title: Association of 25-hydroxyvitamin D with anemia risk in patients scheduled for cardiac surgery.
abstract: BACKGROUND
  There is emerging data that vitamin D plays a role in erythropoiesis. Low 25-hydroxyvitamin D (25OHD) levels may therefore be a risk factor for anemia in patients scheduled for cardiac surgery.
  
  
  METHODS
  We investigated 4428 consecutive cardiac surgical patients to determine an association between anemia (hemoglobin concentration <12.5 g/dL, 27.1% of the study cohort) and circulating 25OHD.
  
  
  RESULTS
  In patients with severe vitamin D deficiency (25OHD < 12.5 nm), mean hemoglobin concentrations were 0.80 g/dL lower compared with patients with adequate 25OHD levels (50.0-100 nm). Hemoglobin levels were not significantly different at 25OHD levels above 100 nm compared with 50.0-100 nm. In multivariable-adjusted logistic regression analyses, the odds ratios for anemia of the groups with severe and moderate vitamin D deficiency (12.5-29.9 nm) were 1.70 (95% CI:1.09-2.63) and 1.41 (95% CI:1.02-1.96), respectively, compared with patients who had circulating 25OHD levels of 75-100 nm. Prevalence of deficient circulating 25OHD levels was highest in anemia of chronic kidney disease.
  
  
  CONCLUSIONS
  This cross-sectional study demonstrates an independent association between vitamin D status and anemia risk with optimal 25OHD levels of 75-100 nm. Randomized controlled trials are needed to clarify whether this association is causal.
authors.affiliation: Clinic for Thoracic and Cardiovascular Surgery, Heart and Diabetes Center North Rhine-Westphalia, Ruhr University Bochum, Bad Oeynhausen, Germany.
authors.forename: Armin
authors.initials: A
authors.lastname: Zittermann
authors.affiliation: Institute for Laboratory and Transfusion Medicine, Heart and Diabetes Center North Rhine-Westphalia, Ruhr University Bochum, Bad Oeynhausen, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Kuhn
authors.affiliation: Institute for Laboratory and Transfusion Medicine, Heart and Diabetes Center North Rhine-Westphalia, Ruhr University Bochum, Bad Oeynhausen, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Dreier
authors.affiliation: Institute for Laboratory and Transfusion Medicine, Heart and Diabetes Center North Rhine-Westphalia, Ruhr University Bochum, Bad Oeynhausen, Germany.
authors.forename: Cornelius
authors.initials: C
authors.lastname: Knabbe
authors.affiliation: Clinic for Thoracic and Cardiovascular Surgery, Heart and Diabetes Center North Rhine-Westphalia, Ruhr University Bochum, Bad Oeynhausen, Germany.
authors.forename: Sylvana
authors.initials: S
authors.lastname: Prokop
authors.affiliation: Clinic for Thoracic and Cardiovascular Surgery, Heart and Diabetes Center North Rhine-Westphalia, Ruhr University Bochum, Bad Oeynhausen, Germany.
authors.forename: Jan F
authors.initials: JF
authors.lastname: Gummert
authors.affiliation: Clinic for Thoracic and Cardiovascular Surgery, Heart and Diabetes Center North Rhine-Westphalia, Ruhr University Bochum, Bad Oeynhausen, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Börgermann
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000150:complications / Q000378:metabolism* / Q000473:pathology; D006348:Cardiac Surgical Procedures; D003324:Coronary Artery Disease / Q000150:complications / Q000378:metabolism* / Q000473:pathology; D003430:Cross-Sectional Studies; D004920:Erythropoiesis / Q000502:physiology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012189:Retrospective Studies; D012307:Risk Factors; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000378:metabolism; D014808:Vitamin D Deficiency / Q000150:complications / Q000378:metabolism* / Q000473:pathology
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: 25-hydroxyvitamin D; Vitamin D; anemia; cardiac surgery; hemoglobin