S3173 Association of Low Vitamin D Levels With Helicobacter pylori Infection: A Systematic Review and Meta-Analysis

Introduction: Vitamin D is not only also crucial to bone metabolism, but it is also important as an immunomodulatory factor, affecting susceptibility to a range of infections. More recently, it has been hypothesized that low serum levels of vitamin D are associated with increased prevalence or persistence of H. pylori infection. However, no comprehensive studies are available up to date. Here, we aim to evaluate the association between low serum vitamin D levels and the risk of H. pylori infection using pooled data from observational studies. Methods: A comprehensive literature search was conducted using PubMed, Semantic Scholar, and Google Scholar from January 2009 through May 2025. Eligible studies were observational in design (cross-sectional or cohort) and assessed the relationship between vitamin D status and H. pylori infection. Studies reporting odds ratios (ORs), or from which ORs could be calculated, were included. A total of 8 studies involving 13,659 participants were selected. Meta-analysis was performed using a random-effects model to calculate the pooled odds ratio (OR) with 95% confidence intervals (CIs). Heterogeneity was assessed using the I2 statistic. Publication bias was evaluated via funnel plot analysis. Results: Eight studies comprising a total of 10,172 patients were included in the meta-analysis. The results demonstrated a significant association between low serum vitamin D levels and H. pylori infection. The pooled OR was 2.23 (95% CI 1.66 to 3.01; P < 0.00001), suggesting that individuals with vitamin D deficiency had more than twice the odds of being infected with H. pylori compared to those with sufficient vitamin D levels. Overall, the heterogeneity among the studies was substantial (I2 = 92%; P < 0.00001), indicating variability in populations, methods, and outcomes assessed. Despite this heterogeneity, the funnel plot revealed a generally symmetrical distribution, suggesting no significant publication bias. Conclusion: This meta-analysis demonstrates a significant association between low serum vitamin D levels and an increased risk of Helicobacter pylori infection. Vitamin D deficiency may represent a modifiable risk factor in H. pylori pathogenesis. These findings support the need for further longitudinal and interventional studies to evaluate the potential role of vitamin D supplementation in preventing or managing H. pylori infection.