Association of Helicobacter pylori infection with the risk of metabolic syndrome and insulin resistance: an updated systematic review and meta-analysis

Background Conflicting results of recent studies on the association between Helicobacter pylori (H. pylori) infection and the risk of insulin resistance and metabolic syndrome explored the need for updated meta-analysis on this issue. Therefore, this systematic review aimed to estimate the pooled effect of H. pylori infection on the risk of insulin resistance and metabolic syndrome. Methods To identify case-control studies and cohort studies evaluating the association of H. pylori infection with insulin resistance and metabolic syndrome, a comprehensive literature search was performed from international databases including Medline (PubMed), Web of Sciences, Scopus, EMBASE, and CINHAL from January 1990 until January 2021. We used odds ratio with its 95% confidence interval to quantify the effect of case-control studies and risk ratio with its 95% CI for the effect of cohort studies. Results 22 studies with 206,911 participants were included for meta-analysis. The pooled estimate of odds ratio between H. pylori infection and metabolic syndrome in case-control studies was 1.19 (95% CI 1.05-1.35; I-2 = 0%), and in cohort studies, the pooled risk ratio was 1.31 (95% CI 1.13-1.51; I-2 = 0%). Besides, case-control studies showed the pooled odds ratio of 1.54 (95% CI 1.19-1.98; I-2 = 6.88%) for the association between H. pylori infection and insulin resistance. Conclusion In this meta-analysis, the results showed that there was a possibility of metabolic syndrome and insulin resistance in case of H. pylori infection.