Infectious Gastroenteritis and Risk of Developing Inflammatory Bowel Disease

Background & Aims: Infectious gastroenteritis (IGE) is known to exacerbate previously diagnosed inflammatory bowel disease (IBD). However, limited data are available describing a causal link between IGE and incident IBD. Methods: By using a medical encounter data repository of active duty military personnel, a study was conducted to assess IBD risk in subjects with an antecedent case of IGE. Results: Between 1999 and 2006, there were 3019 incident IBD cases and 11,646 matched controls who were evaluated in a conditional logistic regression model. To control for potential misclassification, IGE episodes within 6 months of IBD diagnosis were excluded as exposures. After adjusting for potential confounders, an episode of IGE increased the risk of IBD (odds ratio, 1.40; 95% confidence interval, 1.19–1.66). The risk was slightly higher for Crohn's disease compared with ulcerative colitis. In addition, there was an approximate 5-fold increase in IBD risk for persons with a previous irritable bowel syndrome diagnosis. Conclusions: These data support theories that the initiation of IBD is a multifactorial process that might include the disruption of normal gut homeostatic mechanisms. Further studies are warranted to evaluate the pathogen-specific risks, identify susceptible populations, and better understand the pathophysiologic relationship between IGE and IBD.