Helicobacter pylori-associated chronic gastritis and unexplained iron deficiency anemia: a reliable association?

BACKGROUND AND AIM: About 35% of iron deficiency anemia cases remain unexplained after a gastrointestinal evaluation. An association between Helicobacter pylori and iron malabsorption has been suggested. The aim of this study was to determine whether H. pylori-associated chronic gastritis is linked to unexplained iron deficiency anemia in adults.
METHODS: From 1996 to 2001, we identified 105 patients with unexplained iron deficiency anemia after upper endoscopy, colonoscopy, small bowel radiographic examination and duodenal biopsies. Two biopsies were obtained from the gastric antrum and two from the corpus of each patient. Gastritis status was described according to the Sydney System and H. pylori infection was assessed by an immunohistochemical test on biopsy specimens. This group was compared to a control group matched for sex and age.
RESULTS: There were 76 women and 29 men (mean age 57.4 +/- 21.4 years) examined in the study. A H. pylori-associated chronic gastritis was identified in 63 cases (60%) vs. 45 cases (43%) cases in the control group (p <.01). Atrophic gastritis was significantly associated with iron deficiency anemia compared with the control group [16 (15%) vs. 6 (6%); p <.03]. In the unexplained iron deficiency anemia group, (1) patients with chronic gastritis were significantly younger (52 +/- 22 vs. 64 +/- 20 years; p <.005), and (2) chronic gastritis was not linked to sex [sex ratio (male/female): 0.5 vs. 0.34, p =.34]. The prevalence of H. pylori infection was similar between premenopausal and postmenopausal women [28 (27%) vs. 26 (25%); p =.7] with iron deficiency anemia.
CONCLUSION: H. pylori infection and chronic gastritis, especially atrophic gastritis, are significantly associated with unexplained iron deficiency anemia. Relationships between H. pylori-associated chronic gastritis and unexplained iron deficiency anemia should be considered.