Association between Helicobacter pylori infection and type 2 diabetes mellitus: a retrospective cohort study and bioinformatics analysis

Abstract Purpose This study aimed to preliminarily investigate the association and possible mechanisms between Helicobacter. pylori (H. pylori) infection and type 2 diabetes mellitus (T2DM) through data collection, statistical analysis, and bioinformatics analysis. Methods A retrospective cohort study, including a total of 4406 participants who attended annual health checkups at Xian GEM Flower Changqing Hospital, was conducted to explore the correlation between the incidence of T2DM and H. pylori infection. To uncover the potential mechanisms underlying the interaction between the two diseases, differentially expressed genes (DEGs) common to T2DM and H. pylori infection were identified using the GEO database and Venn diagrams. These DEGs were then analyzed through Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and protein-protein interaction (PPI) analysis. Results In total, 2053 participants were classified into the H. pylori-positive group and 2353 into the H. pylori-negative group. H. pylori infection was associated with a higher risk of T2DM occurrence (adjusted HR 1.59; 95% CI 1.17–2.15, P = 0.003). The average disease-free survival time was 34.81 months (95% CI 34.60-35.03 months) in the H. pylori positive group and 35.42 months (95% CI 35.28–35.56 months) in the H. pylori negative group. Multivariate analysis and subgroup analyses also showed that H. pylori infection increased the risk of developing T2DM. A total of 21 DEGs between T2DM and H. pylori infection were identified and enriched in 7 signaling pathways, indicating specific protein interactions. Conclusions The prevalence of T2DM was associated with H. pylori infection. T2DM and H. pylori infection may interact with each other through metabolic and immune pathways.