title: Acid suppressive drugs and gastric cancer: a meta-analysis of observational studies.
abstract: OBJECTIVE
  To evaluate the association between acid suppressive drug use and the development of gastric cancer.
  
  
  METHODS
  A systematic search of relevant studies that were published through June 2012 was conducted using the MEDLINE (PubMed), EMBASE, and Cochrane Library databases. The search included observational studies on the use of histamine 2-receptor antagonists (H₂RAs) or proton pump inhibitors and the associated risk of gastric cancer, which was measured using the adjusted odds ratio (OR) or the relative risk and 95%CI. An independent extraction was performed by two of the authors, and a consensus was reached.
  
  
  RESULTS
  Of 4595 screened articles, 11 observational studies (n = 94558) with 5980 gastric cancer patients were included in the final analyses. When all the studies were pooled, acid suppressive drug use was associated with an increased risk of gastric cancer risk (adjusted OR = 1.42; 95%CI: 1.29-1.56, I² = 48.9%, P = 0.034). The overall risk of gastric cancer increased among H₂RA users (adjusted OR = 1.40; 95%CI: 1.24-1.59, I² = 59.5%, P = 0.008) and PPI users (adjusted OR = 1.39; 95%CI: 1.19-1.64, I² = 0.0%, P = 0.377).
  
  
  CONCLUSIONS
  Acid suppressive drugs are associated with an increased risk of gastric cancer. Further studies are needed to test the effect of acid suppressive drugs on gastric cancer.
authors.affiliation: Department of Family Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul 110-744, South Korea.
authors.forename: Jeong Soo
authors.initials: JS
authors.lastname: Ahn
authors.forename: Chun-Sick
authors.initials: CS
authors.lastname: Eom
authors.forename: Christie Y
authors.initials: CY
authors.lastname: Jeon
authors.forename: Sang Min
authors.initials: SM
authors.lastname: Park
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006635:Histamine H2 Antagonists / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D054328:Proton Pump Inhibitors / Q000009:adverse effects*; D018570:Risk Assessment; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000139:chemically induced*; D055815:Young Adult
chemical_list: D006635:Histamine H2 Antagonists; D054328:Proton Pump Inhibitors
keywords: Gastric cancer; H2-receptor antagonists; Meta-analysis; Proton pump inhibitors