title: Changes in forced expiratory volume in 1 second over time in COPD.
abstract: BACKGROUND
  A key feature of chronic obstructive pulmonary disease (COPD) is an accelerated rate of decline in forced expiratory volume in 1 second (FEV(1)), but data on the variability and determinants of this change in patients who have established disease are scarce.
  
  
  METHODS
  We analyzed the changes in FEV(1) after administration of a bronchodilator over a 3-year period in 2163 patients. A random-coefficient model was used to evaluate possible predictors of both FEV(1) levels and their changes over time.
  
  
  RESULTS
  The mean (±SE) rate of change in FEV(1) was a decline of 33±2 ml per year, with significant variation among the patients studied. The between-patient standard deviation for the rate of decline was 59 ml per year. Over the 3-year study period, 38% of patients had an estimated decline in FEV(1) of more than 40 ml per year, 31% had a decline of 21 to 40 ml per year, 23% had a change in FEV(1) that ranged from a decrease of 20 ml per year to an increase of 20 ml per year, and 8% had an increase of more than 20 ml per year. The mean rate of decline in FEV(1) was 21±4 ml per year greater in current smokers than in current nonsmokers, 13±4 ml per year greater in patients with emphysema than in those without emphysema, and 17±4 ml per year greater in patients with bronchodilator reversibility than in those without reversibility.
  
  
  CONCLUSIONS
  The rate of change in FEV(1) among patients with COPD is highly variable, with increased rates of decline among current smokers, patients with bronchodilator reversibility, and patients with emphysema.
authors: Respiratory Section, Hvidovre Hospital, Hvidovre, Denmark. jvestbo@dadlnet.dk
authors: Jørgen
authors: J
authors: Vestbo
authors: Lisa D
authors: LD
authors: Edwards
authors: Paul D
authors: PD
authors: Scanlon
authors: Julie C
authors: JC
authors: Yates
authors: Alvar
authors: A
authors: Agusti
authors: Per
authors: P
authors: Bakke
authors: Peter M A
authors: PM
authors: Calverley
authors: Bartolome
authors: B
authors: Celli
authors: Harvey O
authors: HO
authors: Coxson
authors: Courtney
authors: C
authors: Crim
authors: David A
authors: DA
authors: Lomas
authors: William
authors: W
authors: MacNee
authors: Bruce E
authors: BE
authors: Miller
authors: Edwin K
authors: EK
authors: Silverman
authors: Ruth
authors: R
authors: Tal-Singer
authors: Emiel
authors: E
authors: Wouters
authors: Stephen I
authors: SI
authors: Rennard
mesh_terms: D000368:Aged; D001499:Bayes Theorem; D015415:Biomarkers / Q000097:blood*; D002097:C-Reactive Protein / Q000032:analysis; D016207:Cytokines / Q000097:blood; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D019370:Observation; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood / Q000503:physiopathology*; D014598:Uteroglobin / Q000097:blood
chemical_list: D015415:Biomarkers; D016207:Cytokines; C556389:SCGB1A1 protein, human; D002097:C-Reactive Protein; D014598:Uteroglobin