The Impact of Cognitive Dysfunction on Locomotor Rehabilitation Potential in Multiple Sclerosis.

Background: Cognitive dysfunction is a frequent manifestation of multiple sclerosis (MS) but its effect on locomotor rehabilitation is unknown. Objective: To study the impact of cognitive impairment on locomotor rehabilitation outcome in people with MS. Methods: We performed a retrospective analysis involving ambulatory patients with MS who were admitted for intensive, inpatient, multidisciplinary rehabilitation at the National Multiple Sclerosis Center of Melsbroek between the years 2012 and 2017. The Brief Repeatable Battery of Neuropsychological Tests (BRB-N) was used to determine the cognitive status of subjects as either impaired (COG-) or preserved (COG+). Locomotor outcome was compared between groups with the difference in 6-minute walk test (6MWT) measured at admission and discharge (Delta 6MWT). In addition, individual test scores of the BRB-N for attention (Paced Auditory Serial Addition Test 2" and 3"), visuospatial learning/memory (7/24 Spatial Recall Test), verbal learning/memory (Selective Reminding Test) and verbal fluency (Controlled Oral Word Association Test) were correlated to the Delta 6MWT. Results: A total of 318 complete and unique records were identified. Both groups showed a significant within-group Delta 6MWT during hospitalization (COG+: 47.51 m; COG-: 40.97 m; P < .01). In contrast, Delta 6MWT values were comparable between groups. The odds of achieving a minimal clinical important difference on the 6MWT did not differ significantly between both groups. Only attention/concentration was significantly correlated with Delta 6MWT (r = 0.16, P = .013). Conclusion: Cognitive impairment based on BRB-N results appears not to impede locomotor rehabilitation in ambulatory patients with MS. Attentional deficits are correlated to the extent of locomotor rehabilitation, suggesting the presence of a subtle effect of cognition.