RT Journal Article SR Electronic T1 Eight year prognosis of postinfectious irritable bowel syndrome following waterborne bacterial dysentery JF Gut JO Gut FD BMJ Publishing Group Ltd and British Society of Gastroenterology SP 605 OP 611 DO 10.1136/gut.2009.202234 VO 59 IS 5 A1 John K Marshall A1 Marroon Thabane A1 Amit X Garg A1 William F Clark A1 Paul Moayyedi A1 Stephen M Collins A1 Walkerton Health Study Investigators YR 2010 UL http://gut.bmj.com/content/59/5/605.abstract AB Background Although postinfectious irritable bowel syndrome (PI-IBS) is a well-recognised complication of acute gastroenteritis, its prognosis remains poorly defined. The natural history of PI-IBS was assessed among participants in the Walkerton Health Study (WHS), which has followed the long-term effects of a large outbreak of acute gastroenteritis related to municipal water contamination in May 2000.Methods WHS participants were invited to return for annual assessment at a research clinic. Adult residents of Walkerton at the time of the outbreak who enrolled in 2002/2003 and returned for assessment in 2008 were eligible for a PI-IBS study cohort if they had no prior history of IBS or inflammatory bowel disease. A modified Bowel Disease Questionnaire was used to diagnose IBS by Rome I criteria and to identify IBS subtypes.Results Of 4561 WHS participants, 2451 returned for their 8 year assessment and 1166 were eligible for the PI-IBS study cohort (688 females, mean age 46.2 years). The prevalence of IBS among 742 eligible subjects who suffered acute gastroenteritis during the outbreak declined from 28.3% after 2–3 years to 15.4% after 8 years, but remained significantly increased compared with controls who did not have acute gastroenteritis (OR 3.12; 95% CI 1.99 to 5.04). Independent risk factors for PI-IBS at 8 years included female gender, younger age, prior anxiety/depression, and fever or weight loss during the acute enteric illness. IBS subtypes were not stable over time.Conclusions Acute gastroenteritis can trigger IBS symptoms that persist for at least 8 years. Characteristics of the host and the acute enteric illness can predict the long-term risk of PI-IBS.