Helicobacter pylori infection increases the risk of nonalcoholic fatty liver disease: Possible relationship from an updated meta-analysis

BACKGROUND: The relationship between Helicobacter pylori (H pylori) infection and nonalcoholic fatty liver disease (NAFLD) has long been debated. Although it has been investigated in many observational studies, the results remain controversial. Therefore, we performed an updated meta-analysis to assess the association between H pylori infection and risk of NAFLD by collecting relevant articles. METHODS: Literature collections were conducted by searching PubMed, EMBASE, Web of Science and Cochrane Library databases. Pooled odds ratios with corresponding 95% confidence intervals were calculated to estimate the strength of the link between H pylori infection and NAFLD using Stata 12.0 software. RESULTS: 28 studies with 68,047 cases of NAFLD patients and 134,866 controls were finally included in the meta-analysis. Overall, The results suggested a 27.5% increased risk of developing NAFLD in patients with H pylori infection (odds ratios 1.275 95% confidence intervals 1.179–1.379), although significant heterogeneity was observed. There is no significant publication bias observed based on the funnel plot and Begg test. Subgroup analysis revealed that variables of the study design, study region, publication year, and the method of diagnosing H pylori and NAFLD all contribute to the high heterogeneity, while the positive correlation was seen in all subgroup analysis. CONCLUSION: This meta-analysis disclosed 1.275-fold increased risk of the occurrence and development of NAFLD in H pylori (+) group compared with the H pylori (−) group, indicating that H pylori is a serious risk factor in patients susceptible to NAFLD.