title: Leptin and the risk of Barrett's oesophagus.
abstract: BACKGROUND
  Obesity is associated with increased risks of Barrett's oesophagus and oesophageal adenocarcinoma. Alterations in serum leptin and adiponectin, obesity-related cytokines, have been linked with several cancers and have been postulated as potential mediators of obesity-related carcinogenesis; however, the relationship with Barrett's oesophagus remains unexplored.
  
  
  METHODS
  Serum leptin and adiponectin concentrations were measured on two subsets of participants within a case-control study conducted in Brisbane, Australia. Cases were people aged 18-79 years with histologically confirmed Barrett's oesophagus newly diagnosed between 2003 and 2006. Population controls, frequency matched by age and sex to cases, were randomly selected from the electoral roll. Phenotype and medical history data were collected through structured, self-completed questionnaires. Odds ratios (OR) and 95% CI were calculated using multivariable logistic regression analysis.
  
  
  RESULTS
  In the pilot analysis (51 cases, 67 controls) risks of Barrett's oesophagus were highest among those in the highest quartile of serum leptin (OR 4.6, 95% CI 0.6 to 33.4). No association was seen with adiponectin. In the leptin validation study (306 cases, 309 controls), there was a significant threefold increased risk of Barrett's oesophagus among men in the highest quartile of serum leptin (OR 3.3, 95% CI 1.7 to 6.6) and this persisted after further adjustment for symptoms of gastro-oesophageal reflux (OR 2.4, 95% CI 1.1 to 5.2). In contrast, the risk of Barrett's oesophagus among women decreased with increasing serum leptin concentrations.
  
  
  CONCLUSIONS
  High serum leptin is associated with an increased risk of Barrett's oesophagus among men but not women. This association is not explained simply by higher body mass or gastro-oesophageal reflux among cases. The mechanism remains to be determined.
authors.affiliation: Division of Population Studies and Human Genetics, Queensland Institute of Medical Research, Brisbane, Australia.
authors.forename: B J
authors.initials: BJ
authors.lastname: Kendall
authors.forename: G A
authors.initials: GA
authors.lastname: Macdonald
authors.forename: N K
authors.initials: NK
authors.lastname: Hayward
authors.forename: J B
authors.initials: JB
authors.lastname: Prins
authors.forename: I
authors.initials: I
authors.lastname: Brown
authors.forename: N
authors.initials: N
authors.lastname: Walker
authors.forename: N
authors.initials: N
authors.lastname: Pandeya
authors.forename: A C
authors.initials: AC
authors.lastname: Green
authors.forename: P M
authors.initials: PM
authors.lastname: Webb
authors.forename: D C
authors.initials: DC
authors.lastname: Whiteman
mesh_terms: D052242:Adiponectin / Q000097:blood; D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D001471:Barrett Esophagus / Q000097:blood* / Q000209:etiology; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D005260:Female; D005764:Gastroesophageal Reflux / Q000097:blood / Q000150:complications; D006801:Humans; D020738:Leptin / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D017678:Sex Distribution; D012737:Sex Factors
chemical_list: D052242:Adiponectin; D015415:Biomarkers; D020738:Leptin