Effects Of A Cooling Vest On Dual-task Performance And Fatigability In Persons With Multiple Sclerosis

Abstract

Fatigue and heat sensitivity are commonly reported symptoms in persons with multiple sclerosis (PwMS). PwMS also often have difficulty performing concurrent cognitive and motor tasks that presents as a dual-task decrement. Heat sensitivity along with a dual-task decrement may hinder activities of daily living and quality of life for PwMS. Though using a cooling vest could help decrease heat sensitivity, it is currently unknown if it improves dual-tasking performance in PwMS. PURPOSE: To examine the effects of a cooling vest on cognitive-motor dual-task cost (DTC) and fatigability in PwMS. METHODS: 5 PwMS participated in two sessions that were at least 1 week apart. During one session participants wore a sham cooling vest and the other session an actual cooling vest. During each session participants completed a Timed 25-Foot Walk Test (T25FWT), 6 Minute Walk Test (6MWT), T25FWT while performing Serial 3’s, and a 6MWT while narrating a story. The type of vest and order of tests was randomized for each participant. Total times for T25FWT and total distances for 6MWT were recorded. DTC, defined as the percent change between single- and dual-task performance, was calculated. Fatigability, defined as the difference between the averages of the first two and the last two lap times of the 6MWT, was calculated. Paired samples t-tests were used to compare DTC during cooling and non-cooling sessions and fatigability during single- and dual-task conditions within each session. RESULTS: The mean DTC during the 6MWT for cooling and non-cooling was -4.1% and -6.5%, respectively. The DTC during the T25FWT for cooling was 7.3% and 11.5% for non-cooling. The mean distance walked during 6MWT dual-task increased from 275.5m without cooling to 285.6m with cooling. There was a trend towards significant difference between single- and dual-task fatigability during 6MWT for non-cooling session (Single: 1.6±7.6m; Dual: 6.2±5.3m; p=.051), but not for cooling session (Single: 0.7±3.8m; Dual: 12±16.4m; p=.082). CONCLUSION: Preliminary results with lower DTC and no significant difference between single- and dual-task fatigability when using a cooling vest suggests that a cooling vest may have a benefit PwMS while dual-tasking during endurance activities. Further research with a larger sample size is needed to confirm these findings.