Disrupted principal network organisation in multiple sclerosis relates to disability

Area of Science:

• Neuroscience
• Medical Imaging
• Neurology

Background:

• Structural network analysis using diffusion imaging reveals white matter connection alterations in multiple sclerosis (MS).
• The organization and clinical relevance of principal networks (PNs) in MS subtypes remain underexplored.

Purpose of the Study:

• To investigate the organization of principal networks (PNs) in different multiple sclerosis (MS) subtypes.
• To assess the clinical relevance of PNs by correlating network properties with disability in MS patients.

Main Methods:

• Structural networks were reconstructed from diffusion MRI data in relapsing-remitting MS (RRMS), primary progressive MS (PPMS), secondary progressive MS (SPMS), and healthy controls (HCs).
• Principal network (PN) analysis was performed, comparing hub strengths and network composition across groups.
• Regression analysis examined associations between nodal strength of the first and second PNs (PN1, PN2) and clinical disability.

Main Results:

• MS patients showed preserved hub numbers but reduced strength in some network hubs compared to HCs.
• PN1 composition differed in SPMS (lacking right thalamus), and PN2 composition differed in MS (lacking right putamen) and SPMS (lacking right thalamus).
• Reduced nodal strength in the right thalamus and putamen within PNs strongly correlated with higher clinical disability.

Conclusions:

• Principal network analysis reveals distinct patterns of brain network disruption across MS subtypes.
• Alterations in specific network hubs, particularly the right thalamus and putamen, are clinically relevant and associated with disability in MS.