Obesity Is Inversely Related to Hydrogen-Producing Small Intestinal Bacterial Overgrowth in Non-Constipation Irritable Bowel Syndrome

Abstract

There have been inconsistent findings on the association of obesity and non-constipation irritable bowel syndrome (IBS). Small intestinal bacterial overgrowth (SIBO) with hydrogen (H2) gas forming-microflora causes non-constipation IBS. But, the effect of H2 producing SIBO on obesity in non-constipation IBS patients has not been studied yet. The aim of this study was to investigate the association between obesity and SIBO in non-constipation IBS patients. We reviewed the charts of patients who showed IBS symptoms along with the documented results of their lactulose hydrogen breath test (LHBT) for SIBO. Multivariate models were used to assess the association between obesity and SIBO. Four-hundred fifty-eight patients were retrospectively included in the study. Of the 485 IBS patients, 158 (30.7%) subjects had positive results for LHBT. Subjects without SIBO showed significantly higher levels of body mass index (24.8 vs. 23.3; P < 0.001) and waist circumference (86.5 vs. 82.7; P < 0.001) as compared to subjects with SIBO. In multivariate analysis, the odds ratios of SIBO were 0.396 (P = 0.018) for obesity and 0.482 (P = 0.021) for abdominal obesity. This is the first human study to demonstrate that obesity is inversely related to SIBO with H2 gas production in non-constipation IBS patients.

In Vitro Evaluation of Different Prebiotics on the Modulation of Gut Microbiota Composition and Function in Morbid Obese and Normal-Weight Subjects

“…In the context of obesity, an inverse association between body mass index and H 2 and CH 4 gas detection in breath tests has been reported [41,42], which is in good agreement with the lower cumulative gas in MOB cultures obtained herein. Although emphasis has been given to the potential inflammatory or carcinogenic properties of colonic gases, emerging evidence suggests that these gases might have a beneficial effect in colonic health [43].…”

Association between small intestinal bacterial overgrowth and beta-cell function of type 2 diabetes

“…These results were consistent with those a previous study that showed that subjects with SIBO had significantly lower BMI and waist circumference compared with subjects without SIBO in non-constipation irritable bowel syndrome. 28 Although it is difficult to provide definite clarification between BMI and SIBO in T2DM in this study, there are several potential explanations for this association, based on previous studies. SIBO may be accompanied by malabsorption, which can lead to a variety of nutrient deficiencies and weight loss.…”

A meta‐analysis on small intestinal bacterial overgrowth in patients with different subtypes of irritable bowel syndrome

“…showed that the prevalence of SIBO in patients with IBS varies between 39% and 54%. However, these meta‐analyses were published about a decade ago, and there has been a substantial influx of good quality studies using glucose hydrogen breath test (GHBT), and lactulose hydrogen breath test (LHBT) . Also, the earlier meta‐analysis focused on breath tests only, which are non‐invasive alternatives, albeit inferior to the gold standard method of quantitative upper gut aspirate culture.…”

“…However, these meta-analyses were published about a decade ago, and there has been a substantial influx of good quality studies using glucose hydrogen breath test (GHBT), 13,20,22,[31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47] and lactulose hydrogen breath test (LHBT). 11,14,22,23,26,34,[48][49][50][51][52][53][54][55][56][57][58][59][60][61][62][63][64][65][66] Also, the earlier meta-analysis focused on breath tests only, 11,20,22,23,26,…”