Helicobacter pylori infection and serum ferritin: A population-based study among 1806 adults in Germany.

ABSTRACT

OBJECTIVE: Helicobacter pylori may possibly affect the iron metabolism by occult bleeding, impaired absorption of non-hem iron, and by scavenging hem iron or ferritin, as some studies have suggested. The aim of this study was to analyze the association between H. pylori infection and serum ferritin, a marker of the body iron stores. In this analysis, we paid particular attention to the role of dietary iron intake and CagA, an established virulence factor of the agent. METHODS: The analysis is based on a cross-sectional national health and nutrition survey among healthy people in Germany conducted in 1987/1988. The examination included a detailed questionnaire on medical history and lifestyle factors, a 7-day food record, and blood samples. Infection with H. pylori was measured serologically by ELISA and Westernblot. RESULTS: In total, 39.2% of 1806 persons aged 18 to 89 yr included in the study were H. pylori positive, of whom 57.6% had an infection with a CagA-positive H. pylori strain. Age- and sex-adjusted geometric mean of ferritin was 54.5 microg/dl among H. pylori-infected compared with 63.8 microg/dl among uninfected persons. A multiple linear regression model with log-transformed serum ferritin concentration as dependent variable and H. pylori infection and several potential confounding factors as independent variable was fitted. In this model, H. pylori infection was associated with a 17.0% decrease of the serum ferritin concentration (95% CI = 9.8-23.6). The association between H. pylori infection and serum ferritin levels did not vary by gender, age, and iron intake, and it was similar for CagA-positive and CagA-negative H. pylori infections. CONCLUSIONS: The decreased serum ferritin concentration among subjects infected with H. pylori might be induced by the uptake of ferritin in the stomach by H. pylori. Possible health implications of H. pylori-induced low ferritin levels warrant further investigation.