Benign multiple sclerosis: looking beyond physical disability.

Area of Science:

• Neurology
• Neuroimmunology
• Clinical Neuroscience

Background:

• Traditional classification of Benign Multiple Sclerosis (BMS) primarily uses the Expanded Disability Status Scale (EDSS).
• The underlying mechanisms and comprehensive characteristics of BMS remain incompletely understood.
• Previous research has not fully explored neuroimaging correlates and broader clinical parameters in BMS.

Purpose of the Study:

• To analyze the frequency of BMS when considering parameters beyond the EDSS.
• To investigate the neuroimaging correlates associated with BMS.
• To identify clinical and demographic predictors of BMS status.

Main Methods:

• BMS (EDSS ≤ 3.0 after 10 years) and traditional MS (EDSS > 3.0) cohorts were assessed for disability, fatigue, depression, and cognition.
• BMS patients were further stratified using stringent EDSS criteria (≤ 2.0 after 15 years) and as 'fully benign' (no fatigue, depression, or cognitive deficit).
• Lesion counts in four locations for dissemination in space (DIS) were quantified, and logistic regression analyzed predictors of BMS.

Main Results:

• Depression frequency was similar between traditional MS (n=23) and BMS (n=30) groups.
• 43.3% of BMS individuals exhibited no fatigue, depression, or cognitive deficit.
• Spinal cord lesion load was significantly lower in BMS patients compared to traditional MS (p=0.024); higher education (OR=0.839) and fewer spinal cord lesions (OR=1.364) predicted BMS status.

Conclusions:

• The EDSS-based classification of BMS shows comparable depression rates to traditional relapsing-remitting MS (RRMS), highlighting the need for a more inclusive BMS definition.
• Higher educational attainment and a reduced burden of spinal cord lesions are significantly associated with benign multiple sclerosis.
• These findings suggest that factors beyond physical disability, such as cognitive and emotional well-being, alongside specific neuroimaging markers, are crucial in defining BMS.