Influence of anticalcineurinic therapy in plasma homocysteine levels of renal transplant recipients: a prospective study

Hyperhomocysteinemia is an independent factor for cardiovascular disease. Renal function and folate level are important determinants of total plasma homocysteine levels. The influence of anticalcineurin drugs on homocysteine levels is controversial. The aims of the study were: (1) to analyze changes in homocysteine levels after the first year of 73 renal transplants and (2) to determine the influence of immunosuppressive anticalcineurin drug therapy on fasting homocysteine concentrations. We examined homocysteine, serum creatinine, folate, and vitamin B12 concentrations immediately after transplant, at 6 months, and after 12 months from renal transplant. Also, MTHFRC677T polymorphism was investigated. Tacrolimus was administered in 28 patients and cyclosporine in 45. Homocysteine levels decreased from 28.41+/-13.71 micromol/L to 18.59+/-8.31 micromol/L after 6 months and to 17.13+/-7.06 micromol/L after 1 year. No relationship was found between homocysteine and folate levels. When anticalcineurin drugs were considered, the homocysteine levels in patients treated with tacrolimus was lower than that in patients treated with cyclosporine at month 6 after transplant (16+/-7.4 micromol/L vs 20.1+/-8.5 micromol/L, P=.03) and after 1 year (15+/-7.6 micromol/L vs 18.4+/-6.4 micromol/L, P=.04). Serum creatinine levels followed the same evolution: they were lower in patients treated with tacrolimus at 6 months (1.35+/-0.36 mg/dL vs 1.57+/-0.45 mg/dL, P=.03) and to a lesser extent at 1 year after renal transplant (1.38+/-0.35 mg/dL vs 1.54+/-0.45 mg/dL, P=.09). The homocysteine value closely related with serum creatinine in both groups. In conclusion, 1 year posttransplant, the homocysteine level was lower among patients treated with tacrolimus, the cohort that also showed the lower serum creatinine concentrations.