Environmental risk factors for inflammatory bowel disease: A case control study in Southeast Asian children

Aim: Early-life environmental exposure, which has important implications in the pathogenesis of inflammatory bowel disease (IBD), is not well understood in Asian children. We examined environmental factors prior to the development of childhood IBD in a Southeast Asian population.

Methods: We conducted a case control study in IBD diagnosed before 18 years of age and controls matched by gender, age and ethnicity. A questionnaire recording medical, family, dietary and social histories, home environment, childhood diseases and immunisation status was used.

Results: In a multivariate analysis involving 70 children with IBD (Crohn's disease (CD) = 38; ulcerative colitis (UC) = 32) and 140 controls, childhood acute gastroenteritis (odds ratio (OR): IBD 6.9; CD 7.8; UC 5.8) and excessive antibiotic usage in early childhood (OR: IBD 5.3; CD 4.2; UC 4.8) were significantly associated with IBD, CD and UC. Having a fish or turtle aquarium (OR 6.0), major stressful life events (OR 5.6) and attending the same school concurrently with a sibling (OR 2.9) were significant risk factors for IBD. Duration of breastfeeding >6 months (OR: IBD 0.4; UC 0.2) and safe water consumption (OR: IBD 0.2; UC 0.2) reduced the odds of having IBD and UC, respectively. Being vaccinated for rotavirus reduced the odds of developing IBD (OR 0.1).

Conclusions: Several risk and protective factors were identified in this environmental risk study in Southeast Asian children with IBD. This knowledge has important implications in understanding disease aetiology and future prevention strategies to reduce the development of IBD in Southeast Asian children.