title: A longitudinal study of lung function from 1 month to 18 years of age.
abstract: BACKGROUND
  Our hypothesis was that factors associated with wheeze will be associated with changes in lung function trajectory between 1 month and 18 years of age.
  
  
  METHODS
  Measurements of lung function were made in individuals aged 1, 6 and 12 months (V'maxFRC), and also at ages 6, 12 and 18 years (FEF(25-75)). Changes in lung function over time relative to sex, a history of asthma, maternal asthma and other factors were explored using random coefficient models.
  
  
  RESULTS
  Lung function (maximal flow at functional residual capacity in infants and FEF(25-75) in children) was determined in 241 individuals at 1 month, 192 at 6 months, 164 at 12 months, 106 at 6 years, 183 at 12 years and 141 at 18 years. In the multivariable model, maternal asthma (mean reduction in lung function 9.8%), flow limitation (mean reduction 17.4%), infant atopy (mean reduction 12.6%) and maternal smoking (mean reduction in lung function 8.1%) were acting independently. When interactions with time were sought, the reduction in lung function associated with maternal asthma and infant atopy were consistent over time, but % lung function increased in boys by a mean of 1%/year compared with girls, in flow-limited individuals by 3.0%/year and by 0.9%/year for those exposed to maternal smoking during pregnancy compared to other cohort members.
  
  
  CONCLUSIONS
  Decrements in lung function in 18-year-olds associated with maternal asthma and early onset atopy may be determined by 1 month of age. Low initial lung function in some individuals can 'recover' in some settings.
authors.affiliation: Department of Child Health, University of Aberdeen, Aberdeen, UK.
authors.forename: Steve
authors.initials: S
authors.lastname: Turner
authors.affiliation: Medical Statistics Team, University of Aberdeen, Aberdeen, UK.
authors.forename: Shona
authors.initials: S
authors.lastname: Fielding
authors.affiliation: School of Child Health, University of Western Australia, Perth, Australia.
authors.forename: Dave
authors.initials: D
authors.lastname: Mullane
authors.affiliation: School of Child Health, University of Western Australia, Perth, Australia.
authors.forename: Des W
authors.initials: DW
authors.lastname: Cox
authors.affiliation: School of Child Health, University of Western Australia, Perth, Australia.
authors.forename: Jack
authors.initials: J
authors.lastname: Goldblatt
authors.affiliation: School of Child Health, University of Western Australia, Perth, Australia.
authors.forename: Lou
authors.initials: L
authors.lastname: Landau
authors.affiliation: School of Child Health, University of Western Australia, Perth, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: le Souef
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000150:complications / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005544:Forecasting; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008168:Lung / Q000503:physiopathology*; D008297:Male; D018811:Maternal Exposure / Q000009:adverse effects*; D011247:Pregnancy; D012129:Respiratory Function Tests; D012143:Respiratory Physiological Phenomena; D012135:Respiratory Sounds / Q000209:etiology / Q000503:physiopathology*
keywords: Asthma Mechanisms; Paediatric asthma