Dyspepsia and irritable bowel syndrome after a Salmonella gastroenteritis outbreak: one-year follow-up cohort study.

BACKGROUND & AIMS It has been reported that some patients develop functional digestive disorders, particularly irritable bowel syndrome (IBS), after acute gastroenteritis (AGE). However, the presence of dyspepsia has not been specifically addressed. We prospectively evaluated development of dyspepsia and IBS during a 1-year follow-up in a cohort of adult patients affected by a Salmonella enteritidis AGE outbreak. METHODS Questionnaires were sent to 1878 potential participants at baseline and 3, 6, and 12 months; 677 had experienced a Salmonella enteritidis AGE on June 23, 2002, and 1201 had not (randomly selected controls, matched for village of residence, age, and sex). At 12 months, 271 patients and 335 controls returned the questionnaires. Data permitted the establishment of dyspepsia and IBS diagnosis by Rome II criteria. RESULTS Before the AGE outbreak, the prevalence of dyspepsia was similar in cases and controls (2.5% vs 3.8%); the prevalence of IBS was also similar (2.9% vs 2.3%). At 3, 6, and 12 months, the prevalence of both dyspepsia and IBS had increased significantly in exposed compared with unexposed subjects. Overlap between dyspepsia and IBS was frequent. At 1 year, the relative risk for development of dyspepsia was 5.2 (95% confidence interval, 2.7-9.8) and for IBS was 7.8 (95% confidence interval, 3.1-19.7). Prolonged abdominal pain and vomiting during AGE were positive predictors of dyspepsia. No predictive factors for IBS were found. CONCLUSIONS Salmonella gastroenteritis is a significant risk factor not only for IBS but also for dyspepsia; at 1 year of follow-up, 1 in 7 and 1 in 10 subjects developed dyspepsia or IBS, respectively.