title: Determinants of health-related quality of life in patients with pulmonary emphysema.
abstract: OBJECTIVE
  The aim of our study was to examine the relationship between health-related quality of life (HRQL), lung function parameters and intensity of dyspnea in order to determinate what variables influence the HRQL in patients with pulmonary emphysema.
  
  
  METHODS
  Forty (mean aged 66+/-9) consecutive male patients with pulmonary emphysema were evaluated. All patients underwent spirometry, measurement of lung volumes, inspiratory and expiratory respiratory pressure (MIP and MEP), measurement of corrected carbon monoxide diffusing capacity (KCO), and 6-min walking test (6MWT). The scale of dyspnea by the baseline dyspnea index (BDI) and British Medical Council Research (MCR), and the quality of life by Chronic Respiratory Question Disease (CRQD) were also assessed.
  
  
  RESULTS
  FEV1, FVC, 6MWT, KCO, MEP, MIP, BDI and MCR were correlated with dimensions of CRQD. Factor analysis reduced these variables to four factors, which accounted for 86.2% of the total variance: (1) airway obstruction, (2) dyspnea, (3) capacity of effort, (4) maximum static respiratory pressure. In the multiple regression model BDI and MEP explained the 64% of the total variance of CRQD.
  
  
  CONCLUSIONS
  Quality of life measured by CRQD in patients with emphysema is predominantly determined by dyspnea, and in minor degree by expiratory muscle strength. Our results underscore the usefulness of dyspnea scales and MEP in the evaluation of HRQL in patients with emphysema.
authors.affiliation: Department of Pneumology, Dr. Peset University Hospital, Maestro Valls 46, Pta 21, 46022 Valencia, Valencia, Spain. edgonc@ono.com
authors.forename: Eduardo
authors.initials: E
authors.lastname: González
authors.forename: Alberto
authors.initials: A
authors.lastname: Herrejón
authors.forename: Ignacio
authors.initials: I
authors.lastname: Inchaurraga
authors.forename: Rafael
authors.initials: R
authors.lastname: Blanquer
mesh_terms: D000368:Aged; D004417:Dyspnea / Q000503:physiopathology; D005080:Exercise Test; D006304:Health Status; D006801:Humans; D008168:Lung / Q000503:physiopathology; D008176:Lung Volume Measurements; D008297:Male; D008875:Middle Aged; D011656:Pulmonary Emphysema / Q000503:physiopathology*; D011659:Pulmonary Gas Exchange; D011788:Quality of Life; D012129:Respiratory Function Tests