From Gut Feeling to Gray Matter: Mapping Defecation Urgency in Irritable Bowel Syndrome

BACKGROUND & AIMS: Defecation urgency is a common and highly distressing symptom in patients with irritable bowel syndrome (IBS), but its definition remains insufficiently clear. We aimed to compare different measures of urgency, real-life and rectal sensation thresholds, and their clinical and neural correlates. METHODS: A total of 150 patients with moderate-severe IBS were enrolled in this cross-sectional study conducted at a specialized gastroenterology clinic. Defecation urgency was evaluated using gastrointestinal symptom diaries, questionnaires, and rectal sensation thresholds. Structural magnetic resonance imaging was performed to explore associations between regional gray matter volume (GMV) and urgency-related measures. Statistical analyses were conducted using nonparametric tests and partial correlation analyses, adjusted for relevant covariates. A P value of