Randomized controlled trial of physical activity intervention effects on fatigue and depression in multiple sclerosis: Secondary analysis of data from persons with elevated symptom status

Background: Physical activity interventions have yielded reductions in fatigue and depressive symptoms among persons with multiple sclerosis(MS) who have not been screened for elevated baseline symptoms scores. Purpose: This short communication describes a secondary analysis of data from a previous randomized controlled trial (RCT) and focused on physical activity intervention effects on fatigue and depression among persons with MS who had elevated baseline symptom scores. Method: Of the 76 persons who completed the RCT, 64(84%) had baseline fatigue severity scale(FSS) scores indicating elevated levels of fatigue(n = 30,intervention; n = 34,control), and 26(34%) had baseline hospital anxiety and depression scale, depression(HADS-D) scores indicating elevated depressive symptoms (n = 13, intervention; n = 13,control). The physical activity intervention was delivered over a 6-month period, and the control condition was a 6-month waitlist. The participants completed the FSS and HADS-D as part of baseline and follow-up battery of assessments. Results: There was a statistically significant change in FSS scores favoring the physical activity intervention, and the effect size of 0.73 was larger than reported in a previous meta-analysis of RCTs of physical activity and fatigue in MS of 0.45(95%CI = 22,.68). We observed a statistically significant change in HADS-D scores favoring the physical activity intervention, and the effect size of 1.21 was larger than reported in a previous meta-analysis of RCTs of physical activity and depression in MS of 0.36(95%CI = 18,.54). Conclusion: Such results provide preliminarily support for the application of physical activity interventions for the "treatment" of fatigue and/or depression in MS, pending subsequent confirmatory efficacy or effectiveness trials.