A cohort study on Helicobacter pylori infection associated with nonalcoholic fatty liver disease.

BACKGROUND: Previous studies have suggested a link between Helicobacter pylori (H. pylori) infection and nonalcoholic fatty liver disease (NAFLD), yet large-scale longitudinal studies are lacking to elucidate this association.

METHODS: A cohort study of 17,028 adults without NAFLD at baseline, who participated in a repeated health screening examination including an H. pylori-specific immunoglobulin G antibody test, was conducted to evaluate the association between H. pylori and NAFLD development. Fatty liver was diagnosed by ultrasonography.

RESULTS: During the 83,130 person-years follow-up, participants with H. pylori infection had a higher rate of incident NAFLD than those who were uninfected. In a multivariable model adjusted for age, sex, body mass index, smoking status, alcohol intake, regular exercise, year of screening exam, and education level, the hazard ratio (HR) for NAFLD development in participants with H. pylori infection compared to those without infection was 1.21 [95% confidence interval (CI), 1.10-1.34]. The association persisted after further adjustment for metabolic variables, inflammatory marker, and liver enzymes. The association between H. pylori and NAFLD was still evident in an analysis using fatty liver index as a surrogate marker of NAFLD. In addition, the association between H. pylori infection and incident NAFLD did not differ across clinically relevant subgroups evaluated.

CONCLUSIONS: H. pylori infection was significantly associated with the development of NAFLD, independent of metabolic and inflammatory risk factors. H. pylori infection may play a pathophysiologic role in NAFLD development, indicating that H. pylori eradication might play a role in reducing the risk of NAFLD.