title: Vitamin D levels and their associations with survival and major disease outcomes in a large cohort of patients with chronic graft-vs-host disease.
abstract: OBJECTIVE
  To identify the factors associated with vitamin D status in patients with chronic graft-vs-host disease (cGVHD) and evaluate the association between serum vitamin D (25(OH)D) levels and cGVHD characteristics and clinical outcomes defined by the National Institutes of Health (NIH) criteria.
  
  
  METHODS
  310 cGVHD patients enrolled in the NIH cGVHD natural history study (clinicaltrials.gov: NCT00092235) were analyzed. Univariate analysis and multiple logistic regression were used to determine the associations between various parameters and 25(OH)D levels, dichotomized into categorical variables: ≤20 and >20 ng/mL, and as a continuous parameter. Multiple logistic regression was used to develop a predictive model for low vitamin D. Survival analysis and association between cGVHD outcomes and 25(OH)D as a continuous as well as categorical variable: ≤20 and >20 ng/mL; <50 and ≥50 ng/mL, and among three ordered categories: ≤20, 20-50, and ≥50 ng/mL, was performed.
  
  
  RESULTS
  69 patients (22.3%) had serum 25(OH)D ≤20 ng/mL. Univariate analysis showed that supplement intake, nutritional status (severely malnourished, moderately malnourished, well-nourished), race (African-American, other), and estimated creatinine clearance (eCCr) were associated with 25(OH)D levels. A predictive model was developed based on supplement intake, nutritional status, race, and eCCr, accurately predicting 77.9% of patients with 25(OH)D ≤20 and 65.2% of those with 25(OH)D >20 ng/mL. No association was found between vitamin D and major cGVHD characteristics, but patients with 25(OH)D ≤20 ng/mL had somewhat decreased survival.
  
  
  CONCLUSIONS
  Nutritional status and adequate supplementation are important to maintain 25(OH)D >20 ng/mL in cGVHD patients. Intervention studies and more research is needed to reveal the underlying mechanism of vitamin D metabolism in cGVHD setting.
authors.affiliation: Mašenjka Katić, Trg 101. brigade HV 2, Zagreb, Croatia, mashakatic@gmail.com.
authors.forename: Mašenjka
authors.initials: M
authors.lastname: Katić
authors.forename: Filip
authors.initials: F
authors.lastname: Pirsl
authors.forename: Seth M
authors.initials: SM
authors.lastname: Steinberg
authors.forename: Marnie
authors.initials: M
authors.lastname: Dobbin
authors.forename: Lauren M
authors.initials: LM
authors.lastname: Curtis
authors.forename: Dražen
authors.initials: D
authors.lastname: Pulanić
authors.forename: Lana
authors.initials: L
authors.lastname: Desnica
authors.forename: Irina
authors.initials: I
authors.lastname: Titarenko
authors.forename: Steven Z
authors.initials: SZ
authors.lastname: Pavletic
mesh_terms: D000328:Adult; D002648:Child; D015331:Cohort Studies; D017523:Croatia; D003430:Cross-Sectional Studies; D005260:Female; D006086:Graft vs Host Disease / Q000097:blood / Q000150:complications / Q000401:mortality* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D011237:Predictive Value of Tests; D011379:Prognosis; D012720:Severity of Illness Index; D016019:Survival Analysis; D014807:Vitamin D / Q000097:blood*; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications* / Q000473:pathology
chemical_list: D014807:Vitamin D