title: Bioavailability of vitamin D in malnourished adolescents with anorexia nervosa.
abstract: BACKGROUND
  Young women with anorexia nervosa (AN) have a normal vitamin D status. The bioavailability of vitamin D during malnutrition is unknown.
  
  
  OBJECTIVE
  The objective of the study was to examine the serum response to oral ergocalciferol in AN.
  
  
  METHODS
  This was a prospective cohort study, conducted in 2007-2009 at a tertiary care center.
  
  
  METHODS
  Twelve adolescents with AN (age 19.6 ± 2.0 yr, body mass index 16.5 ± 1.4 kg/m²) and 12 matched healthy controls (20.0 ± 2.4 yr, 22.7 ± 1.0 kg/m²) received one baseline 50,000 IU oral dose of ergocalciferol.
  
  
  RESULTS
  Serum D₂, D₃, 25-hydroxyvitamin D, and 1,25-dihydroxyvitamin D, collected before ingestion, at 6 and 24 h and weekly for 4 wk, and body composition measures were measured.
  
  
  RESULTS
  The AN group was severely malnourished (77.2 ± 6.3% median body weight), whereas the control group was normal weighted (106.2 ± 6.2%). From a common baseline D₂ (1.5 ± 1.6 nmol/liter, P =0.34) the groups diverged (time × group interaction P = 0.04), peaking at 70 ± 34 nmol/liter at 6 h in controls compared with 43 ± 28 nmol/liter in AN subjects (P = 0.008). The D₂ trajectories converged at 24 h (57 nmol/liter, P = 0.98) and returned to near baseline at 1 wk. Baseline D₃ was higher in AN subjects (12.1 ± 9.6 vs. 3.1 ± 2.3 nmol/liter, P < 0.001) and remained higher throughout. 25-Hydroxyvitamin D followed a common trajectory (time × group interaction P = 0.15), rising to 45 ± 10 nmol/liter at 24 h but returning to baseline by wk 3 (P = 0.36). Correlating vitamin D levels with fat measures (body mass index, body fat) produced similar findings.
  
  
  CONCLUSIONS
  Despite severe malnutrition, young women with AN had a similar bioavailability of oral ergocalciferol as the healthy-weighted controls. Vitamin D dosing for patients suffering from malnutrition may not differ from that for normal-weighted adolescents.
authors.affiliation: Division of Adolescent Medicine, Children's Hospital Boston, Boston, Massachusetts 02115, USA. amy.divasta@childrens.harvard.edu
authors.forename: Amy D
authors.initials: AD
authors.lastname: Divasta
authors.forename: Henry A
authors.initials: HA
authors.lastname: Feldman
authors.forename: Julia N
authors.initials: JN
authors.lastname: Brown
authors.forename: Courtney
authors.initials: C
authors.lastname: Giancaterino
authors.forename: Michael F
authors.initials: MF
authors.lastname: Holick
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Gordon
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000856:Anorexia Nervosa / Q000188:drug therapy* / Q000378:metabolism*; D002112:Calcifediol / Q000097:blood; D002762:Cholecalciferol / Q000097:blood; D015331:Cohort Studies; D004872:Ergocalciferols / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D005260:Female; D006801:Humans; D044342:Malnutrition / Q000188:drug therapy* / Q000378:metabolism*; D010281:Parathyroid Hormone / Q000097:blood; D011446:Prospective Studies; D014815:Vitamins / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics; D055815:Young Adult
chemical_list: D004872:Ergocalciferols; D010281:Parathyroid Hormone; D014815:Vitamins; D002762:Cholecalciferol; D002112:Calcifediol