title: Longitudinal changes in patient-reported dyspnea in patients with COPD.
abstract: BACKGROUND
  Although guidelines recommend monitoring symptoms in patients with chronic obstructive pulmonary disease (COPD), there is limited information on the longitudinal changes in patient-reported dyspnea (PRD) related to activities of daily living. The hypothesis was that PRD scores on the modified Medical Research Council (mMRC) scale, the self-administered computerized (SAC) transition dyspnea index (TDI), and the University of California San Diego Shortness of Breath questionnaire (UCSD SOBQ) would demonstrate progression over two years.
  
  
  METHODS
  Observational cohort study of symptomatic patients with stable COPD evaluated every 6 months for 2 years. Patients rated the impact of activities of daily living on dyspnea using three patient-reported instruments presented in random order, and then performed post-bronchodilator (pBD) spirometry.
  
  
  RESULTS
  Seventy patients (37 female/33 male; age: 66 ± 9 years; and pBD forced expiratory volume in one second [(FEV1): 51 ± 16% predicted] participated. Using fixed effects regression modeling, there was significant worsening in the PRD scores with the SAC TDI (-0.9 ± 2.7; p = 0.03) and UCSD SOBQ (+5.7 ± 18.3; p = 0.001), but not with the mMRC scale (p = 0.52). Both pBD FEV1 (p = 0.19) and pBD forced vital capacity (p = 0.65) were unchanged.
  
  
  CONCLUSIONS
  Multidimensional instruments (SAC TDI and UCSD SOBQ) demonstrated the frequently observed decline in PRD experienced by patients with COPD. The progression in PRD occurred despite stable lung function. Monitoring PRD provides unique clinical information and should be considered along with measuring lung function to assess patient status over time.
authors.affiliation: Section of Pulmonary & Critical Care Medicine, Geisel School of Medicine at Dartmouth, Hanover, NH 03756-0001, USA. Donald.a.mahler@hitchcock.org
authors.forename: Donald A
authors.initials: DA
authors.lastname: Mahler
authors.forename: Joseph
authors.initials: J
authors.lastname: Ward
authors.forename: Laurie A
authors.initials: LA
authors.lastname: Waterman
authors.forename: John C
authors.initials: JC
authors.lastname: Baird
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D015331:Cohort Studies; D018450:Disease Progression; D004417:Dyspnea / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology*; D057566:Self Report; D012720:Severity of Illness Index; D013147:Spirometry; D011795:Surveys and Questionnaires