title: Vitamin D status in anorexia nervosa: A meta-analysis.
abstract: OBJECTIVE
  In anorexia nervosa (AN), osteoporosis and osteopenia are common, which have been associated with low circulating levels of vitamin D (VitD) in other settings. We aimed to meta-analyze cross-sectional studies reporting on VitD parameters in patients with AN and healthy controls (HCs).
  
  
  METHODS
  Electronic PubMed search from database inception until December 31, 2013 and meta-analysis of cross-sectional studies comparing serum levels of 25-hydroxyvitamin D (25OH-D), 1,25-dihydroxyvitamin D (1,25OH-D) and dietary VitD between patients with AN and HCs, before or after VitD supplementation. We calculated random effects standardized mean differences (SMDs) ±95% confidence intervals (CIs) as effect size measures.
  
  
  RESULTS
  Out of 1,739 initial hits, 15 studies with a total of 927 participants (AN = 408 and HCs = 519) were meta-analyzed. In the unsupplemented state, both serum 25OH-D (studies = 4; n = 168; SMD = -0.43; 95%CI: -0.83 to -0.03; p = .03) and 1,25OH-D levels (studies = 4; n = 113; SMD = -1.06; 95%CI: -1.47 to -0.66; p < .00001) were significantly lower in AN than HCs. In AN patients treated with cholecalciferol supplementation, serum 25OH-D levels were significantly higher than in HCs (studies = 5; n = 449; SMD = 0.66; 95%CI: 0.01-1.31; p = .05). Paradoxically, despite lower 25OH-D and 1,25OH-D levels, AN patients reported similar intake of VitD compared to HCs (studies = 6; n = 314; SMD = 0.33; 95%CI: -0.16, 0.81; p = .19).
  
  
  CONCLUSIONS
  Although AN patients reported similar dietary VitD intake compared to HCs, AN patients had significantly lower 25OH-D and 1,25OH-D levels without supplementation. Conversely, supplementation with cholecalciferol fully normalized VitD serum levels. Future studies are needed to clarify the role of VitD supplementation in AN for improving bone health.
authors.affiliation: Department of Medicine, DIMED, Geriatrics Section, University of Padova, Padova, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Veronese
authors.affiliation: Department of Neurosciences, University of Padova, Padova, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Solmi
authors.affiliation: Department of Food and Human Nutrition Science, University Campus Bio-Medico, Rome, Italy.
authors.forename: Wanda
authors.initials: W
authors.lastname: Rizza
authors.affiliation: Department of Medicine, DIMED, Geriatrics Section, University of Padova, Padova, Italy.
authors.forename: Enzo
authors.initials: E
authors.lastname: Manzato
authors.affiliation: Department of Medicine, DIMED, Geriatrics Section, University of Padova, Padova, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Sergi
authors.affiliation: Department of Neurosciences, University of Padova, Padova, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Santonastaso
authors.affiliation: Department of Medicine, DIMED, University of Padova, Padova, Italy.
authors.forename: Lorenza
authors.initials: L
authors.lastname: Caregaro
authors.affiliation: Department of Neurosciences, University of Padova, Padova, Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Favaro
authors.affiliation: The Zucker Hillside Hospital, Department of Psychiatry, North Shore - Long Island Jewish Health System, Glen Oaks, New York, USA.|Hofstra North Shore LIJ School of Medicine, Department of Psychiatry and Molecular Medicine, Hempstead, New York, USA.|The Feinstein Institute for Medical Research, Psychiatric Neuroscience Center of Excellence, Manhasset, New York, USA.|Albert Einstein College of Medicine, Department of Psychiatry and Behavioral Sciences, Bronx, New York, USA.
authors.forename: Christoph U
authors.initials: CU
authors.lastname: Correll
mesh_terms: D000328:Adult; D000856:Anorexia Nervosa / Q000097:blood*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000378:metabolism; D055815:Young Adult
chemical_list: D014807:Vitamin D; C097949:1,25-dihydroxyvitamin D
keywords: 25 hydroxyvitamin D; anorexia nervosa; eating disorders; vitamin D