title: Breast-feeding in relation to asthma, lung function, and sensitization in young schoolchildren.
abstract: BACKGROUND
  The evidence from previous studies on beneficial effects of breast-feeding in relation to development of asthma is conflicting.
  
  
  OBJECTIVE
  To investigate the relation between breast-feeding and asthma and/or sensitization during the first 8 years of life.
  
  
  METHODS
  In a birth cohort, children were followed up to 8 years by questionnaires at ages 2 months and 1, 2, 4, and 8 years to collect information on exposures and health effects. Determination of serum IgE antibodies to common inhalant and food allergens was performed at 4 and 8 years. Longitudinal analyses were applied by using general estimated equations. The study population consisted of 3825 children (93% of the original cohort), of whom 2370 gave blood and 2564 performed lung function measurements at 8 years.
  
  
  RESULTS
  Children exclusively breast-fed 4 months or more had a reduced risk of asthma during the first 8 years of life (adjusted odds ratio [OR], 0.63; 95% CI, 0.50-0.78) compared with children breast-fed less than 4 months. At 8 years, reduced risks of sensitization (adjusted OR, 0.79; 95% CI, 0.64-0.99) and asthma in combination with sensitization (adjusted OR, 0.59; 95% CI, 0.37-0.93) were seen among children exclusively breast-fed 4 months or more. This group also had a significantly better lung function measured with peak expiratory flow.
  
  
  CONCLUSIONS
  Breast-feeding for 4 months or more seems to reduce the risk of asthma up to 8 years. At this age, a reduced risk was observed particularly for asthma combined with sensitization. Furthermore, breast-feeding seems to have a beneficial effect on lung function.
authors.affiliation: Institute of Environmental Medicine, Karolinska Institutet, SE-171 76 Stockholm, Sweden. inger.kull@ki.se
authors.forename: Inger
authors.initials: I
authors.lastname: Kull
authors.forename: Erik
authors.initials: E
authors.lastname: Melen
authors.forename: Johan
authors.initials: J
authors.lastname: Alm
authors.forename: Jenny
authors.initials: J
authors.lastname: Hallberg
authors.forename: Magnus
authors.initials: M
authors.lastname: Svartengren
authors.forename: Marianne
authors.initials: M
authors.lastname: van Hage
authors.forename: Göran
authors.initials: G
authors.lastname: Pershagen
authors.forename: Magnus
authors.initials: M
authors.lastname: Wickman
authors.forename: Anna
authors.initials: A
authors.lastname: Bergström
mesh_terms: D000485:Allergens / Q000009:adverse effects / Q000276:immunology; D001249:Asthma / Q000453:epidemiology / Q000517:prevention & control*; D001942:Breast Feeding; D002648:Child; D002675:Child, Preschool; D005260:Female; D005512:Food Hypersensitivity / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D006967:Hypersensitivity / Q000453:epidemiology* / Q000209:etiology; D007073:Immunoglobulin E / Q000097:blood; D015994:Incidence; D007223:Infant; D019570:Inhalation Exposure; D008297:Male; D012129:Respiratory Function Tests; D011795:Surveys and Questionnaires
chemical_list: D000485:Allergens; D007073:Immunoglobulin E