title: 1,25-Dihydroxyvitamin D fluctuations in cardiac surgery are related to age and clinical outcome*.
abstract: OBJECTIVE
  To investigate the interrelationship between cardiac surgery, age, circulating concentrations of the vitamin D hormone 1,25-dihydroxyvitamin D, and clinical outcome.
  
  
  METHODS
  Prospective, monocentric, two-arm parallel study.
  
  
  METHODS
  Tertiary Heart and Diabetes Center in the Federal State of North Rhine-Westphalia, Germany.
  
  
  METHODS
  Twenty-nine cardiac surgical patients aged ≤ 65 yrs and 30 patients ≥ 75 yrs.
  
  
  METHODS
  We assessed 1,25-dihydroxyvitamin D and other biochemical parameters of mineral metabolism (calcium, phosphate, 25-hydroxyvitamin D, and parathyroid hormone), various inflammatory markers (C-reactive protein, interleukin-6 and 8), and different immunological parameters (CD4 and CD8 cells, monocyte HLA-DR expression). We collected blood samples preoperatively, immediately after surgery, and on postoperative days 1, 5, and 30. In addition, we assessed adverse outcome until discharge as a composite of myocardial infarction, low cardiac output syndrome, infection, stroke, or in-hospital death.
  
  
  RESULTS
  There were significant transient cardiac surgery-related fluctuations in 1,25-dihydroxyvitamin D and the aforementioned parameters of mineral metabolism, inflammation, and immune status. Compared to younger patients, older patients had consistently lower 1,25-dihydroxyvitamin D and phosphate levels (p = .013 and p = .036, respectively) and significantly higher interleukin 6 and 8 levels (p = .008 and p < .001, respectively). Circulating 1,25-dihydroxyvitamin D was directly related to glomerular filtration rate (R(2) = .227; p < .001) and inversely related to interleukin 6 (R(2) = .105; p = .012). The rate of adverse outcome tended to be higher in older than in younger patients (20.0% vs. 3.5%; p = .081). In risk score-adjusted logistic regression analysis, adverse outcome risk decreased by 7.7% (SE: 3.7%) for each pmol/L increment in 1,25-dihydroxyvitamin D (p = .037).
  
  
  CONCLUSIONS
  Circulating 1,25-dihydroxyvitamin D levels fluctuate in relation to cardiac surgery. Low 1,25-dihydroxyvitamin D levels are associated with inflammatory processes and age-related differences in clinical outcome. Future studies should determine whether therapies aimed at treating low 1,25-dihydroxyvitamin D levels can improve the outcome in older cardiac surgery patients.
authors.affiliation: Clinic for Thoracic and Cardiovascular Surgery, Heart and Diabetes Center North Rhine-Westphalia, Ruhr University Bochum, Georgstrasse 11Bad Oeynhausen, Germany. jboergermann@hdz-nrw.de
authors.forename: Jochen
authors.initials: J
authors.lastname: Börgermann
authors.forename: Kanstantsin
authors.initials: K
authors.lastname: Lazouski
authors.forename: Joachim
authors.initials: J
authors.lastname: Kuhn
authors.forename: Jens
authors.initials: J
authors.lastname: Dreier
authors.forename: Michael
authors.initials: M
authors.lastname: Schmidt
authors.forename: Thomas
authors.initials: T
authors.lastname: Gilis-Januszewski
authors.forename: Cornelius
authors.initials: C
authors.lastname: Knabbe
authors.forename: Jan F
authors.initials: JF
authors.lastname: Gummert
authors.forename: Armin
authors.initials: A
authors.lastname: Zittermann
mesh_terms: D000367:Age Factors; D000368:Aged; D002097:C-Reactive Protein / Q000032:analysis; D016516:CD4-CD8 Ratio; D002118:Calcium / Q000097:blood; D002303:Cardiac Output, Low; D001026:Coronary Artery Bypass; D005260:Female; D005919:Glomerular Filtration Rate; D006684:HLA-DR Antigens / Q000378:metabolism; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D007362:Intensive Care Units; D015850:Interleukin-6 / Q000097:blood; D016209:Interleukin-8 / Q000097:blood; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism; D009203:Myocardial Infarction / Q000453:epidemiology; D017063:Outcome Assessment, Health Care; D010281:Parathyroid Hormone / Q000097:blood; D010710:Phosphates / Q000097:blood; D011446:Prospective Studies; D013530:Surgical Wound Infection / Q000453:epidemiology; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D006684:HLA-DR Antigens; D015850:Interleukin-6; D016209:Interleukin-8; D010281:Parathyroid Hormone; D010710:Phosphates; D014807:Vitamin D; C097949:1,25-dihydroxyvitamin D; D002097:C-Reactive Protein; C104450:25-hydroxyvitamin D; D002118:Calcium