Dual-task cost in people with multiple sclerosis: A case–control study

Abstract

Introduction Limitations in fine motor functioning and cognitive performance are frequently reported in multiple sclerosis. Studies about dual-task costs in multiple sclerosis generally explore walking and postural performance. This study aims at exploring dual-task costs when simultaneously performing fine motor and cognitive tasks. Method Eighty people with multiple sclerosis and 80 matched controls performed the nine-hole peg test and the months backward test under single and dual-task conditions. Differences in performance over time were analysed with the paired t-test; differences in dual-task costs between groups were analysed with independent t-tests. Results People with multiple sclerosis and controls showed a significant decrease in fine motor and cognitive performance in dual-task conditions compared to single-task conditions ( P < 0.01). People with multiple sclerosis with limited hand capacity showed larger dual-task costs for cognitive performance compared to other hand capacity groups ( P < 0.05). Individuals with multiple sclerosis with lower cognitive capacity showed larger dual-task costs for fine motor performance ( P < 0.01). Conclusion Both people with multiple sclerosis and controls experience dual-task costs. People with multiple sclerosis with limited hand function showed an increased dual-task cost of cognitive performance and individuals with limited cognitive capacity showed a higher dual-task cost for fine motor performance. Therefore, occupational therapists should focus on cognitive or fine motor aspects during dual-task training dependent on individuals' capacities.