Gut–Brain Axis Dysfunction in Patients With Irritable Bowel Syndrome

Abstract

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterized by abdominal pain and altered bowel habits. Increasing evidence suggests a critical role of the gut–brain axis in IBS pathogenesis. This study investigated gut microbiota composition, psychological profiles, and neuroimaging findings in 180 IBS patients and 90 healthy controls. Altered microbial diversity, increased anxiety scores, and changes in functional brain connectivity were observed in IBS patients. Multivariate analysis revealed significant correlations between microbial alterations and symptom severity. These findings support a biopsychosocial model of IBS and highlight the potential of integrative therapeutic approaches targeting both gut and brain mechanisms.