Abstract
BACKGROUND: Helicobacter pylori (H. pylori) infection is linked to various gastrointestinal and systemic diseases, including diabetes mellitus (DM). This study synthesizes evidence to determine the association between H. pylori infection and the risk of developing DM. OBJECTIVES: To quantify the odds ratio (OR) of DM in individuals with H. pylori infection and explore variations across different subgroups. METHODS: A systematic review and meta-analysis were conducted following PRISMA 2020 guidelines. Databases including Medline, Web of Science, Scopus, EMBASE, Ovid, and CINHAL were searched for case-control studies from January 1990 to January 2025. Eligible studies investigated the association between H. pylori and DM. Data extraction was performed independently by two reviewers, and study quality was assessed using the Modified Newcastle-Ottawa Scale (NOS). Random-effects models were utilized to calculate pooled ORs, with heterogeneity assessed via I² statistic. Subgroup analyses included H. pylori detection methods, age groups, geographic regions, DM types, HbA1c levels, duration of DM, and study quality. RESULTS: From 280 records, 45 case-control studies were included, involving 529 million diabetes cases worldwide in 2021. The pooled OR was 1.547 (95% CI: 1.243-1.926), indicating that H. pylori infection increases the risk of DM by approximately 1.56 times. Heterogeneity was moderate (I² = 46.03%). Subgroup analyses showed stronger associations with non-invasive H. pylori detection methods (OR = 1.99), in the 40-60 age group (OR = 2.00), and for type 2 diabetes (OR = 2.25). Geographic variations were significant, with Asia showing the highest OR (2.17). No significant publication bias was detected, and sensitivity analyses confirmed the robustness of our findings. CONCLUSION: This meta-analysis confirms a significant association between H. pylori infection and an increased risk of DM, particularly type 2. The findings underscore the potential benefits of considering H. pylori testing in diabetes management strategies, especially in high-risk populations. Further research should focus on longitudinal studies to establish causality and explore biological mechanisms. REGISTRATION: This review was registered in PROSPERO (CRD42025637126).