title: Obstructive sleep apnoea and nocturnal gastroesophageal reflux are common in lung transplant patients.
abstract: OBJECTIVE
  Gastroesophageal reflux (GOR) has been implicated in the pathogenesis of bronchiolitis obliterans syndrome (BOS), possibly due to pulmonary aspiration of refluxed acid. Risk of aspiration of gastric contents is increased during sleep due to decreased oesophageal clearance mechanisms and may be further increased by the presence of OSA. This study investigated the relationship between nocturnal GOR, OSA and BOS in a group of lung transplant patients.
  
  
  METHODS
  Fourteen lung transplant patients underwent overnight polysomnography with simultaneous dual oesophageal pH monitoring.
  
  
  RESULTS
  Patients had an FEV(1) of 84 +/- 15% of their best post-transplant FEV(1). Six of the 14 patients were in various stages of BOS. The average proportion of time spent overnight with a pH of <4 was 1.7 +/- 3.1%. Increased GOR was evident in 8/14 patients during the postprandial period and/or overnight in the distal and/or proximal oesophagus. All patients had OSA (AHI >5 events per hour). There were no relationships between severity of OSA or GOR and severity of BOS.
  
  
  CONCLUSIONS
  Both nocturnal GOR and OSA were common in this group of patients but their occurrences were not related. Neither was there any relationship between the presence of nocturnal GOR or OSA and severity of BOS.
authors.affiliation: Department of Pulmonary Physiology, West Australian Sleep Disorders Research Institute, Sir Charles Gairdner Hospital, Nedlands, WA, Australia.
authors.forename: Kelly L
authors.initials: KL
authors.lastname: Shepherd
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Chambers
authors.forename: Eli
authors.initials: E
authors.lastname: Gabbay
authors.forename: David R
authors.initials: DR
authors.lastname: Hillman
authors.forename: Peter R
authors.initials: PR
authors.lastname: Eastwood
mesh_terms: D000368:Aged; D001989:Bronchiolitis Obliterans / Q000601:surgery; D002940:Circadian Rhythm / Q000502:physiology*; D003680:Deglutition Disorders / Q000150:complications* / Q000453:epidemiology / Q000503:physiopathology; D050782:Esophageal pH Monitoring; D004947:Esophagus / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D005764:Gastroesophageal Reflux / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D005769:Gastrointestinal Motility / Q000502:physiology; D006801:Humans; D016040:Lung Transplantation / Q000502:physiology*; D008297:Male; D008365:Manometry; D008875:Middle Aged; D017286:Polysomnography; D015995:Prevalence; D011379:Prognosis; D012307:Risk Factors; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology