Sex-specific brain microstructural reorganization in irritable bowel syndrome

Area of Science:

• Neuroimaging
• Gastroenterology
• Sex Differences Research

Background:

• Preliminary evidence indicates sex-based variations in brain microstructure for individuals with irritable bowel syndrome (IBS).
• Understanding these differences is crucial for targeted IBS management.

Purpose of the Study:

• To investigate sex-dependent differences in brain microstructure and organization in a large IBS cohort versus healthy controls.
• To test hypotheses regarding increased axonal strength, myelination, and sensory sensitivity in female IBS patients.

Main Methods:

• Diffusion tensor imaging (DTI) and clinical assessments were performed on 100 healthy controls and 152 IBS participants.
• Whole-brain voxel-wise analyses examined microstructural metrics (fractional anisotropy, diffusivity, track density) and sensory awareness/sensitivity.

Main Results:

• Female IBS participants displayed significant microstructural alterations in sensorimotor, corticothalamic, and basal ganglia circuits compared to males.
• These alterations correlated with increased symptom severity, somatic awareness, and sensory sensitivity in females.

Conclusions:

• Findings support the hypothesis that central hypersensitivity to multiple sensory stimuli contributes to symptom etiology and maintenance in females with IBS.
• Sex-specific brain alterations in pain and sensory processing pathways are implicated in IBS pathophysiology.