title: An updated systematic review and meta-analysis on the association between Helicobacter pylori infection and iron deficiency anemia.
abstract: BACKGROUND
  We conducted an updated systematic review and meta-analysis to examine the prevalence of depleted iron stores among persons infected with Helicobacter pylori compared to uninfected ones. We also assessed the impact of anti-H. pylori eradication therapy plus iron therapy on ferritin and hemoglobin levels compared to iron therapy alone.
  
  
  METHODS
  A literature search was conducted using the databases Medline, the Cochrane Library, Cochrane Central Register of Controlled Trials, EMBASE, and the Science Citation Index Expanded. Observational studies with methodological quality score of 13 (median score) and above, on a scale of 0-16, and all randomized controlled trials (RCTs) were eligible for the meta-analyses. Pooled point estimates and 95% confidence intervals (CI) were obtained using the random effects model.
  
  
  RESULTS
  Compared to uninfected persons, H. pylori-infected individuals showed increased likelihood of iron deficiency anemia (14 observational studies); pooled OR 1.72 (95% CI 1.23-2.42); iron deficiency (pooled OR 1.33; 95% CI 1.15-1.54; 30 studies); and anemia (pooled OR 1.15; 95% CI 1.00-1.32; 23 studies). Meta-analyses of seven RCTs showed increased ferritin, standardized mean difference (SMD) 0.53 (95% 0.21-0.85), but not hemoglobin, SMD 0.36 (95% -0.07 to 0.78), Pv=.1, following anti-H. pylori eradication therapy plus iron therapy as compared with iron therapy alone. Significant heterogeneity was found among studies, as well as evidence of publication bias.
  
  
  CONCLUSIONS
  Current evidence indicates increased likelihood of depleted iron stores in relation to H. pylori infection. H. pylori eradication therapy, added to iron therapy, might be beneficial in increasing ferritin and hemoglobin levels.
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Lauren
authors.initials: L
authors.lastname: Hudak
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Ameen
authors.initials: A
authors.lastname: Jaraisy
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Saeda
authors.initials: S
authors.lastname: Haj
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Khitam
authors.initials: K
authors.lastname: Muhsen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018798:Anemia, Iron-Deficiency / Q000209:etiology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D016481:Helicobacter Infections / Q000150:complications*; D006801:Humans; D007223:Infant; D008875:Middle Aged; D011247:Pregnancy; D055815:Young Adult
keywords: Helicobacter pylori infection; clinical trials; iron deficiency anemia; meta-analysis; observational studies; systematic review