impairment in older patients, but it is essential that these measures control for the deficit in processing speed that is such a primary feature of MS.