Identification of early environmental risk factors for irritable bowel syndrome and dyspepsia

Background The role of childhood environment including exposure to infection via siblings and pets in irritable bowel syndrome (IBS) and dyspepsia is relatively unknown. We assessed proxy measures of microbial exposure in early childhood to assess if these are associated with IBS and functional dyspepsia in later life. Methods Participants (n = 767, response rate = 53%) were a random population sample from Sydney, Australia who previously responded to a validated survey. IBS and functional dyspepsia were defined using Rome III criteria. Early environmental risk factors assessed included type of birth delivery, premature birth, breastfeeding, bedroom sharing, and pet exposure (the latter two then combined as early hygiene factors) up to 5 years of age. Post infectious IBS (PI‐IBS) was assessed by development of IBS following gastroenteritis. Key Results In this sample, in adult life 17% developed IBS (of which 20% had PI‐IBS) and 12% functional dyspepsia. Development of IBS was associated with childhood factors—a shorter duration of breastfeeding (odds ratios [OR] = 0.87, 95% CI: 0.78–0.97, p = 0.01), sharing a bedroom (OR = 1.89, 95% CI: 1.73–3.08, p = 0.01), exposure to a herbivore pet (OR = 1.65 (1.10, 2.48), p = 0.02), and hygiene factors (OR = 4.39; 95% CI: 1.89–10.21, p = 0.001). The sole factor associated with functional dyspepsia was exposure to a herbivore pet (1.79; 95% CI: 1.19–2.87, p = 0.02). Conclusions & Inferences Childhood environment factors, particularly bedroom sharing and pet exposure, combined with subsequent risk of microbial exposure are a risk factor for IBS in later life. These associations however need confirmation to rule out any risk of a type I error. View the podcast on this paper at the following sites: Youtube: https://www.youtube.com/watch?v=EVi-_KEb4WQ&feature=em-upload_owner iTunes: https://itunes.apple.com/gb/podcast/neurogastroenterology-motility/id1029473393 The role of childhood environment including microbial exposure in IBS and dyspepsia is relatively unknown but may be an important risk factor for the development of these disorders in later life. We analyzed survey responses in relation to proxy measures of microbial exposure including type of birth delivery, premature birth, breastfeeding, bedroom sharing, and pet exposure from a random sample of 767 Australian participants. Childhood environment factors, particularly bedroom sharing and pet exposure, combined with subsequent risk of microbial exposure are a risk