Subcortical atrophy and cognition: sex effects in multiple sclerosis

Area of Science:

• Neuroimaging and Neurology
• Neuroscience
• Medical Research

Background:

• Gray matter (GM) atrophy is a known characteristic of multiple sclerosis (MS), often associated with cognitive impairment.
• The precise relationship between subcortical GM atrophy and cognitive dysfunction in early MS requires further elucidation.

Purpose of the Study:

• To investigate the association between subcortical gray matter atrophy and cognitive function in patients with early relapsing-onset MS.
• To identify specific subcortical structures affected by MS and their correlation with cognitive performance.

Main Methods:

• Structural MRI and comprehensive neuropsychological evaluations were conducted on 120 early MS patients and 50 controls, 6 years postdiagnosis.
• Deep gray matter volumes were automatically segmented, and cognitive function was assessed across seven domains.
• Stepwise linear regression analysis was employed to predict average cognition within the patient cohort.

Main Results:

• Significant reductions in most deep GM volumes were observed in MS patients, with greater atrophy noted in men (-11%) compared to women (-6.3%).
• Cognitive functions were more profoundly affected in male MS patients, with all domains except visuospatial memory showing impairment.
• Thalamic volume, sex, and education level were identified as the strongest predictors of average cognitive performance in the MS group (adjusted R(2) = 0.31).

Conclusions:

• Six years after diagnosis, MS significantly impacts almost all subcortical structures, with a more pronounced effect in men.
• Cognitive deficits are more severe in male MS patients, highlighting sex-specific differences in disease progression.
• Thalamic volume, sex, and education are critical factors influencing cognitive outcomes in early MS, underscoring the importance of these subcortical structures and sex-specific considerations in MS-related cognitive decline.