title: Lack of relationship between birth conditions and allergic disorders in Japanese children aged 3 years.
abstract: BACKGROUND
  The current cross-sectional study examined the associations between low birth weight (LBW), preterm birth, and small-for-gestational-age (SGA) and the prevalence of wheeze, asthma, and eczema in Japanese children aged 3 years.
  
  
  METHODS
  Study subjects were 2004 children. All data were obtained using a questionnaire. Outcomes were defined according to the criteria of the International Study of Asthma and Allergies in Childhood. Adjustment was made for sex, number of siblings, breastfeeding duration, paternal and maternal educational level, paternal and maternal history of allergic disorders, maternal smoking during pregnancy, secondhand smoke exposure at home, and gestational age at birth.
  
  
  RESULTS
  The prevalence of wheeze, asthma, and eczema in the previous 12 months were 22.1%, 9.0%, and 17.5%, respectively, and 8.4% were classified as LBW (<2500 g), 4.7% as preterm birth (<37 weeks), and 7.1% as SGA (<10th percentile). There were no significant associations between LBW, preterm birth, or SGA and the prevalence of wheeze, asthma, or eczema. A positive relationship between preterm birth and asthma was of borderline significance in children whose mothers had smoked during pregnancy (adjusted OR: 4.71 [95% CI: 0.97-21.39]), but not in those whose mothers had never smoked during pregnancy; the multiplicative interaction between preterm birth and maternal smoking during pregnancy with respect to asthma was significant (p = .04).
  
  
  CONCLUSIONS
  The current study failed to detect significant associations between birth conditions and allergic disorders. Nevertheless, we did find evidence for an interaction between preterm birth and maternal smoking during pregnancy affecting asthma.
authors.affiliation: Department of Preventive Medicine and Public Health, Faculty of Medicine, Fukuoka University, Fukuoka, Japan. miyake-y@fukuoka-u.ac.jp
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Miyake
authors.forename: Keiko
authors.initials: K
authors.lastname: Tanaka
mesh_terms: D044466:Asian People; D001249:Asthma / Q000453:epidemiology*; D001724:Birth Weight; D001942:Breast Feeding; D002675:Child, Preschool; D004485:Eczema / Q000453:epidemiology*; D004781:Environmental Exposure; D005220:Fathers; D005260:Female; D005865:Gestational Age; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008431:Maternal-Fetal Exchange; D009035:Mothers; D016017:Odds Ratio; D011247:Pregnancy; D015995:Prevalence; D012135:Respiratory Sounds; D012907:Smoking / Q000453:epidemiology; D011795:Surveys and Questionnaires; D014028:Tobacco Smoke Pollution
chemical_list: D014028:Tobacco Smoke Pollution