title: Sex influences on lung function and medication in childhood asthma.
abstract: OBJECTIVE
  To evaluate possible sex differences in prevalence, diagnosis and treatment of asthma, and influence on lung function associated with asthma severity in a population-based birth cohort (BAMSE) of 4089 children.
  
  
  METHODS
  At 4-y follow-up, 92% responded to a questionnaire on symptoms of asthma, current medication and doctor's diagnosis of asthma. A total of 2965 children participated in clinical testing, including measurements of peak expiratory flow (PEF), and were assigned to groups of asthma or no asthma by reported airway symptoms.
  
  
  RESULTS
  Children in asthma groups had lower PEF readings compared to healthy children. This effect was most pronounced for both sexes in the persistent group (boys p<0.05, girls p<0.001) and for girls in the transient group (p<0.01). A doctor's diagnosis of asthma did not significantly differ between boys and girls, but significantly more boys than girls had inhaled corticosteroids, even when stratifying by frequency of symptoms.
  
  
  CONCLUSIONS
  These results suggest that when 4-y-old children are stratified according to common diagnostic criteria, girls have a larger effect on PEF of asthma symptoms and are less frequently treated compared to boys.
authors.affiliation: Division of Occupational Medicine, Department of Public Health Sciences, Karolinska Institute, Stockholm, Sweden. jenny.hallberg@phs.ki.se
authors.forename: Jenny
authors.initials: J
authors.lastname: Hallberg
authors.forename: Martin
authors.initials: M
authors.lastname: Anderson
authors.forename: Magnus
authors.initials: M
authors.lastname: Wickman
authors.forename: Magnus
authors.initials: M
authors.lastname: Svartengren
mesh_terms: D017668:Age of Onset; D001249:Asthma / Q000188:drug therapy / Q000453:epidemiology* / Q000503:physiopathology*; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008168:Lung / Q000503:physiopathology*; D008297:Male; D010366:Peak Expiratory Flow Rate; D010818:Practice Patterns, Physicians'; D012737:Sex Factors