title: Relationship between prenatal and postnatal exposures to folate and risks of allergic and respiratory diseases in early childhood.
abstract: BACKGROUND
  It is uncertain whether folate is risk or preventive factor for allergic and respiratory diseases.
  
  
  OBJECTIVE
  To determine the relationship between maternal or offspring folate status and subsequent development of allergic and respiratory diseases in early childhood.
  
  
  METHODS
  In total, 917 mother-child pairs from a prospective birth cohort in South Korea were studied. Data regarding the children's allergic and respiratory outcomes were obtained from standardized questionnaires completed by the mothers at postnatal months 6, 12, and 24. Serum folate levels were measured in the mothers at mid- and late-pregnancy, and in their children at 24 months of age. Atopic biomarkers were measured in the cord blood (CB) and at 24 months after birth. Biomarkers and clinical outcomes were analyzed and compared between the mother-child pairs divided into two groups according to median serum folate status at mid- and late-pregnancy.
  
  
  RESULTS
  Serum folate levels during mid-pregnancy were inversely associated with CB eosinophil count (adjusted odds ratio [OR] 0.72, 95% confidence interval [CI], 0.54-0.96) and positively associated with CB interleukin-10 levels (1.47, 1.11-1.94). Maternal folate level above the median value (≥9.5 ng/ml) during mid-pregnancy was associated with a decreased risk for the child of lower respiratory tract infections (LRTIs) at 6 months of age (adjusted OR 0.50, 95% CI 0.28-0.91) and atopic dermatitis (AD) at 24 months (adjusted OR 0.52, 95% CI 0.31-0.88), but not with LRTIs and AD at other ages.
  
  
  CONCLUSIONS
  A relatively high maternal serum folate level in mid-pregnancy was associated with a decreased risk of LRTIs and AD in early childhood.
authors.affiliation: Department of Pediatrics, Ulsan University Hospital, University of Ulsan Collage of Medicine, Ulsan, Korea.
authors.forename: Ja Hyeong
authors.initials: JH
authors.lastname: Kim
authors.forename: Kyoung-Sook
authors.initials: KS
authors.lastname: Jeong
authors.forename: Eun-Hee
authors.initials: EH
authors.lastname: Ha
authors.forename: Hyesook
authors.initials: H
authors.lastname: Park
authors.forename: Mina
authors.initials: M
authors.lastname: Ha
authors.forename: Yun-Chul
authors.initials: YC
authors.lastname: Hong
authors.forename: Soo-Young
authors.initials: SY
authors.lastname: Bhang
authors.forename: Soo-Jeong
authors.initials: SJ
authors.lastname: Lee
authors.forename: Kyung-Yeon
authors.initials: KY
authors.lastname: Lee
authors.forename: Seon-Ho
authors.initials: SH
authors.lastname: Lee
authors.forename: Yangho
authors.initials: Y
authors.lastname: Kim
authors.forename: Min-Ho
authors.initials: MH
authors.lastname: Kim
authors.forename: Namsoo
authors.initials: N
authors.lastname: Chang
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D002452:Cell Count; D002675:Child, Preschool; D015331:Cohort Studies; D003876:Dermatitis, Atopic / Q000097:blood / Q000453:epidemiology*; D004804:Eosinophils / Q000378:metabolism; D005260:Female; D005312:Fetal Blood / Q000166:cytology; D005492:Folic Acid / Q000097:blood*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016753:Interleukin-10 / Q000097:blood; D008297:Male; D011247:Pregnancy; D056910:Republic of Korea / Q000453:epidemiology; D012141:Respiratory Tract Infections / Q000097:blood / Q000453:epidemiology*; D012306:Risk
chemical_list: D015415:Biomarkers; D016753:Interleukin-10; D005492:Folic Acid
keywords: allergic disease; cord blood; folate; lower respiratory tract infections; pregnancy