title: Treatment of Sleep Disordered Breathing Liberates Obese Hypoxemic Patients from Oxygen.
abstract: BACKGROUND
  Obese hypoxemic patients have a high prevalence of sleep disordered breathing (SDB). It is unclear to what extent treatment of SDB can improve daytime hypoxemia.
  
  
  METHODS
  We performed a retrospective cohort study of obese hypoxemic individuals, all of whom underwent polysomnography, arterial blood gas analysis, and subsequent initiation of positive airway pressure (PAP) therapy for SDB. Patients were followed for one year for change in partial pressure of arterial oxygen and the need for supplemental oxygen.
  
  
  RESULTS
  One hundred and seventeen patients were treated with nocturnal PAP and had follow-up available. Adherence to PAP was satisfactory in 60%, and was associated with a significant improvement in daytime hypoxemia and hypercapnea; 56% of these patients were able to discontinue supplemental oxygen. Adherence to PAP therapy and the baseline severity of OSA predicted improvement in hypoxemia, but only adherence to PAP therapy predicted liberation from supplemental oxygen.
  
  
  CONCLUSIONS
  The identification and treatment of SDB in obese hypoxemic patients improves daytime hypoxemia. It is important to identify SDB in these patients, since supplemental oxygen can frequently be discontinued following treatment with PAP therapy.
authors.affiliation: Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada; Department of Medicine, Western University, London, Ontario, Canada.
authors.forename: Marcus
authors.initials: M
authors.lastname: Povitz
authors.affiliation: Department of Medicine, University of Calgary, Calgary, Alberta, Canada; Sleep Centre, Foothills Medical Centre, Calgary, Alberta, Canada.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Hanly
authors.affiliation: Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada; Department of Medicine, University of Calgary, Calgary, Alberta, Canada; Sleep Centre, Foothills Medical Centre, Calgary, Alberta, Canada.
authors.forename: Sachin R
authors.initials: SR
authors.lastname: Pendharkar
authors.affiliation: Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada; Department of Medicine, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Matthew T
authors.initials: MT
authors.lastname: James
authors.affiliation: Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada; Department of Medicine, University of Calgary, Calgary, Alberta, Canada; Sleep Centre, Foothills Medical Centre, Calgary, Alberta, Canada.
authors.forename: Willis H
authors.initials: WH
authors.lastname: Tsai
mesh_terms: D000368:Aged; D001158:Arteries / Q000737:chemistry; D015331:Cohort Studies; D003131:Combined Modality Therapy; D045422:Continuous Positive Airway Pressure; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000097:blood / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000628:therapy*; D010100:Oxygen / Q000097:blood / Q000627:therapeutic use*; D017286:Polysomnography; D011659:Pulmonary Gas Exchange; D012189:Retrospective Studies; D012891:Sleep Apnea Syndromes / Q000097:blood / Q000628:therapy*
chemical_list: D010100:Oxygen