Differential white and gray matter damage in highly active multiple sclerosis: A prospective cohort study

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• Multiple sclerosis (MS) is a chronic autoimmune disease affecting the central nervous system.
• Disease activity and progression vary significantly among MS patients.
• Identifying factors predicting rapid disease progression is crucial for effective management.

Purpose of the Study:

• To investigate and compare differential brain volume changes between highly active multiple sclerosis (HAMS) and non-HAMS patients.
• To analyze the rate of gray matter volume (GMV) and white matter volume (WMV) changes in HAMS vs. non-HAMS cohorts.
• To determine if brain volume changes correlate with disease activity markers over a 24-month period.

Main Methods:

• Retrospective analysis of 64 MS patients, classifying them as HAMS or non-HAMS based on relapse rates and lesion load.
• Acquisition of high-resolution T1-weighted MRI scans at disease onset and annually for two years.
• Utilized SIENAX for initial GMV and WMV calculations and SIENA for longitudinal brain volume loss estimation.

Main Results:

• HAMS patients (n=14) exhibited significantly lower baseline GMV and WMV compared to non-HAMS patients (p < 0.01).
• Over 24 months, HAMS patients demonstrated a significantly higher rate of GMV decrease (-0.77%) versus non-HAMS patients (-0.61%, p < 0.001).
• This accelerated GMV atrophy in HAMS was observed independently of new lesion formation or relapse activity during follow-up.

Conclusions:

• Highly active multiple sclerosis is associated with accelerated gray matter atrophy over a 24-month period.
• Brain volume loss in HAMS patients progresses faster than in non-HAMS patients, irrespective of relapse activity.
• These findings highlight the distinct neurodegenerative trajectory in HAMS, emphasizing the need for tailored therapeutic strategies.