Higher visceral to subcutaneous fat ratio is associated with small intestinal bacterial overgrowth

There is a lack of studies evaluating the association between small intestinal bacterial overgrowth (SIBO) and abdominal fat. The aim of this study was to evaluate whether visceral fat area (VFA), subcutaneous fat area (SFA) or visceral to subcutaneous fat ratio (VFA/SFA ratio) were associated with SIBO.

In this case-control study, 152 eligible patients submitted to glucose hydrogen/methane breath test who also had computed tomography (CT) of the abdomen performed were included. Clinical and demographic information was obtained. VFA and SFA were measured using Image J software at lumbar 3 level on CT cross-sectional image of the 152 patients included in this study, 68 patients (44.7%) tested positive for SIBO. In the univariate analysis, the presence of SIBO was associated with older age (65.2 ± 1.5 vs. 59.3 ± 1.5, p = 0.007); type 2 diabetes mellitus (33.8% vs. 17.9%; p = 0.019); hypertension (63.2% vs. 39.3%; p = 0.003); metabolic syndrome (85.3% vs. 64.3%; p = 0.003); and higher VFA/SFA ratio (1.0 ± 0.1 vs. 0.7 ± 0.1; p < 0.001). In multivariate analysis, metabolic syndrome (odds ratio [OR]: 2.5; 95% confidence interval [CI]: 1.1-5.7; p = 0.035) and higher VFA/SFA ratio (OR: 3.3; 95% CI: 1.6-7.2; p = 0.002) remained independently associated with SIBO.

The presence of SIBO was found to be associated with high VFA/SFA ratio measured from cross-sectional CT image.