Tract-specific white matter correlates of fatigue and cognitive impairment in benign multiple sclerosis

J Neurol Sci. 2013 Jul 15;330(1-2):61-6. doi: 10.1016/j.jns.2013.04.005. Epub 2013 May 1.


Background: Although benign multiple sclerosis (BMS) is traditionally defined by the presence of mild motor involvement decades after disease onset, symptoms of fatigue and cognitive impairment are very common.

Objective: To investigate the association between micro-structural damage in the anterior thalamic (AT) tracts and in the corpus callosum (CC), as measured by diffusion tensor imaging (DTI) tractography, and fatigue and cognitive deficits.

Methods: DTI data were acquired from 26 BMS patients and 24 sex- and age-matched healthy controls.

Results: General and mental fatigue scores were significantly impaired in patients compared with controls (p≤0.05 for both) and 38% of patients resulted cognitively impaired. Mean diffusivity (MD) of the AT and CC tracts was significantly higher and fractional anisotropy (FA) was lower in patients compared with controls (p<0.001 for all). Fatigue was associated with increased MD (p=0.01) of the AT tracts whereas deficit of executive functions and verbal learning were associated with decreased FA in the body (p=0.004) and genu (p=0.008) of the CC. Deficits in processing speed and attention were associated with the T2 lesion volume of the AT tracts (p<0.01 for all).

Discussion: These findings suggest that fatigue and cognitive impairment are quite frequent in BMS patients and are, at least in part, related to micro-structural damage and T2LV of WM tracts connecting the brain cortical and sub-cortical regions of the two hemispheres.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Aged
  • Anisotropy
  • Behavior / physiology
  • Brain / pathology
  • Brain Mapping
  • Cognition Disorders / etiology
  • Cognition Disorders / pathology*
  • Cognition Disorders / psychology*
  • Corpus Callosum / pathology
  • Diffusion Tensor Imaging
  • Executive Function / physiology
  • Fatigue / etiology
  • Fatigue / pathology*
  • Fatigue / psychology*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Multiple Sclerosis / complications
  • Multiple Sclerosis / pathology*
  • Multiple Sclerosis / psychology*
  • Neural Pathways / pathology*
  • Neuropsychological Tests
  • Prospective Studies
  • Spinothalamic Tracts / parasitology
  • Verbal Learning / physiology