title: Risk of Barrett's oesophagus, oesophageal adenocarcinoma and reflux oesophagitis and the use of nitrates and asthma medications.
abstract: OBJECTIVE
  To investigate the relationship between use of asthma medication and nitrates and risk of reflux oesophagitis, Barrett's oesophagus and oesophageal adenocarcinoma.
  
  
  METHODS
  Data were collected on use of asthma medication and nitrates at least 1 year before interview from patients with reflux oesophagitis, Barrett's oesophagus and oesophageal adenocarcinoma. Associations between use of asthma medications and nitrates and the risk of reflux oesophagitis, Barrett's oesophagus and oesophageal adenocarcinoma were estimated using multiple logistic regression.
  
  
  RESULTS
  Nine hundred and forty-one subjects were recruited: 230 reflux oesophagitis, 224 Barrett's oesophagus, 227 oesophageal adenocarcinoma patients and 260 population controls. Barrett's oesophagus patients were more likely than controls to have had a diagnosis of asthma (odds ratio 2.15, 95% confidence interval 1.15-4.03) and to have used asthma medications (odds ratio 2.13, 95% confidence interval 1.09-4.16). No significant associations were observed between use of asthma medication or nitrates and reflux oesophagitis or oesophageal adenocarcinoma.
  
  
  CONCLUSIONS
  Gastro-oesophageal reflux symptoms appear to confound the association between asthma medication use and Barrett's oesophagus. However, it is possible that asthma medications may increase the risk of Barrett's oesophagus by other mechanisms.
authors.affiliation: Centre for Public Health, Queen's University, and Royal Group of Hospitals, Belfast, Northern Ireland, UK.
authors.forename: Todd C
authors.initials: TC
authors.lastname: Ladanchuk
authors.forename: Brian T
authors.initials: BT
authors.lastname: Johnston
authors.forename: Liam J
authors.initials: LJ
authors.lastname: Murray
authors.forename: Lesley A
authors.initials: LA
authors.lastname: Anderson
mesh_terms: D000230:Adenocarcinoma / Q000139:chemically induced*; D000368:Aged; D018927:Anti-Asthmatic Agents / Q000009:adverse effects*; D001471:Barrett Esophagus / Q000139:chemically induced*; D016022:Case-Control Studies; D004938:Esophageal Neoplasms / Q000139:chemically induced*; D004942:Esophagitis, Peptic / Q000139:chemically induced*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000009:adverse effects*; D012307:Risk Factors
chemical_list: D018927:Anti-Asthmatic Agents; D009566:Nitrates