Vitamin supplementation reduces the progression of atherosclerosis in hyperhomocysteinemic renal transplant recipients

Abstract number: OC162

Marcucci^* R., Zanazzi† M., Bertoni† E., Salvadori† M., Castellani^* S., Fedi^* S., Gensini^* F., Giusti^* B., Pepe^* G., Prisco^* D., Abbate^* R., Gensini^* G. F.

†Renal Unit, Azienda Ospedaliera Careggi, Italy ^*University of Florence, Italy;

Cardiovascular diseases are the main causes of morbidity and mortality in kidney transplant recipients. Among these patients, we previously demonstrated a high prevalence of hyperhomocysteinemia which might account for their higher cardiovascular risk. Aim of our study was to document, in hyperhomocysteinemic renal transplant recipients, the effect of vitamin supplementation on carotid intima-media thickness (cIMT), an early sign of atherosclerosis which has been associated with risk factors for cardiovascular disease such as blood pressure, diabetes and smoking. Fifty-six stable hyperhomocysteinemic renal transplant recipients were randomly assigned to either vitamin supplementation (folic acid 5 mg/day; vitamin B₆ 50 mg/ day; vitamin B₁₂ 400 µ g) (GROUP A) or placebo treatment (GROUP B). All subjects underwent cardiovascular risk factor assessment, including fasting homocysteine (Hcy) levels assay, and high resolution B-mode ultrasound to measure IMT of common carotid arteries, before and after 6 months of vitamin supplementation. Three patients of group A discontinued the therapy and were excluded from the study. No side-effects were observed. The prevalence of the common cardiovascular risk factor in the two groups was similar; all patients were on a triple immunosuppressive therapy. Fasting Hcy levels markedly decreased in group A after treatment (29.7±16 µmol L^-1 vs. 9.2±1.9 µmol L^-1; P < 0.0001), whereas no significant changes were observed in group B (22.8±5.4 µmol L^-1 vs. 22±5.2 µmol L^-1; P = ns). In group A, cIMT significantly decreased after treatment (0.95±0.20 mM vs. 0.64±0.17 mM: P < 0.0001). All but one patient showed a reduction of cIMT and the mean percentage of cIMT decrease was -32.2±12.9. In hyperhomocysteinemic patients without vitamin supplementation (group B) we documented a significantly progression in cIMT after 6 months (0.71±0.16 mM vs. 0.87±0.19 mM; P < 0.05). In 19/28 subjects we observed an increase in cIMT, and in 9/28 the cIMT was unmodified. The mean percentage of cIMT increase was +23.3±21.1. In conclusion, our results demonstrate a beneficial effect of the treatment of hyperhomocysteinemia by vitamin supplementation on an early sign of atherosclerosis in a group of renal transplant recipients.