title: Usefulness of plasma vitamin B(6), B(12), folate, homocysteine, and creatinine in predicting outcomes in heart transplant recipients.
abstract: Atherothrombotic complications are frequently seen in patients undergoing heart transplantation. These patients have high plasma total homocysteine concentrations associated with lower folate and vitamin B(6) levels. The relation between these metabolic abnormalities and the development of vascular complications, however, remains unclear. Fasting plasma total homocysteine, folate, vitamin B(12), vitamin B(6), and creatinine were measured in 160 cardiac transplant recipients who were followed for a mean duration of 28 +/- 9 months after blood draw (mean 59 +/- 28 months after transplant). Cardiovascular events and causes of mortality were determined and Cox proportional-hazards regression analysis was used to identify the independent predictors for cardiovascular events and mortality. Twenty-five patients developed cardiovascular events and 17 died (11 cardiovascular deaths). Mean +/- SD total homocysteine value was 18.4 +/- 8.5 (range 4.3 to 63.5 micromol/L). Hyperhomocysteinemia (> or =15 micromol/L) was seen in 99 patients (62%). Levels were no different in patients with or without cardiovascular complications/death (16.8 +/- 6.2 vs 18.9 +/- 9 micromol/L, p = 0.4). However, vitamin B(6) deficiency was seen in 21% of recipients with and in 9% without cardiovascular complications/death (p = 0.05). The relative risk for cardiovascular events, including cardiovascular death, increased 2.7 times (confidence interval 1.2 to 5.9) for B(6) levels < or =20 nmol/L compared with those with normal B(6) levels (p = 0.02). Thus, hyperhomocysteinemia is common in transplant recipients but may have no causal role in the atherothrombotic vascular complications of transplantation. Deficiency of vitamin B(6), however, may predict adverse outcomes, suggesting a possible role for supplementation with this vitamin.
authors.affiliation: Department of Cardiology, The Cleveland Clinic Foundation, Cleveland, Ohio, USA.
authors.forename: Maher
authors.initials: M
authors.lastname: Nahlawi
authors.forename: Niranjan
authors.initials: N
authors.lastname: Seshadri
authors.forename: Navdeep
authors.initials: N
authors.lastname: Boparai
authors.forename: Arabi
authors.initials: A
authors.lastname: Naso
authors.forename: Donald W
authors.initials: DW
authors.lastname: Jacobsen
authors.forename: Patrick
authors.initials: P
authors.lastname: McCarthy
authors.forename: James
authors.initials: J
authors.lastname: Young
authors.forename: Killian
authors.initials: K
authors.lastname: Robinson
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D003404:Creatinine / Q000097:blood*; D005260:Female; D005492:Folic Acid / Q000097:blood*; D016027:Heart Transplantation / Q000009:adverse effects; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis; D013927:Thrombosis / Q000097:blood / Q000209:etiology*; D014805:Vitamin B 12 / Q000097:blood*; D025101:Vitamin B 6 / Q000097:blood*
chemical_list: D015415:Biomarkers; D006710:Homocysteine; D025101:Vitamin B 6; D005492:Folic Acid; D003404:Creatinine; D014805:Vitamin B 12