title: Short term micronutrient-antioxidant supplementation has no impact on a serological marker of gastric atrophy in Zambian adults: retrospective analysis of a randomised controlled trial.
abstract: BACKGROUND
  Gastric cancer is a major contributor to cancer deaths in Zambia but, as elsewhere, no preventive strategies have been identified. We set out to investigate the possibility of reducing gastric atrophy, a premalignant lesion, using micronutrient-antioxidant supplementation.
  
  
  METHODS
  We analysed 215 archival samples from a randomised controlled trial of micronutrient-antioxidant supplementation carried out from 2003 to 2006. Participants were randomised to receive either the supplement or placebo and had been taking the allocated intervention for a mean of 18 (range 14-27) months when the samples used in this study were taken. We used low pepsinogen 1 to 2 (PEP1:2) ratio as a surrogate marker of gastric atrophy. A PEP 1:2 ratio of less than three was considered low. HIV serology, age, nutritional status, smoking, alcohol intake and gastric pH were also analysed. Ethical approval was obtained from the University of Zambia Biomedical Research Ethics Committee (011-04-12). The randomized trial was registered (ISRCTN31173864).
  
  
  RESULTS
  The overall prevalence of low PEP 1:2 ratio was 15/215 (7%) and it did not differ between the placebo (8/103, 7.8%) and micronutrient groups (7/112, 6.3%; HR 1.24; 95% CI 0.47-3.3; P = 0.79). The presence of low PEP 1:2 ratio was not influenced by HIV infection (HR 1.07; 95% CI 0.37-3.2; P =0.89) or nutritional status but it inversely correlated with gastric pH (Spearman's rho = -0.34; P = 0.0001). Age above 40 years was associated with atrophy, but neither alcohol nor smoking had any influence.
  
  
  CONCLUSIONS
  Short term micronutrient supplementation does not have any impact on PEP 1:2 ratio, a serological marker of gastric atrophy. PEP 1:2 ratio inversely correlates with gastric pH.
authors.affiliation: Department of Internal Medicine, Tropical Gastroenterology & Nutrition group, University of Zambia School of Medicine, Nationalist Road, Lusaka, Zambia. viojole@yahoo.com.
authors.forename: Violet
authors.initials: V
authors.lastname: Kayamba
authors.forename: Mumba
authors.initials: M
authors.lastname: Chomba
authors.forename: Paul
authors.initials: P
authors.lastname: Kelly
mesh_terms: D000328:Adult; D000367:Age Factors; D000975:Antioxidants / Q000008:administration & dosage*; D001284:Atrophy / Q000097:blood / Q000188:drug therapy; D015415:Biomarkers / Q000097:blood; D019587:Dietary Supplements; D005260:Female; D005750:Gastric Juice / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D018977:Micronutrients / Q000008:administration & dosage*; D008875:Middle Aged; D020116:Pepsinogen A / Q000097:blood; D020115:Pepsinogen C / Q000097:blood; D012189:Retrospective Studies; D013270:Stomach / Q000473:pathology*; D013272:Stomach Diseases / Q000097:blood* / Q000188:drug therapy; D013997:Time Factors; D055815:Young Adult; D015024:Zambia
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D018977:Micronutrients; D020115:Pepsinogen C; D020116:Pepsinogen A