title: Prevalence of asthma and bronchial hyperreactivity in Danish schoolchildren: no change over 10 years.
abstract: OBJECTIVE
  To describe the point prevalence of current physician-diagnosed asthma and bronchial hyperreactivity (BHR) in 2001 among unselected Danish schoolchildren aged 6-17 years, compared with the prevalence from a similar study from 1990 to 1991.
  
  
  METHODS
  Cross-sectional study using parental questionnaire on asthma and respiratory symptoms combined with a 6-min free running test with peak expiratory flow rate (PEFR) measurement (n = 1051, response rate 89.3%). Results were compared with those of a similar study in the same area from 1990 to 1991. Main outcome measures were current physician-diagnosed asthma or BHR in children without physician-diagnosed asthma measured by either a decrease in lung function after standardized running test and/or variability in PEFR on home monitoring.
  
  
  RESULTS
  The prevalence of current physician-diagnosed asthma was 4.0% [95% confidence interval (CI) 2.7-5.3%] in 1990-1991 and 3.6% (95% CI 2.4-4.8%) in 2001. The prevalence of BHR was 3.2% (95% CI 2.0-4.4%) in 1990-1991 and 2.0% (95% CI 1.1-2.9%) in 2001. The combined prevalence was 7.2% (95% CI 5.4-8.9%) in 1990-1991 and 5.6% (95% CI 4.2-7.1%) in 2001.
  
  
  CONCLUSIONS
  The point prevalence of current physician-diagnosed asthma and BHR among unselected Danish schoolchildren aged 6-17 years was unchanged over 10 years between 1990-1991 and 2001.
authors.affiliation: Department of Pediatrics, Herlev Hospital, University of Copenhagen, Herlev, Denmark. monica@zilmer.dk
authors.forename: M
authors.initials: M
authors.lastname: Zilmer
authors.forename: N P
authors.initials: NP
authors.lastname: Steen
authors.forename: G
authors.initials: G
authors.lastname: Zachariassen
authors.forename: T
authors.initials: T
authors.lastname: Duus
authors.forename: B
authors.initials: B
authors.lastname: Kristiansen
authors.forename: S
authors.initials: S
authors.lastname: Halken
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D002648:Child; D003430:Cross-Sectional Studies; D003718:Denmark / Q000453:epidemiology; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D010366:Peak Expiratory Flow Rate / Q000502:physiology; D015995:Prevalence; D011795:Surveys and Questionnaires