title: Low cord-serum 25-hydroxyvitamin D levels are associated with poor lung function performance and increased respiratory infection in infancy.
abstract: BACKGROUND
  Perinatal vitamin D deficiency is associated with a higher risk of wheezing in childhood. However, the relationship between vitamin D levels and lung function in infancy has not been investigated. The aim of this study was to investigate the impact of perinatal vitamin D levels on respiratory function and disease outcome in infancy.
  
  
  METHODS
  Full-term infants without any chronic diseases or major anomalies were enrolled in the Prediction of Allergies in Taiwanese Children cohort study. Maternal and cord blood were collected for determining the 25(OH)D level. Questionnaires were recorded at birth and 6 months of age. Infant lung function, including tidal breathing analysis, respiratory mechanics, and forced tidal expiration, was tested at 6 months of age.
  
  
  RESULTS
  A total of 122 mother-infant pairs were enrolled in this study, and 71 infants underwent lung function testing at 6 months of age. 25(OH)D levels in maternal and cord serum were highly correlated (r2 = 0.457, p < 0.0001). Infants with lower cord serum 25(OH)D levels (< 13.7 ng/ml) had higher resistance of respiratory system (p < 0.01) and a higher risk of a respiratory tract infection before the age of 6 months (p < 0.01).
  
  
  CONCLUSIONS
  Although a high correlation was found between maternal and cord vitamin D levels, the effect on respiratory outcome was different. Our study is the first to show that low cord 25(OH)D levels significantly relationship with poorer lung function performance and higher likelihood of a respiratory tract infection before 6 months of age.
authors.affiliation: Department of Pediatrics, Chang Gung Memorial Hospital, Linkou Branch, Taoyuan, Taiwan.|Department of Pediatrics, Chang Gung University, Taoyuan, Taiwan.|Prediction of Allergies in Taiwanese Children (PATCH) Cohort Study Group, Keelung, Taiwan.
authors.forename: Shen-Hao
authors.initials: SH
authors.lastname: Lai
authors.affiliation: Department of Pediatrics, Chang Gung University, Taoyuan, Taiwan.|Prediction of Allergies in Taiwanese Children (PATCH) Cohort Study Group, Keelung, Taiwan.|Department of Pediatrics, Chang Gung Memorial Hospital, Keelung Branch, Keelung, Taiwan.
authors.forename: Sui-Ling
authors.initials: SL
authors.lastname: Liao
authors.affiliation: Department of Pediatrics, Chang Gung University, Taoyuan, Taiwan.|Prediction of Allergies in Taiwanese Children (PATCH) Cohort Study Group, Keelung, Taiwan.|Department of Pediatrics, Chang Gung Memorial Hospital, Keelung Branch, Keelung, Taiwan.
authors.forename: Ming-Han
authors.initials: MH
authors.lastname: Tsai
authors.affiliation: Department of Pediatrics, Chang Gung University, Taoyuan, Taiwan.|Prediction of Allergies in Taiwanese Children (PATCH) Cohort Study Group, Keelung, Taiwan.|Department of Pediatrics, Chang Gung Memorial Hospital, Keelung Branch, Keelung, Taiwan.
authors.forename: Man-Chin
authors.initials: MC
authors.lastname: Hua
authors.affiliation: Department of Pediatrics, Chang Gung University, Taoyuan, Taiwan.|Prediction of Allergies in Taiwanese Children (PATCH) Cohort Study Group, Keelung, Taiwan.|Department of Pediatrics, Chang Gung Memorial Hospital, Keelung Branch, Keelung, Taiwan.
authors.forename: Chih-Yung
authors.initials: CY
authors.lastname: Chiu
authors.affiliation: Department of Pediatrics, Chang Gung Memorial Hospital, Linkou Branch, Taoyuan, Taiwan.|Department of Pediatrics, Chang Gung University, Taoyuan, Taiwan.|Prediction of Allergies in Taiwanese Children (PATCH) Cohort Study Group, Keelung, Taiwan.
authors.forename: Kuo-Wei
authors.initials: KW
authors.lastname: Yeh
authors.affiliation: Department of Pediatrics, Chang Gung Memorial Hospital, Linkou Branch, Taoyuan, Taiwan.|Department of Pediatrics, Chang Gung University, Taoyuan, Taiwan.|Prediction of Allergies in Taiwanese Children (PATCH) Cohort Study Group, Keelung, Taiwan.
authors.forename: Tsung-Chieh
authors.initials: TC
authors.lastname: Yao
authors.affiliation: Department of Pediatrics, Chang Gung Memorial Hospital, Linkou Branch, Taoyuan, Taiwan.|Department of Pediatrics, Chang Gung University, Taoyuan, Taiwan.|Prediction of Allergies in Taiwanese Children (PATCH) Cohort Study Group, Keelung, Taiwan.
authors.forename: Jing-Long
authors.initials: JL
authors.lastname: Huang
mesh_terms: D015415:Biomarkers; D005260:Female; D005312:Fetal Blood; D006801:Humans; D007223:Infant; D008168:Lung / Q000503:physiopathology*; D008297:Male; D012129:Respiratory Function Tests; D012141:Respiratory Tract Infections / Q000097:blood* / Q000209:etiology / Q000503:physiopathology*; D012307:Risk Factors; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D015415:Biomarkers; D014807:Vitamin D; C104450:25-hydroxyvitamin D