Benign multiple sclerosis: physical and cognitive impairment follow distinct evolutions

Area of Science:

• Neurology
• Neuroimmunology
• Cognitive Neuroscience

Background:

• Benign multiple sclerosis (BMS) definitions primarily focus on physical disability, often underestimating cognitive impairment.
• Cognitive impairment is a significant, yet frequently overlooked, aspect of BMS progression.

Purpose of the Study:

• To evaluate the longitudinal changes in physical disability and cognitive function in patients with BMS.
• To compare the disease progression of BMS patients with a matched cohort of non-BMS patients.

Main Methods:

• A cohort of 24 BMS patients (diagnosed by 2005 McDonald criteria, relapsing-remitting, ≥10 years duration, EDSS ≤2.0) and 13 non-BMS patients (EDSS 2.5-5.5) were followed for 5 years.
• Cognitive impairment was assessed using a neuropsychological battery, defined as failure in at least two tests.
• Physical disability was measured by the Expanded Disability Status Scale (EDSS) score, with worsening defined as a ≥1 point increase.

Main Results:

• At baseline, 16% of both BMS and non-BMS patients exhibited cognitive impairment.
• After 5 years, only 8% of BMS patients experienced EDSS score worsening, compared to 46% of non-BMS patients (P=0.008).
• The prevalence of cognitive impairment increased to 25% in both groups after 5 years.

Conclusions:

• BMS patients demonstrate superior physical disability outcomes over a 5-year period compared to non-BMS patients.
• Cognitive impairment develops and progresses similarly in both BMS and non-BMS groups.
• Routine neuropsychological assessment is vital for managing BMS, recognizing distinct progression trajectories in cognitive and physical domains.