Childhood Maltreatment and Its Pathways to Irritable Bowel Syndrome in Adulthood: Insights From Sequential Mediation Analysis.

Childhood maltreatment has been associated with an increased risk of irritable bowel syndrome (IBS) in adulthood, but the longitudinal relationship and underlying mechanisms remain underexplored. Using data from the UK Biobank, this cohort study investigated the association between childhood maltreatment and the onset of IBS in adulthood and explored potential mediating pathways. A total of 108,365 participants (mean age: 34.57 [SD: 4.81] years; 57.2% were female) were followed up from age 30 onwards (or January 1, 1985, whichever was later) until the first IBS diagnosis, death, or the end of follow-up, whichever occurred first. Childhood maltreatment was assessed through self-reported data, and incident IBS cases were identified using ICD-10 codes, with subtypes classified by Rome III criteria. Cox proportional hazards, sequential mediation analyses, and multinomial logistic regression were performed. Over a mean follow-up of 35.6 years, 5806 incident IBS cases were recorded. A positive association was observed between cumulative childhood maltreatment and incident IBS (HR: 1.10; 95% CI: 1.07-1.12). Among individual maltreatment types, emotional neglect showed the strongest association with IBS (HR: 1.27; 95% CI: 1.20-1.35). Sequential mediation analyses indicated that psychological adversity accounted for the largest proportion of the indirect effect (15.3%-17.0%), followed by socioeconomic status, lifestyle behaviours, and biological alterations. These findings emphasise the need for prevention strategies to reduce childhood maltreatment and mitigate its long-term health impacts. Tailored interventions focussing on psychosocial support, addressing socioeconomic disparities, and promoting healthy lifestyle changes may further reduce IBS risk in affected individuals.