Background: Alexithymia, meaning no words for emotions is a common problem that could affect up to 53% of patients in multiple sclerosis (MS).

Objective: To determine the frequency of alexithymia in MS and investigate MS-related abnormalities in structural magnetic resonance imaging (MRI) and their associations with fatigue and cognitive functions.

Methods: Ninety-five patients at all stages of the disease were examined: 21 with clinically isolated syndromes (CIS), 30 with relapsing-remitting MS (RRMS), 21 with primary (PP) and 23 with secondary progressive MS (SPMS). Alexithymia was measured with the Toronto alexithymia scale (TAS-20) and correlated to cognitive functions, depression, and fatigue. Voxel-based morphometry MRI was analyzed to determine lesion load, cerebral and regional atrophy.

Results: Fifty-seven of patients had alexithymia with no significant difference between the clinical phenotypes. Alexithymic patients differed from non-alexithymic patients on fatigue, depression and information processing speed. Compared to non-alexithymic patients, alexithymic patients had decreased volumes of cerebral and cerebellar white matter and there was a significant relationship between alexithymia and decreased brainstem, thalamic and corpus callosum volume.

Conclusions: Regardless of the phenotype of MS, alexithymia is associated with atrophy of cerebral and cerebellar white matter, brainstem, corpus callosum, and thalami.