title: Dyspnea affective response: comparing COPD patients with healthy volunteers and laboratory model with activities of daily living.
abstract: BACKGROUND
  Laboratory-induced dyspnea (breathing discomfort) in healthy subjects is widely used to study perceptual mechanisms, yet the relationship between laboratory-induced dyspnea in healthy volunteers and spontaneous dyspnea in patients with chronic lung disease is not well established. We compared affective responses to dyspnea 1) in COPD patients vs. healthy volunteers (HV) undergoing the same laboratory stimulus; 2) in COPD during laboratory dyspnea vs. during activities of daily living (ADL).
  
  
  METHODS
  We induced moderate and high dyspnea levels in 13 COPD patients and 12 HV by increasing end-tidal CO2 (PETCO2) during restricted ventilation, evoking air hunger. We used the multidimensional dyspnea profile (MDP) to measure intensity of sensory qualities (e.g., air hunger (AH) and work/effort (W/E)) as well as immediate discomfort (A1) and secondary emotions (A2). Ten of the COPD subjects also completed the MDP outside the laboratory following dyspnea evoked by ADL.
  
  
  RESULTS
  COPD patients and HV reported similar levels of immediate discomfort relative to sensory intensity. COPD patients and HV reported anxiety and frustration during laboratory-induced dyspnea; variation among individuals far outweighed the small differences between subject groups. COPD patients reported similar intensities of sensory qualities, discomfort, and emotions during ADL vs. during moderate laboratory dyspnea. Patients with COPD described limiting ADL to avoid greater dyspnea.
  
  
  CONCLUSIONS
  In this pilot study, we found no evidence that a history of COPD alters the affective response to laboratory-induced dyspnea, and no difference in affective response between dyspnea evoked by this laboratory model and dyspnea evoked by ADL.
authors.affiliation: Division of Pulmonary, Critical Care, and Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA, 02215, USA. codonne1@bidmc.harvard.edu
authors.forename: Carl R
authors.initials: CR
authors.lastname: O'Donnell
authors.forename: Richard M
authors.initials: RM
authors.lastname: Schwartzstein
authors.forename: Robert W
authors.initials: RW
authors.lastname: Lansing
authors.forename: Tegan
authors.initials: T
authors.lastname: Guilfoyle
authors.forename: Daniel
authors.initials: D
authors.lastname: Elkin
authors.forename: Robert B
authors.initials: RB
authors.lastname: Banzett
mesh_terms: D000203:Activities of Daily Living / Q000523:psychology*; D000368:Aged; D000369:Aged, 80 and over; D001007:Anxiety / Q000453:epidemiology; D002245:Carbon Dioxide / Q000009:adverse effects; D016022:Case-Control Studies; D004417:Dyspnea / Q000139:chemically induced / Q000523:psychology*; D004644:Emotions; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D029424:Pulmonary Disease, Chronic Obstructive / Q000523:psychology*; D013990:Tidal Volume
chemical_list: D002245:Carbon Dioxide