Background: Type II diabetes mellitus (T2DM) is the prevalent type of diabetes in the world. Prediabetic patients are the most probable group to get diabetes. Several studies have mentioned the role of inflammation in the incidence of diabetes. The origin of inflammation can be infection such as Helicobacter pylori (HP) infection. This study was designed to explore the effect of HP eradication on insulin resistance.

Materials and methods: This single-blind randomized controlled clinical trial was conducted in 2014-2015. The sample size consisted of 49 individuals who were in prediabetes stage with HP infection. Patients with positive stool antigen were allocated randomly into two groups. The treatment group took medication to eradicate HP infection by the routine method of four-drug eradication. However, placebo capsules and tablets were given to the patients in the placebo group. Then fasting plasma glucose (FPG), fasting plasma insulin (FPI), and quantitative C-reactive protein (CRP) levels were measured and homeostatic model assessment of insulin resistance (HOMA-IR), homeostatic model assessment of beta-cell function (HOMA-B), Matsuda index, insulinogenic index, and disposition index were calculated.

Results: Results of this study showed that FPI and HOMA-IR increased significantly (P value of FPI = 0.023 and P value of HOMA-IR = 0.019) after HP eradication in the treatment group. On the other hand, comparison of differences at the baseline and after 6 weeks in FPG (P value = 0.045), FPI (P value = 0.013), and HOMA-B (P value = 0.038) revealed significant differences between the placebo group and treatment group.

Conclusion: Results showed that HP eradication by a 2-week antibiotic medication did not decrease insulin resistance and even increased FPI and insulin resistance indices. So HP eradication among prediabetic patients is not recommended for the decrease of insulin resistance and postponement of the development of diabetes mellitus.