The role of small intestinal bacterial overgrowth in the pathogenesis of hyperlipidemia

Introduction: Small intestinal bacterial overgrowth may cause the hyperlipidemia appearance by enterohepatic circulation disturbance which evolves on the background of the early bile acids deconjugation with further endotoxin production and oxidative stress in the liver with hyperproduction of cholesterol and atherogenic lipoproteins. The aim: the determination of prevalence and features of SIBO in a series of patients with hyperlipidemia and in control subjects.

Materials and methods: Nineteen patients with hyperlipidemia and ten control subjects were studied. Small intestinal bacterial overgrowth was assessed by a lactulose breath test. Such biochemical markers as CRP, ALT, AST, GGTP, apolipoprotein B, bilirubin, cholesterol and lipid profile were determined. Except the routine interpretation of lactulose breath test, which contains the SIBO detection, small intestinal transit time and hydrogen level evaluation with next comparison between groups of patients was realized.

Results: Small intestinal bacterial overgrowth was present in 78.9% of patients with hyperlipidemia and 40% in control subjects. The maximal dose of H2 was particularly higher in patients with hyperlipidemia in comparison with control group (94,7±13,69 vs. 36,13±5,4). There was a strong correlation between AST level and SIBO existence in both groups (r=1). Positive connection between LDL, TG, VLDL and the dose of exhaled hydrogen on 120 minute (r=0.6, r= 0.62, r=0.7 respectively) and strong negative correlation between HDL and 120 minute dose (r=-0.74) in main group was marked.

Conclusions: Patients with hyperlipidemia have a higher prevalence of small intestinal bacterial overgrowth and there is a relationship between H2 rate and LDL, TG, VLDL.