Irritable Bowel Syndrome: Symptom Severity does not Depend on Whether Hydrogen Generation Occurs in the Small Intestine or Colon

Abstract

AIM: Compare symptom occurrence and severity among IBS patients with an early vs. late increase in H2 excretion, as measured by LBT, and evaluate the association between symptom severity and global H2 global excretion. METHODS: Patients with an IBS diagnosis (Rome III criteria) as well as healthy subjects were enrolled consecutively. Subjects were asked to fill in a validated symptom-severity questionnaire (IBS-SSS) and to undergo a LBT. The area under the curve (AUC) was calculated for each LBT hydrogen/time curve. RESULTS: This analysis included 160 IBS and 45 healthy control subjects. An early increase in H2 excretion was observed in 53% of IBS subjects, and this was not significantly different from that observed in healthy subjects. There was also no significant difference in symptom pattern or severity between IBS patients with early vs. late increases in H2 excretion. However, a significant correlation between symptom severity and AUC value was observed (R2: 0.4, 95% CI: 0.1-0.6, p=0.02). CONCLUSION: Symptom pattern and severity was not significantly different among IBS patients with early vs. late increases in H2 excretion. However, the severity of IBS symptoms was significantly associated with global H2 excretion, as measured by the AUC.