The association between Helicobacter pylori infection and functional dyspepsia in patients with irritable bowel syndrome

OBJECTIVE: Irritable bowel syndrome (IBS) is associated with an exaggerated response to a variety of physiological and nonphysiological gastrointestinal stimuli. Many patients with IBS also have functional dyspepsia. Our aim was to examine the hypothesis that Helicobacter pylori (H. pylori) infection may predispose IBS patients to functional dyspepsia. METHODS: In 69 IBS patients, dyspeptic symptoms, H. pylori status, and sociodemographic and psychological variables (perceived stress, trait anxiety, and depression) were assessed. Sociodemographic and psychological variables were also evaluated in 52 control subjects. RESULTS: Mean scores for perceived stress (17.1 +/- 6.0 vs 14.9 +/- 6.0, p = 0.05), trait anxiety (45.6 +/- 9.1 vs 41.1 +/- 7.8, p = 0.004) and depression (9.9 +/- 8.4 vs 5.0 +/- 5.5, p = 0.0002) were higher in IBS patients than in controls. In all, 33 of the 69 patients (47.8%) had H. pylori infection, and this was associated with relevant symptoms of epigastric pain (odds ratio [OR] = 6.77, 95% confidence interval [CI] 1.89-24.3) and postprandial upper abdominal fullness (OR = 4.23, 95% CI 1.38-13.2). H. pylori infection and female gender were independent predictors of the presence of relevant dyspepsia (OR = 8.31, 95% CI 2.35-29.5 and 6.06, 95% CI 1.71-21.5, respectively). Symptom intensity was associated with the level of perceived stress (total relevant symptom number > or =3 vs <3, OR = 1.16 per point on a 40-point perceived stress scale, 95% CI 1.01-1.34). CONCLUSIONS: In IBS patients, the presence of dyspepsia is associated with H. pylori infection, female gender, and perceived stress.