Cord blood vitamin D deficiency is associated with respiratory syncytial virus bronchiolitis

Pediatrics. 2011 Jun;127(6):e1513-20. doi: 10.1542/peds.2010-3054. Epub 2011 May 9.

Abstract

Background: Respiratory syncytial virus (RSV) is the most important pathogen causing severe lower respiratory tract infection (LRTI) in infants. Epidemiologic and basic studies suggest that vitamin D may protect against RSV LRTI.

Objective: To determine the association between plasma vitamin D concentrations at birth and the subsequent risk of RSV LRTI.

Design: A prospective birth cohort study was performed in healthy term neonates. Concentrations of 25-hydroxyvitamin D (25-OHD) in cord blood plasma were related to RSV LRTI in the first year of life, defined as parent-reported LRTI symptoms in a daily log and simultaneous presence of RSV RNA in a nose-throat specimen.

Results: The study population included 156 neonates. Eighteen (12%) developed RSV LRTI. The mean plasma 25-OHD concentration was 82 nmol/L. Overall, 27% of neonates had 25-OHD concentrations < 50 nmol/L, 27% had 50-74 nmol/L and only 46% had 25-OHD 75 nmol/L. Cord blood 25-OHD concentrations were strongly associated with maternal vitamin D3 supplementation during pregnancy. Concentrations of 25-OHD were lower in neonates who subsequently developed RSV LRTI compared with those who did not (65 nmol/L versus 84 nmol/L, P = .009). Neonates born with 25-OHD concentrations <50 nmol/L had a sixfold (95% confidence interval: 1.6-24.9; P = .01) increased risk of RSV LRTI in the first year of life compared with those with 25-OHD concentrations ≥ 75 nmol/L.

Conclusions: Vitamin D deficiency in healthy neonates is associated with increased risk of RSV LRTI in the first year of life. Intensified routine vitamin D supplementation during pregnancy may be a useful strategy to prevent RSV LRTI during infancy.

Publication types

  • Comparative Study
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bronchiolitis / blood*
  • Bronchiolitis / complications
  • Bronchiolitis / virology
  • Female
  • Fetal Blood / metabolism*
  • Humans
  • Infant, Newborn
  • Male
  • Pregnancy
  • Pregnancy Complications, Infectious
  • Prospective Studies
  • RNA, Viral / analysis
  • Respiratory Syncytial Virus Infections / blood*
  • Respiratory Syncytial Virus Infections / complications
  • Respiratory Syncytial Virus Infections / virology
  • Respiratory Syncytial Viruses / genetics
  • Risk Factors
  • Vitamin D / analogs & derivatives*
  • Vitamin D / blood
  • Vitamin D Deficiency / blood*
  • Vitamin D Deficiency / complications

Substances

  • RNA, Viral
  • Vitamin D
  • 25-hydroxyvitamin D