title: High homocysteine, low folate, and low vitamin B6 concentrations: prevalent risk factors for vascular disease in heart transplant recipients.
abstract: BACKGROUND
  A high plasma homocysteine concentration is a risk factor for atherosclerosis and thrombosis, which are major causes of morbidity and mortality in heart transplant patients. High homocysteine concentrations may be caused by lower folate and vitamin B6 levels. We hypothesized that these patients might have high homocysteine concentrations and low levels of folate and vitamin B6, which could contribute to the development of vascular complications.
  
  
  METHODS
  Total fasting plasma homocysteine was measured in 189 cardiac transplant recipients and in healthy controls, as were concentrations of folate, vitamin B12, vitamin B6, and creatinine.
  
  
  RESULTS
  Homocysteine concentrations were higher in recipients than controls (19.1+/-13.0 vs. 11.0+/-3.0 micromol/L, P<0.01), and hyperhomocysteinemia (>90th percentile for controls, 14.6 micromol/L) was seen in 68% of recipients (P<0.01). Folate and vitamin B6 concentrations were lower (5.9+/-4.2 vs. 7.9+/-4.2 pmol/L and 40+/-25 vs. 84+/-77 nmol/L, respectively; P<0.01 for both). Folate and vitamin B6 deficiencies were seen in 10.8% and 17.91% of recipients, respectively (P<0.01). Hyperhomocysteinemia was more frequent in patients with vascular complications after transplantation than in those without (79.2% vs. 63.8%, P<0.05).
  
  
  CONCLUSIONS
  Elevated plasma homocysteine and deficiencies of folate and vitamin B6 are common in transplant recipients. A high homocysteine concentration was more common in patients with vascular complications. Prospective studies are now required to evaluate the role of these abnormalities as risk factors for the atherothrombotic complications of transplantation.
authors.affiliation: Department of Internal Medicine, The Cleveland Clinic Foundation, Ohio 44195, USA.
authors.forename: A
authors.initials: A
authors.lastname: Gupta
authors.forename: A
authors.initials: A
authors.lastname: Moustapha
authors.forename: D W
authors.initials: DW
authors.lastname: Jacobsen
authors.forename: M
authors.initials: M
authors.lastname: Goormastic
authors.forename: E M
authors.initials: EM
authors.lastname: Tuzcu
authors.forename: R
authors.initials: R
authors.lastname: Hobbs
authors.forename: J
authors.initials: J
authors.lastname: Young
authors.forename: K
authors.initials: K
authors.lastname: James
authors.forename: P
authors.initials: P
authors.lastname: McCarthy
authors.forename: F
authors.initials: F
authors.lastname: van Lente
authors.forename: R
authors.initials: R
authors.lastname: Green
authors.forename: K
authors.initials: K
authors.lastname: Robinson
mesh_terms: D001161:Arteriosclerosis / Q000453:epidemiology* / Q000401:mortality; D015415:Biomarkers / Q000097:blood; D003328:Coronary Thrombosis / Q000453:epidemiology* / Q000401:mortality; D005260:Female; D005492:Folic Acid / Q000097:blood*; D005494:Folic Acid Deficiency / Q000150:complications / Q000453:epidemiology; D005500:Follow-Up Studies; D016027:Heart Transplantation / Q000401:mortality / Q000502:physiology*; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D011183:Postoperative Complications / Q000097:blood / Q000453:epidemiology*; D011736:Pyridoxine / Q000097:blood*; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D026681:Vitamin B 6 Deficiency / Q000150:complications / Q000453:epidemiology
chemical_list: D015415:Biomarkers; D006710:Homocysteine; D005492:Folic Acid; D011736:Pyridoxine