Bipolar disorders and deep grey matter in multiple sclerosis: A preliminary quantitative MRI study

Area of Science:

• Neuroscience
• Psychiatry
• Radiology

Background:

• Bipolar disorder (BD) affects approximately 8% of multiple sclerosis (MS) patients.
• Brain damage associated with BD comorbidity in MS remains unclear.
• Subcortical grey matter (scGM) structures are crucial for affective functioning.

Purpose of the Study:

• To investigate the association between brain atrophy, specifically in scGM structures, and the co-occurrence of BD in MS patients.
• To determine if reduced scGM volumes correlate with the presence of BD in individuals with MS.

Main Methods:

• Recruited MS patients with BD and a control group of MS patients without psychiatric disorders.
• Utilized brain MRI to estimate whole brain (WB), white matter (WM), and grey matter (GM) volumes using SIENAX.
• Estimated scGM volumes (putamen, caudate, thalamus, hippocampus, amygdala, nucleus accumbens, pallidus) using the FIRST tool.

Main Results:

• No significant differences in WB, WM, or cortical GM volumes were found between MS patients with and without BD.
• Multiple regression analysis revealed significantly lower volumes of the putamen and nucleus accumbens in MS patients with BD.
• A trend towards significance was observed for reduced pallidus volume in MS patients with BD.

Conclusions:

• Preliminary findings suggest that MS patients with BD exhibit smaller nucleus accumbens and putamen volumes.
• Further research with larger cohorts is needed to confirm these findings and elucidate the underlying structural brain damage.
• Understanding these structural changes is crucial for managing psychiatric comorbidities in MS.