Predictive value of synaptic plasticity for functional decline in patients with multiple sclerosis

Area of Science:

• Neuroscience
• Clinical Neurology
• Neurorehabilitation

Background:

• Quadripulse (QPS)-induced synaptic plasticity was previously linked to cognitive and motor functions in multiple sclerosis (MS) patients.
• This plasticity was not found to be reduced in MS patients compared to healthy controls (HCs).

Purpose of the Study:

• To investigate the association between QPS-induced synaptic plasticity and the progression of motor and cognitive impairments in MS.
• To determine if reduced baseline plasticity predicts functional decline in MS patients.

Main Methods:

• QPS-induced plasticity was assessed in 80 MS patients and 69 HCs.
• Motor, cognitive functions, and disability were monitored annually for a median of 2 years.
• Statistical analyses included linear mixed-effects models and Cox proportional hazard models.

Main Results:

• MS patients experiencing decline in manual dexterity or visuospatial memory showed significantly lower baseline synaptic plasticity.
• Baseline plasticity predicted decline in visuospatial learning and memory (AUC=0.85).
• No overall clinically relevant functional changes were observed in the cohort during the follow-up period.

Conclusions:

• QPS-induced synaptic plasticity may be associated with clinically significant functional decline in MS.
• Further research with longer follow-up and higher rates of decline is needed.
• Variability in cognitive performance highlights the need for robust neuropsychological testing.