Malabsorption, Orocecal Transit Time and Small Intestinal Bacterial Overgrowth in Type 2 Diabetic Patients: A Connection

Abstract

Type 2 diabetes mellitus consists of dysfunctions characterized by hyperglycemia and resulting from combination of resistance to insulin action and inadequate insulin secretion. Most of diabetic patients report significant gastrointestinal symptoms. Entire GI tract can be affected by diabetes from oral cavity to large bowel and anorectal region. Proteins, carbohydrates, fats, and most fluids are absorbed in small intestine. Malabsorption may occurs when proper absorption of nutrients does not take place due to bacterial overgrowth or altered gut motility. The present study was planned to measure various malabsorption parameters in type 2 diabetic patients. 175 patients and 175 age and sex matched healthy controls attending Endocrinology Clinic in PGI, Chandigarh were enrolled. Lactose intolerance was measured by using noninvasive lactose hydrogen breath test. Urinary D-xylose and fecal fat were estimated using standard methods. Orocecal transit time and small intestinal bacterial overgrowth were measured using non-invasive lactulose and glucose breath test respectively. Out of 175 diabetic patients enrolled, 87 were males while among 175 healthy subjects 88 were males. SIBO was observed in 14.8 % type 2 diabetic patients and in 2.8 % of controls. There was statistically significant increase (p \ 0.002) in OCTT in type 2 diabetic patients compared with controls. OCTT was observed to be more delayed (p \ 0.003) in patients who were found to have SIBO than in patients without SIBO. Lactose intolerance was observed in 60 % diabetic patients and 39.4 % in controls. Urinary D-xylose levels were also lower in case of diabetic patients but no significant difference was found in 72 h fecal fat excretion among diabetic patients and controls. Urinary D-xylose and lactose intolerance in SIBO positive type 2 diabetic patients was more severe as compared to SIBO negative diabetic patients. From this study we can conclude that delayed OCTT may have led to SIBO which may have instigated the process of malabsorption among type 2 diabetic patients.

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

“…Similar results were reported in another study in T2DM, which found that SIBO could lead to vitamin deficiencies, fat malabsorption, and under-nutrition. 9 Therefore, these findings suggest that there is an inverse association between SIBO and BMI.…”

“…Rana et al. 9 reported that SIBO was observed in 14.8% T2DM patients and in 2.8% of healthy controls. Rana et al.…”

“…SIBO and intestinal microbiota have been associated with various diseases, such as Crohn’s disease, irritable bowel syndrome, 1 , 2 functional gastrointestinal disorders, 3 deep venous thrombosis, 4 nonalcoholic fatty liver disease, 5 – 7 and diabetes. 8 , 9 Type 2 diabetes (T2DM) is a metabolic disease that is characterized by decreased insulin secretion and variable degrees of peripheral insulin resistance, which leads to hyperglycemia. Recently, many studies focused on a new mechanism where SIBO is involved in the development of T2DM.…”

Breath Tests for the Non-invasive Diagnosis of Small Intestinal Bacterial Overgrowth: A Systematic Review With Meta-analysis

“…In the group of patients without any predisposing conditions, we included subjects in which factors predisposing to SIBO such as abdominal surgery, celiac disease, connective tissue disorders, and others as listed in. [4][5][6][7][8][9][10] In 6 studies the sub-category of patients without any predisposing conditions was considered. 21,22,24,28,30,32 Three hundred and forty patients were enrolled in this subgroup, which was constituted mainly by healthy controls, elderly patients with diarrhea, and IBS patients.…”

“…Several processes predispose to bacterial overgrowth such as anatomical/structural changes of the small intestine (previous gastrointestinal surgery), motility disorders (such as gastroparesis), metabolic disorders (gastric hypochlorhydria and diabetes), organ system dysfunctions (cirrhosis, renal failure, chronic pancreatitis, Crohn's disease, and celiac disease), medications (prolonged use of proton pump inhibitors and antibiotics), and irritable bowel syndrome (IBS). [4][5][6][7][8][9][10] The most common symptoms are diarrhea, abdominal pain and bloating, but weight loss, malnutrition, and deficiency of vitamins (B12, D, A, and E) and minerals (iron and calcium) are possible. 1 The flora of SIBO patients is mainly characterized by the prevalence of coliform bacteria and anaerobes, which cause fermentation of carbohydrates, compete with vitamin and micronutrient absorption and engender microscopic mucosal inflammation, thus leading to the above described symptoms.…”