Microstructural changes in the brain in elderly patients with irritable bowel syndrome

Area of Science:

• Neuroimaging
• Gastroenterology
• Geriatrics

Background:

• Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disorder affecting quality of life.
• The impact of brain structural changes on elderly IBS patients remains poorly understood.
• Psychological stress is increasingly recognized as a contributing factor in IBS pathogenesis.

Purpose of the Study:

• To investigate the relationship between brain structural alterations (gray matter volume and white matter density) and psychological stress in elderly IBS patients.
• To identify specific brain regions affected by these changes in the elderly IBS population.

Main Methods:

• Structural magnetic resonance imaging (MRI) was performed on 18 elderly IBS patients and 12 healthy controls.
• Voxel-based morphometry (VBM) was used to analyze gray matter volume (GMV) differences.
• Diffusion tensor imaging (DTI) was employed to assess white matter integrity (fractional anisotropy and mean diffusivity).

Main Results:

• IBS patients exhibited reduced GMV in the cingulate gyrus, occipital lobe, hippocampus, frontal lobe, and limbic lobe.
• Increased GMV was observed in the insula, superior temporal gyrus, angular gyrus, and supramarginal gyrus of IBS patients.
• DTI revealed lower fractional anisotropy and higher mean diffusivity in white matter tracts, including the corpus callosum, internal capsule, and fornix, in IBS patients.

Conclusions:

• Structural brain changes, encompassing both gray matter and white matter abnormalities, are associated with IBS in the elderly.
• Psychological stress, potentially mediated by the hypothalamic-pituitary-adrenal axis, is a significant factor in the development and progression of IBS.
• These findings highlight the brain-gut axis's role in elderly IBS and suggest potential therapeutic targets.