title: Early childhood wheezing is associated with lower lung function in cystic fibrosis.
abstract: OBJECTIVE
  To study the association between wheezing in children with cystic fibrosis (CF) and lung function in later life.
  
  
  METHODS
  We used data from the Epidemiologic Study of CF, a longitudinal observational study from 1994 to 2005. Wheezing phenotypes were defined as: no wheezing in the first 6 years of life (NW), transient wheezing (TW; wheezing <3 years old, but no wheezing after 3), late wheezing (LW; wheezing only after age 3 years), and persistent wheezing (PW; wheezing both before and after age 3 years). A linear regression model was developed predicting the best forced expiratory volume in 1 sec (FEV1 ) at age 6 or 7 years (6 to <8) for each wheezing phenotype.
  
  
  RESULTS
  A total of 1302 children met the cohort inclusion criteria; 61% of the cohort had wheezing in the first 6 years of life. A history of any wheezing in the first 6 years of life was associated with a significantly lower FEV1 at 6 to <8 years compared to children with NW. The FEV1 of children with NW at age 6 to <8 years was 104% predicted, whereas the mean FEV1 in TW, LW, and PW groups was 98%, 100%, and 96% predicted, respectively (P < 0.05 compared to NW).
  
  
  CONCLUSIONS
  Childhood wheezing in CF is common and is associated with lower lung function at age 6 to <8 years. Our results identify a clinical feature in early childhood CF associated with lower lung function in later life.
authors.affiliation: Department of Pediatrics, University of Rochester, Rochester, New York.
authors.forename: Clement L
authors.initials: CL
authors.lastname: Ren
authors.forename: Michael W
authors.initials: MW
authors.lastname: Konstan
authors.forename: Margaret
authors.initials: M
authors.lastname: Rosenfeld
authors.forename: David J
authors.initials: DJ
authors.lastname: Pasta
authors.forename: Stefanie J
authors.initials: SJ
authors.lastname: Millar
authors.forename: Wayne J
authors.initials: WJ
authors.lastname: Morgan
mesh_terms: D017668:Age of Onset; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003550:Cystic Fibrosis / Q000453:epidemiology / Q000503:physiopathology*; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D008168:Lung / Q000503:physiopathology*; D008297:Male; D011379:Prognosis; D011446:Prospective Studies; D012135:Respiratory Sounds / Q000503:physiopathology*; D013147:Spirometry; D014797:Vital Capacity
keywords: cystic fibrosis; epidemiology; infants; spirometry; wheeze