Cognitive impairment at diagnosis predicts 10-year multiple sclerosis progression

Area of Science:

• Neurology
• Neuroimmunology
• Cognitive Neuroscience

Background:

• Cognitive impairment is prevalent in multiple sclerosis (MS), particularly in the secondary progressive (SP) phase.
• Relapsing-remitting MS (RRMS) patients also experience cognitive deficits, impacting long-term outcomes.

Purpose of the Study:

• To examine the association between cognitive dysfunction at diagnosis in newly diagnosed RRMS patients and their long-term disease trajectory.
• To identify specific cognitive tests predictive of disability progression and conversion to SPMS.

Main Methods:

• A 10-year retrospective longitudinal study of 155 newly diagnosed RRMS patients.
• Cognitive function was assessed at baseline using the Rao Brief Repeatable Battery.
• Disability progression (Expanded Disability Status Scale [EDSS] ≥ 4.0) and conversion to SPMS were recorded.

Main Results:

• 43.2% reached EDSS ≥ 4.0, and 21.9% converted to SPMS within 10 years.
• Cognitive impairment at diagnosis significantly increased the risk of reaching EDSS ≥ 4.0 (HR=3.183) and converting to SPMS (HR=2.535).
• Poorer performance on the Selective Reminding Test-Delayed Recall and Symbol Digit Modalities Test predicted higher rates of SPMS conversion.

Conclusions:

• Cognitive impairment, especially in processing speed and memory, is a significant predictor of disability progression and SPMS conversion in early RRMS.
• Routine cognitive assessment at the time of MS diagnosis is essential for prognostication and management.
• Identifying cognitive deficits early can guide interventions to potentially alter long-term MS outcomes.