title: The association of vitamin D status with pediatric critical illness.
abstract: OBJECTIVE
  Vitamin D is a pleiotropic hormone important for the proper functioning of multiple organ systems. It has been hypothesized that vitamin D deficiency could contribute to or worsen outcomes in critical illness. The study objective was to determine the prevalence of vitamin D deficiency, risk factors for its presence, and potential association with clinically relevant outcomes in critically ill children.
  
  
  METHODS
  A prospective cohort study, conducted from 2005 to 2008 in 6 tertiary-care PICUs in Canada. Data and biological samples from 326 critically ill children up to 17 years of age were available for analysis. Total serum 25 hydroxyvitamin D or 25(OH)D was measured by using liquid chromatography-mass spectrometry.
  
  
  RESULTS
  The prevalence of 25(OH)D <50 nmol/L was 69% (95% confidence interval, 64-74), and 23% (95% confidence interval, 19-28) for 25(OH)D between 50 to 75 nmol/L. Lower levels were associated with hypocalcemia, catecholamine utilization, and significant fluid bolus administration. Vitamin D deficiency was independently associated with a longer PICU length of stay (+1.92 days, P = .03) and increasing severity of illness as determined by the Pediatric Risk of Mortality score with every additional point increasing the likelihood of being vitamin D deficient by 8% (P = .005).
  
  
  CONCLUSIONS
  This study provides evidence that vitamin D deficiency is both common among critically ill children and associated with greater severity of critical illness. Further research will determine whether targeted vitamin D supplementation or rapid restoration will improve outcome.
authors.affiliation: Division of Critical Care, Department of Pediatrics, Faculty of Medicine, University of Ottawa, Children’s Hospital of Eastern Ontario, Canada. dmcnally@cheo.on.ca
authors.forename: J Dayre
authors.initials: JD
authors.lastname: McNally
authors.forename: Kusum
authors.initials: K
authors.lastname: Menon
authors.forename: Pranesh
authors.initials: P
authors.lastname: Chakraborty
authors.forename: Lawrence
authors.initials: L
authors.lastname: Fisher
authors.forename: Kathryn A
authors.initials: KA
authors.lastname: Williams
authors.forename: Osama Y
authors.initials: OY
authors.lastname: Al-Dirbashi
authors.forename: Dermot R
authors.initials: DR
authors.lastname: Doherty
mesh_terms: D000293:Adolescent; D002112:Calcifediol / Q000097:blood; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D016638:Critical Illness; D005260:Female; D006801:Humans; D007223:Infant; D015278:Intensive Care Units, Pediatric; D007902:Length of Stay; D008297:Male; D012307:Risk Factors; D012720:Severity of Illness Index; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications*
chemical_list: D002112:Calcifediol