title: Symptomatic oxygen for non-hypoxaemic chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Dyspnoea is a common symptom in chronic obstructive pulmonary disease (COPD). People who are hypoxaemic may be given long-term oxygen relief therapy (LTOT) to improve their life expectancy and quality of life. However, the symptomatic benefit of home oxygen therapy in mildly or non-hypoxaemic people with COPD with dyspnoea who do not meet international funding criteria for LTOT (PaO(2)< 55 mmHg or other special cases) is unknown.
  
  
  OBJECTIVE
  To determine the efficacy of oxygen versus medical air for relief of subjective dyspnoea in mildly or non-hypoxaemic people with COPD who would not otherwise qualify for home oxygen therapy. The main outcome was patient-reported dyspnoea and secondary outcome was exercise tolerance.
  
  
  METHODS
  We searched the Cochrane Airways Group Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE, to November 2009, to identify randomised controlled trials. We handsearched reference lists of included articles.
  
  
  METHODS
  We only included randomised controlled trials of oxygen versus medical air in mildly or non-hypoxaemic people with COPD. Two review authors independently assessed articles for inclusion.
  
  
  METHODS
  One review author completed data extraction and methodological quality assessment. A second review author then over-read evidence tables to assess for accuracy.
  
  
  RESULTS
  Twenty-eight trials on 702 patients met the criteria for inclusion; 18 trials (431 participants) were included in the meta-analysis. Oxygen reduced dyspnoea with a standardised mean difference (SMD) of -0.37 (95% confidence interval (CI) -0.50 to -0.24, P < 0.00001). We observed significant heterogeneity.
  
  
  CONCLUSIONS
  Oxygen can relieve dyspnoea in mildly and non-hypoxaemic people with COPD who would not otherwise qualify for home oxygen therapy. Given the significant heterogeneity among the included studies, clinicians should continue to evaluate patients on an individual basis until supporting data from ongoing, large randomised controlled trials are available.
authors.affiliation: Division of Medical Oncology, Department of Medicine, Duke University Medical Center, Box 3841, Durham, NC, USA, 27710.
authors.forename: Hope
authors.initials: H
authors.lastname: Uronis
authors.forename: Douglas C
authors.initials: DC
authors.lastname: McCrory
authors.forename: Gregory
authors.initials: G
authors.lastname: Samsa
authors.forename: David
authors.initials: D
authors.lastname: Currow
authors.forename: Amy
authors.initials: A
authors.lastname: Abernethy
mesh_terms: D004417:Dyspnea / Q000209:etiology / Q000628:therapy*; D006699:Home Care Services; D006801:Humans; D010102:Oxygen Inhalation Therapy / Q000379:methods*; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications / Q000628:therapy*; D016032:Randomized Controlled Trials as Topic