title: Dysregulated mineral metabolism in patients with acute kidney injury and risk of adverse outcomes.
abstract: OBJECTIVE
  Numerous studies have evaluated the prevalence and importance of vitamin D deficiency among patients with chronic kidney disease and end-stage renal disease; however, little is known about vitamin D levels in acute kidney injury (AKI). We evaluated the association between vitamin D metabolites and clinical outcomes among patients with AKI.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  A total of 30 participants with AKI and 30 controls from general hospital wards and intensive care units at a tertiary care hospital were recruited for the study.
  
  
  METHODS
  Plasma levels of 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)2 D], 24R,25-dihydroxyvitamin D3 , vitamin D binding protein (VDBP) and fibroblast growth factor 23 (FGF23) were measured within 24 hours of AKI onset and 5 days later. Bioavailable 25(OH)D and 1,25(OH)2 D levels, defined as the sum of free- and albumin-bound 25(OH)D and 1,25(OH)2 D, were estimated using equations.
  
  
  RESULTS
  Compared to controls, participants with AKI had lower levels of 1,25(OH)2 D [17 (10-22) vs 25 (15-35) pg/ml, P = 0·01], lower levels of VDBP [23 (15-31) vs 29 (25-36) mg/dl, P = 0·003] and similar levels of bioavailable 25(OH)D and 1,25(OH)2 D at enrolment. Levels of bioavailable 25(OH)D were inversely associated with severity of sepsis in the overall sample (P < 0·001). Among participants with AKI, bioavailable 25(OH)D, but not other vitamin D metabolites, was significantly associated with mortality after adjusting for age and serum creatinine (adjusted odds ratio per 1 SD ln [bioavailable 25(OH)D] = 0·16, 95% confidence interval = 0·03-0·85).
  
  
  CONCLUSIONS
  Bioavailable 25(OH)D could have a role as a biomarker or mediator of adverse outcomes among patients with established AKI.
authors: Division of Nephrology, Columbia University Medical Center, New York, NY, USA. deleaf@partners.org
authors: David E
authors: DE
authors: Leaf
authors: Sushrut S
authors: SS
authors: Waikar
authors: Myles
authors: M
authors: Wolf
authors: Serge
authors: S
authors: Cremers
authors: Ishir
authors: I
authors: Bhan
authors: Leonard
authors: L
authors: Stern
mesh_terms: D015650:24,25-Dihydroxyvitamin D 3 / Q000097:blood*; D058186:Acute Kidney Injury / Q000097:blood* / Q000401:mortality; D015415:Biomarkers / Q000097:blood; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D006769:Hospitals, General; D006801:Humans; D007362:Intensive Care Units; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D012016:Reference Values; D015996:Survival Rate; D062606:Tertiary Care Centers; D013997:Time Factors; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014809:Vitamin D-Binding Protein / Q000097:blood*
chemical_list: D015415:Biomarkers; C000717427:FGF23 protein, human; D014809:Vitamin D-Binding Protein; D014807:Vitamin D; D015650:24,25-Dihydroxyvitamin D 3; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23; C104450:25-hydroxyvitamin D