The Cognitive Reserve May Influence Fatigue after Rehabilitation in Progressive Multiple Sclerosis: A Secondary Analysis of the RAGTIME Trial

Cognitive reserve (CR) seems to be an ability to adapt cognitive processes in response to brain disease and may influence rehabilitation outcomes. This is a secondary analysis of the “Robot- Assisted Gait Training versus conventional therapy on mobility in severely disabled progressive MultiplE sclerosis patients” (RAGTIME) trial to investigate the influence of CR on the outcomes after gait rehabilitation in people with multiple sclerosis (PwMS).We included 53 PwMS and severe gait disability (EDSS 6–7). The participants were randomized into two groups to receive either robot-assisted gait training or overground walking (three times/week over four weeks). CR was evaluated by the Cognitive Reserve Index questionnaire (CRIq), which encompasses three sections (CRI Education, CRIWorking Activity, and CRI Leisure Time). We stratified the patients using the 115 cut-off CRIq total score of at least a medium-high CR. The outcome measures were Timed 25-Foot Walk, 6 min walking test, Berg Balance Scale, Multiple Sclerosis Impact Scale—29, Multiple Sclerosis Walking Scale—12, Patient Health Questionnaire—9, and Fatigue Severity Scale (FSS). After gait rehabilitation, the FSS was significantly improved in those patients with higher CR compared with the others (F = 4.757, p = 0.015). In our study, CR did not affect the gait, balance, disability perception, and depression. Conversely, it positively influenced the fatigue after gait rehabilitation.