Effects of alternate supplementation with Folic acid and Vitamin B12 on Homocysteine plasma levels in Hemodialysis patients.

Background. Treatment with folic acid and Vitamin B12 appears to be effective to reduce total plasma homocysteine levels, but it is unknown whether vitamin B12 alone reduces tHcy values in patients with normal levels of vitamin B12. The aim of the present study was to explore the effect of the individual supplementation with folic acid or vitamin B12 on tHcy concentrations and MTHFR polymorphism in HD patient and correlate tHcy concentrations with MTHFR genotype before and after vitamins supplementation. Methods. Two hundred unselected patients (119 men) were recruited from the “Umberto I” Hospital (Frosinone, Italy) and from Dialysis Unit of University Hospital “Tor Vergata”. These patients have been randomized blindly into two groups of one hundred subjects each. Unfortunately, during the study 36 patients of the first group and 16 of the second group died.The 1st group was treated initially with vitamin B12 for two months and with folic acid for the following two months. The 2nd group was treated initially with folic acid and then with Vitamin B12. A wash out period of 2 months followed the treatment in both groups. Results. tHcy concentrations decreased in both groups following the alternate vitamins therapy, and the decrease is genotype-dependent. The decrease is more accentuated for the T/T genotype (p<0.05) and is more significant when the treatment was started with folic acid (p<0.01). Conclusions. The alternate vitamins treatment demonstrated for the first time the importance of folate therapy and the secondary contribution of vitamin B12 in lowering tHcy in HD patients.