title: A reduction in the use of volunteered descriptors of air hunger is associated with increased walking distance in people with COPD.
abstract: BACKGROUND
  This study investigated whether descriptors of breathlessness differed after participation in an 8 week pulmonary rehabilitation program and whether changes in sensory quality would be reflected in responsiveness to pulmonary rehabilitation.
  
  
  METHODS
  People with COPD provided  descriptors for their sensation of breathlessness before and after an 8 week pulmonary rehabilitation program. Primary outcomes for responsiveness to pulmonary rehabilitation were the 6 minute walk distance (6MWD) and the St George Respiratory questionnaire. Significant proportional shifts  for sensory categories after rehabilitation were identified using the McNemar test. Random effects mixed modeling was used to determine significance of differences for primary outcomes between subjects modifying or not modifying descriptors of breathlessness.
  
  
  RESULTS
  Of the 107 people referred  to the pulmonary rehabilitation program, 94 met the spirometric criteria for COPD, with 58 having data for pre and post assessments (36 males, 71 ± 9 years old, percent of predicted FEV(1) 58 ± 24%). A significant proportion of subjects reduced descriptors of air  hunger (P = .03, odds ratio 0.31, 95% CI 0.09-0.89) and depressed, regret, helpless (P = .04, odds ratio 0.36, 95% CI 0.10-1.05) following rehabilitation. Subjects reducing their use of descriptors of air hunger had greater improvements in the 6MWD after  rehabilitation (P = .006, mean increase 46 m).
  
  
  CONCLUSIONS
  The sensory quality of breathlessness was modified for approximately one third of subjects after pulmonary rehabilitation, with significant improvements in the 6MWD for subjects who reduced their use of descriptors of air hunger.
authors.affiliation: School of Health Sciences, University of South Australia, Adelaide, South Australia, Australia. marie.williams@unisa.edu.au
authors.forename: Marie T
authors.initials: MT
authors.lastname: Williams
authors.forename: John
authors.initials: J
authors.lastname: Petkov
authors.forename: Timothy S
authors.initials: TS
authors.lastname: Olds
authors.forename: Paul
authors.initials: P
authors.lastname: Cafarella
authors.forename: Peter
authors.initials: P
authors.lastname: Frith
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D004417:Dyspnea / Q000503:physiopathology / Q000523:psychology*; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D007802:Language; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology / Q000523:psychology* / Q000534:rehabilitation; D012677:Sensation; D011795:Surveys and Questionnaires; D014705:Verbal Behavior; D016138:Walking / Q000502:physiology*