title: Risk factors for hospital admission for asthma from childhood to young adulthood: a longitudinal population study.
abstract: BACKGROUND
  Predictors of hospital admissions for asthma in children and young adults in a general population are not well defined, because most studies have used selected subpopulations.
  
  
  OBJECTIVE
  The purpose of this investigation was to determine risk factors for single and multiple hospital admissions for asthma.
  
  
  METHODS
  The members of a population-based, unselected birth cohort of 1037 New Zealanders answered questionnaires and underwent lung function, airway responsiveness, and allergy testing on 7 occasions to the age of 26 years.
  
  
  RESULTS
  Among the 766 study members (74% of the cohort) who reported wheezing symptoms ever by the age of 26 years, 136 hospitalizations were reported by 62 individuals (8.3% of those at risk, 6.2% of the total cohort). Only 55 of these 136 admissions involved children less than 9 years of age; admissions continued to occur between the ages of 9 and 18 years (40 admissions) and at >18 years (41 admissions). Those admitted were predominantly male, had earlier ages of onset of symptoms, were more atopic, and had more airway hyperresponsiveness to methacholine than those not admitted. Frequent symptoms and low lung function were evident among the 45 study members with single admissions and even more evident among the 17 study members with multiple (2-10) admissions.
  
  
  CONCLUSIONS
  A surprisingly large fraction of this unselected population experienced hospitalization for asthma during the 26-year follow-up, many being admitted in later childhood, adolescence, and early adulthood. Clinical characteristics and markers of severity, including frequent respiratory symptoms, airway hyperresponsiveness, atopy, and low lung function, identify those at high risk for hospitalization for asthma, particularly with respect to multiple admissions.
authors.affiliation: Firestone Institute for Respiratory Health, St Joseph's Healthcare, and McMaster University, 50 Charlton Avenue East, Hamilton, Ontario L8N 4A6, Canada.
authors.forename: Finn
authors.initials: F
authors.lastname: Rasmussen
authors.forename: D Robin
authors.initials: DR
authors.lastname: Taylor
authors.forename: Erin M
authors.initials: EM
authors.lastname: Flannery
authors.forename: Jan O
authors.initials: JO
authors.lastname: Cowan
authors.forename: Justina M
authors.initials: JM
authors.lastname: Greene
authors.forename: G Peter
authors.initials: GP
authors.lastname: Herbison
authors.forename: Malcolm R
authors.initials: MR
authors.lastname: Sears
mesh_terms: D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000188:drug therapy / Q000453:epidemiology* / Q000276:immunology / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009520:New Zealand / Q000453:epidemiology; D010343:Patient Admission / Q000706:statistics & numerical data*; D010359:Patient Readmission / Q000706:statistics & numerical data; D011159:Population Surveillance; D012129:Respiratory Function Tests; D012307:Risk Factors; D011795:Surveys and Questionnaires