title: Prevalence of 25-hydroxyvitamin D deficiency in child and adolescent patients undergoing hematopoietic cell transplantation compared to a healthy population.
abstract: BACKGROUND
  Pediatric patients undergoing allogeneic hematopoietic cell transplant (HCT) are at risk for low bone mineral density, which may due, in part, to low 25-hydroxyvitamin D levels.
  
  
  METHODS
  We compared the serum 25-hydroxyvitamin D status of 22 pediatric HCT patients with 100 healthy pediatric controls. We determined the prevalence of and risk factors for 25-hydroxyvitamin D insufficiency and deficiency.
  
  
  RESULTS
  Serum 25-hydroxyvitamin D levels were lower in the pediatric HCT patients at time of transplant than healthy pediatric controls (median 19.5 ng/ml vs. 31.0 ng/ml, P < 0.001). Of HCT patients, 27% were 25-hydroxyvitamin D deficient (<15 ng/dl) and 68% insufficient (15-29 ng/dl), compared with 4% and 40%, respectively, of healthy pediatric controls (P < 0.001). In multivariable analysis, treatment with HCT, decreased ambient ultraviolet light exposure, non-Caucasian race, and older age were associated with decreased serum 25-hydroxyvitamin D levels. No association was found between 25-hydroxyvitamin D levels and gender, body mass index, dietary vitamin D intake, or patient-reported vitamin D supplementation. Few patients in either group reported sunscreen use, vitamin D supplementation, or recommended dietary vitamin D intake.
  
  
  CONCLUSIONS
  At time of transplant, pediatric HCT patients frequently have 25-hydroxyvitamin D insufficiency/deficiency, and this occurs more commonly than in the healthy pediatric population. HCT patients rarely follow recommended guidelines to take supplemental vitamin D, consume the Recommended Daily Allowance for vitamin D, or regularly use sunscreen. Further studies are needed to determine whether vitamin D insufficiency/deficiency persists long term in HCT patients and requires dietary and behavioral interventions.
authors.affiliation: Department of Pediatrics, Division of Endocrinology and Diabetes, Vanderbilt University School of Medicine, Nashville, Tennessee.
authors.forename: Jill
authors.initials: J
authors.lastname: Simmons
authors.forename: Craig
authors.initials: C
authors.lastname: Sheedy
authors.forename: Haerin
authors.initials: H
authors.lastname: Lee
authors.forename: Shannon
authors.initials: S
authors.lastname: Koh
authors.forename: Joann
authors.initials: J
authors.lastname: Alvarez
authors.forename: Tatsuki
authors.initials: T
authors.lastname: Koyama
authors.forename: Debra
authors.initials: D
authors.lastname: Friedman
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004032:Diet; D019587:Dietary Supplements; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D008297:Male; D015995:Prevalence; D013472:Sunlight; D011795:Surveys and Questionnaires; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000453:epidemiology*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: hematopoietic stem cell transplantation; pediatric; vitamin D deficiency; vitamin D insufficiency