title: Proximal and distal gastro-oesophageal reflux in chronic obstructive pulmonary disease and bronchiectasis.
abstract: OBJECTIVE
  The aims of this observational study were (i) to examine the prevalence of symptomatic and clinically silent proximal and distal gastro-oesophageal reflux (GOR) in adults with chronic obstructive pulmonary disease (COPD) or bronchiectasis, (ii) the presence of gastric aspiration, and (iii) to explore the possible clinical significance of this comorbidity in these conditions.
  
  
  METHODS
  Twenty-seven participants with COPD, 27 with bronchiectasis and 17 control subjects completed reflux symptom evaluation and dual-channel 24 h oesophageal pH monitoring. In those with lung disease, pepsin levels in sputum samples were measured using enzyme-linked immunosorbent assay, with disease severity (lung function and high-resolution computed tomography) also measured.
  
  
  RESULTS
  The prevalence of GOR in COPD was 37%, in bronchiectasis was 40% and in control subjects was 18% (P = 0.005). Of those diagnosed with GOR, clinically silent reflux was detected in 20% of participants with COPD and 42% with bronchiectasis. While pepsin was found in 33% of COPD and 26% of bronchiectasis participants, the presence of pepsin in sputum was not related to a diagnosis of GOR based on oesophageal pH monitoring in either condition. Neither a diagnosis of GOR nor the presence of pepsin was associated with increased severity of lung disease in COPD or bronchiectasis.
  
  
  CONCLUSIONS
  The prevalence of GOR in COPD or bronchiectasis is twice that of the control population, and the diagnosis could not be based on symptoms alone. Pepsin was detected in sputum in COPD and bronchiectasis, suggesting a possible role of pulmonary aspiration, which requires further exploration.
authors.affiliation: Physiotherapy, Melbourne School of Health Sciences, University of Melbourne, Melbourne, Victoria, Australia.|Department of Physiotherapy, The Alfred, Melbourne, Victoria, Australia.
authors.forename: Annemarie L
authors.initials: AL
authors.lastname: Lee
authors.affiliation: Department of Physiotherapy, The Alfred, Melbourne, Victoria, Australia.|Department of Medicine, Monash University, Melbourne, Victoria, Australia.|Department of Allergy, Immunology and Respiratory Medicine, The Alfred Hospital, Melbourne, Victoria, Australia.
authors.forename: Brenda M
authors.initials: BM
authors.lastname: Button
authors.affiliation: Physiotherapy, Melbourne School of Health Sciences, University of Melbourne, Melbourne, Victoria, Australia.
authors.forename: Linda
authors.initials: L
authors.lastname: Denehy
authors.affiliation: Department of Gastroenterology, The Alfred, Melbourne, Victoria, Australia.|Department of Medicine, Monash University, Melbourne, Victoria, Australia.
authors.forename: Stuart J
authors.initials: SJ
authors.lastname: Roberts
authors.affiliation: Department of Medicine, Monash University, Melbourne, Victoria, Australia.|Janssen, Pharmaceutical Companies of Johnson and Johnson, Melbourne, Victoria, Australia.
authors.forename: Tiffany L
authors.initials: TL
authors.lastname: Bamford
authors.affiliation: Department of Radiology, The Alfred, Melbourne, Victoria, Australia.
authors.forename: Samantha J
authors.initials: SJ
authors.lastname: Ellis
authors.affiliation: Department of Immunology, Monash University, Melbourne, Victoria, Australia.
authors.forename: Fi-Tjen
authors.initials: FT
authors.lastname: Mu
authors.affiliation: Murdoch Children's Research Institute, University of Melbourne, Melbourne, Victoria, Australia.|Department of Gastroenterology and Clinical Nutrition, Royal Children's Hospital, Melbourne, Victoria, Australia.
authors.forename: Ralf G
authors.initials: RG
authors.lastname: Heine
authors.affiliation: Department of Medicine, Monash University, Melbourne, Victoria, Australia.|Department of Allergy, Immunology and Respiratory Medicine, The Alfred Hospital, Melbourne, Victoria, Australia.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Stirling
authors.affiliation: Department of Medicine, Monash University, Melbourne, Victoria, Australia.|Department of Allergy, Immunology and Respiratory Medicine, The Alfred Hospital, Melbourne, Victoria, Australia.
authors.forename: John W
authors.initials: JW
authors.lastname: Wilson
mesh_terms: D000328:Adult; D000368:Aged; D001987:Bronchiectasis / Q000150:complications* / Q000175:diagnosis; D050782:Esophageal pH Monitoring; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000175:diagnosis
keywords: bronchiectasis; chronic obstructive pulmonary disease; gastro-oesophageal reflux; quality of life