Preliminary Results of the Effect of Treatment of Hyperhomocysteinemia and Its Relationship With Inflammation, Coagulation Status, and Endothelial Function After Renal Transplantation

The aim of this study was to assess the relationship between total plasma homocysteine (tHC) and several markers of endothelial function, coagulation, and pro-inflammatory status in renal transplant recipients. Our own previous study demonstrated the efficacy of folic acid (FA) and vitamin B(12) (B(12)) treatment to reduce tHC. Using 70 stable recipients, 56 of whom showed hyperhomocisteinemia (HHC) (tHC > or = 14 micromol/L) and a control group (n = 14, tHC < 14 micromol/L), we treated 29 patients in the HHC group (10 mg FA and 500 mg B(12) daily) and determined their endothelial function, inflammatory activity, and coagulation status. We assessed plasma levels of von Willebrand Factor and fibrinogen as the prothrombotic profile and C-reactive protein and plasma albumin as inflammation markers. We performed Doppler sonography of the brachial artery to assess endothelial function. The mean value of plasma tHC of 19.05 +/- 3.70 micromol/L before treatment decreased to 13.45 +/- 3.25 micromol/L after 3 months of treatment (P < .001). The vWF was significantly correlated with tHC (P < .05) and was higher in the HHC patients (P < .05). The fibrinogen mean level was also significantly higher in HHC patients (P < .05). The C-reactive protein level was significantly higher and the albumin level was lower among patients with HHC. The endothelium-dependent dilation (EDD) correlated with baseline tHC (P < .05). In preliminary data we observed that homocysteine-lowering therapy may provide cardiovascular protection by enhancing endothelial function, limiting oxidative stress, and reducing procoagulation status.

Autosomal-dominant polycystic kidney disease: high prevalence of graft loss for death-related malignancies and cardiovascular risk factors

Autosomal-dominant polycystic kidney disease (ADPKD) is a systemic disease with multiple extrarenal manifestations. It accounts for 7% to 11% of patients receiving dialysis or renal transplantation (RT) for end-stage renal disease (ESRD) in Europe. We analyzed retrospectively the causes of death, the prevalence of cardiovascular risk factors (CVRF) and the patient and graft survivals in 62 consecutive ADPKD patients who received 63 cadaveric grafts (29 men and 34 women), of the 600 RTs performed between 1980-2001. The diagnosis of ADPKD was established by family history and ultrasound techniques. At present, 50 patients (79.4%) have functioning grafts, with a mean follow-up of 84.7 months (range, 12-255), and 13 patients have lost their grafts. The main cause of failure was patient death with a functioning graft (9 cases). Malignancies occurred in 5 patients, including 2 lymphomas, 1 renal carcinoma, 1 pancreas sarcoma, and 1 lung cancer associated with infection. Three patients died of cardiocerebrovascular events, and 1 patient of pneumonia. One patient lost the graft after decreasing the immunosuppression for an obstructing colon cancer. Three additional patients now on dialysis lost their grafts due to chronic rejection in 2 cases and primary nonfunction in 1 case. The prevalence of cardiovascular risk factors among the 50 patients with functional grafts were: hypertension, 70%; hypercholesterolemia, 62%; hyperhomocysteinemia, 30%; hyperfibrinogenemia, 68%; increased lipoprotein (a), 18%; microalbuminuria, 22%; hyperuricemia, 48%; hyperparathyroidism, 24%; overweight status, 24%; and nonlethal myocardial infarction, 10%. We conclude that ADPKD patients have good graft and patient survivals, and that the presence of malignancy is the main cause of death and graft failure at our center.

Treatment of hyperhomocysteinemia after renal transplantation

INTRODUCTION

Several epidemiologic prospective studies have provided strong evidence that hyperhomocysteinemia (HHC) is a risk factor for cardiovascular disease (CVD) due to its role in producing endothelial damage due to oxidation stress. Several studies show that combined folic acid (FA) and vitamin B12 (B12) treatment decreases fasting total homocysteine (HC) levels in renal transplant recipients (RTR). The aim of the study was to determine the efficacy and safety during one year of combined FA and B12 treatment in 89 RTR, as well as the relationship between HHC with other known risk factors for CVD and the intrinsic characteristics of the transplantation.

METHODS

Among 193 RTR in whom we determined the baseline levels of HC, FA, B12, creatinine, and CV risk factors, 81 had normal (HC < 14 micromol/L) and 112 elevated (HC > or = 14 micromol/L) HC levels, 89 of whom were included in a treatment group (23 nontreated). Analytic measures were performed at baseline and 1, 3, and 12 months.

RESULTS

We observed a decrease in HC levels among the treatment group (P<.05) after 12 months without differences in the other groups. There were no differences in age, hypertension, hypercholesterolemia, smoking, presence of diabetes, or type of immunosuppression between the groups. There was a significant correlation between basal creatinine and HC level (P<.05). A higher prevalence of CVD was observed in the HHC group (P<.05).

CONCLUSION

HHC is associated with worse renal function and a higher prevalence of CVD. FA and B12 treatment normalize HC levels, representing a safe treatment that could improve the long-term vascular prognosis of RTR.