Serum ferritin, hemoglobin, and Helicobacter pylori infection: a seroepidemiologic survey comprising 2794 Danish adults.

BACKGROUND & AIMS Helicobacter pylori infection was recently associated with iron-deficiency anemia. The aim of this study was to examine the relationship between H. pylori infection, hemoglobin, and iron status using serum ferritin as a marker for total body iron. METHODS Serum ferritin, hemoglobin, and immunoglobulin G (IgG) antibodies against H. pylori were assessed in 2794 Danish adults who attended a population survey. IgG antibodies were measured with an in-house enzyme-linked immunosorbent assay, serum ferritin with an immunoradiometric assay, and hemoglobin with Coulter-S. RESULTS The seroprevalence of H. pylori infection did not relate to hemoglobin. Serum ferritin levels were significantly lower in men (114 vs. 120 microg/L; P = 0.01) and in postmenopausal women (63 vs. 77 microg/L; P = 0.02) who were IgG positive than in seronegative individuals. IgG-positive people more often had reduced serum ferritin levels (</=30 microg/L) than seronegative people. This association persisted in multivariate analysis after adjusting for possible confounding factors (odds ratio, 1.4; 95% confidence interval 1.1-1. 8). CONCLUSIONS Serum ferritin levels are reduced in people with increased IgG antibodies to H. pylori. H. pylori infection affects iron metabolism in humans.