According to a new preprint study, published in medRxiv.org, there appears to be a robust link between subjective fatigue and depression in early relapsing-remitting multiple sclerosis (RRMS).

The study included participants from FutureMS, a national cohort of patients with newly diagnosed RRMS in Scotland. The study participants were assessed based on an array of clinical measures and structural brain MRI data. The validated Fatigue Severity Scale was used to evaluate subjective fatigue.

Investigators included data from 322 participants at baseline, when 49.5% of the cohort had clinically significant fatigue. Bivariate correlations revealed that fatigue severity had a significant correlation with all included measures of physical disability, affective disturbance, cognitive performance, and sleep quality. However, it did not correspond with structural brain imaging variables, such as normalized lesion and gray matter volumes. Fatigue had strong correlations with depression, followed by Expanded Disability Status Scale in the network analysis. Weak links were noted with walking speed, subjective sleep quality, and anxiety. On separately accounting for measurement of tiredness in the evaluation of depression, certain important depressive symptoms, such as anhedonia, subjective concentration deficits, subjective alteration in speed of movement, and appetite, were still associated with fatigue… (Medscape)