title: Helicobacter pylori seropositivity's association with markers of iron, 1-carbon metabolism, and antioxidant status among US adults: a structural equations modeling approach.
abstract: OBJECTIVE
  We tested a model in which Helicobacter pylori seropositivity (Hps) predicted iron status, which in turn acted as a predictor for markers of 1-C metabolism that were then allowed to predict antioxidant status.
  
  
  METHODS
  National Health and Nutrition Examination Surveys (NHANES 1999-2000) cross-sectional data among adults aged 20-85 y were analyzed (n = 3,055). Markers of Hps, iron status (serum ferritin and transferrin saturation (TS)); 1-C metabolism (serum folate (FOLserum), B-12, total homocysteine (tHcy), methylmalonic acid (MMA)) and antioxidant status (vitamins A and E) were entered into a structural equations model (SEM).
  
  
  RESULTS
  Predictors of Hps included older age, lower education and income, racial/ethnic groups (lowest among Non-Hispanic Whites), and lifetime cigarette smoking. SEM modeling indicated that Hps had a direct inverse relationship with iron status (combining serum ferritin and TS) which in turn was positively related to 1-C metabolites (higher serum folate, B-12 or lower tHcy/MMA) that were positively associated with antioxidant status (combining serum vitamins A and E). Another pathway that was found bypassed 1-C metabolites (Hps → Iron_st → Antiox). The sum of all indirect effects from Hps combining both pathways and the other indirect pathways in the model (Hps → Iron_st → OneCarbon; Hps →OneCarbon →Antiox) was estimated at β = -0.006±0.003, p<0.05.
  
  
  CONCLUSIONS
  In sum, of the total effect of H. pylori seropositivity on antioxidant status, two significant indirect pathways through Iron status and 1-Carbon metabolites were found. Randomized controlled trials should be conducted to uncover the concomitant causal effect of H. pylori eradication on improving iron status, folate, B-12 and antioxidant status among H. pylori seropositive individuals.
authors: National Institute on Aging, NIA/NIH/IRP, Baltimore, Maryland, United States of America.
authors: May A
authors: MA
authors: Beydoun
authors: National Institute on Aging, NIA/NIH/IRP, Baltimore, Maryland, United States of America.
authors: Greg A
authors: GA
authors: Dore
authors: Pediatric Endocrinology, Diabetes and Metabolism Nemours Children's Clinic, Jacksonville, Florida, United States of America.
authors: Jose A
authors: JA
authors: Canas
authors: Graduate program in public health, Eastern Virginia Medical School, Norfolk, Virginia, United States of America.
authors: Hind A
authors: HA
authors: Beydoun
authors: National Institute on Aging, NIA/NIH/IRP, Baltimore, Maryland, United States of America.
authors: Alan B
authors: AB
authors: Zonderman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000975:Antioxidants / Q000378:metabolism*; D003430:Cross-Sectional Studies; D005260:Female; D005492:Folic Acid / Q000097:blood; D016481:Helicobacter Infections / Q000097:blood* / Q000382:microbiology; D016480:Helicobacter pylori / Q000302:isolation & purification / Q000378:metabolism* / Q000472:pathogenicity; D006801:Humans; D007501:Iron / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009749:Nutrition Surveys; D014481:United States; D014805:Vitamin B 12 / Q000097:blood
chemical_list: D000975:Antioxidants; D005492:Folic Acid; D007501:Iron; D014805:Vitamin B 12