Many years ago vitamin B therapy was found to improve anemia in patients with deficiencies of B vitamins “Wills L “. End-stage renal disease patients on hemodialysis treatment frequently have vitamin B deficiency because of malnutrition and losses of vitamins B into the dialysate. Although vitamin B therapy should improve anemia in these patients, only a few uncertain data “Righetti M ” have been published. A retrospective study analyzed the effects of vitamin B therapy on anemia, homocysteine, and consumption of erythropoiesis stimulating agents in hemodialysis patients. The results suggested that hyperhomocysteinemia may up-regulate the erythropoiesis process, which is decreased in end-stage renal disease patients, by acting on receptors implicated in the erythropoiesis pathway. In view of these results we performed a prospective study in our hemodialysis patients.
A prospective, 12-months, study was performed in 26 hemodialysis patients. The subjects had stable haemoglobin values during a 3-month observational period. After this phase, oral vitamin B supplementation, consisting of 5 mg folic acid, 250 mg vitamin B1, 250 mg vitamin B6, 500 mcg vitamin B12 weekly were consumed during a 9 month period. Haemoglobin, doses of erythropoiesis stimulating agents, and the erythropoiesis stimulating agents resistivity index were evaluated every month, while folate, vitamin B12, and homocysteine were measured at baseline and at the end of the study.
The results showed that haemoglobin levels (11.2 ± 0.2 vs. 11.2 ± 0.1 g/dl, p = n.s.), doses of erythropoiesis stimulating agents (37128 ± 4851 vs. 36244 ± 4339 IU/month) and the erythropoiesis stimulating agents resistivity index (ESARI: 13.4 ± 1.9 vs. 12.7 ± 1.5 IU per week/Kg/Hgb, p = n.s.) were similar during the observational period and during vitamin B therapy. These results show that physiological doses of B vitamin do not lower doses of erythropoiesis stimulating agents in hemodialysis patients with normal serum folate levels. The previous observation, showing a significant inverse association between baseline total plasma homocysteine levels and the erythropoiesis stimulating agents resistivity index, was confirmed in this study (figure 1). Patients were divided in two subgroups, according to baseline total plasma homocysteine values, as shown in the table. Hemodialysis patients in the subgroup with high baseline total plasma homocysteine levels had a large decrease of homocysteine values, from 61 to 34 micromoles per litre (44%), but an increased consumption of erythropoiesis stimulating agents and an increased erythropoiesis stimulating agents resistivity index. Hemodialysis patients with normal or slightly high baseline total plasma homocysteine levels had a small decrease of homocysteine values, from 23 to 20 micromoles per litre (13%), and a reduction of erythropoiesis stimulating agents consumption and the erythropoiesis stimulating agents resistivity index were observed.
These results confirm that severe hyperhomocysteinemia lowers the dose of erythropoiesis stimulating agents, prescribed for improving anemia. Furthermore, the results suggest that homocysteine-lowering vitamin B therapy in patients with severe hyperhomocysteinemia may increase the dose of erythropoiesis stimulating agents instead of decreasing erythropoiesis stimulating agents consumption as seen in patients with normal or mildly increased homocysteine levels.