Long-term folic acid (but not pyridoxine) supplementation lowers elevated plasma homocysteine level in chronic renal failure
Chauveau, P.; Chadefaux, B.; Coudé, M.; Aupetit, J.; Kamoun, P.; Jungers, P.
Mineral and Electrolyte Metabolism 22(1-3): 106-109
1996
ISSN/ISBN: 0378-0392 PMID: 8676798 Document Number: 459187
The effects of sequential supplementation with pyridoxine (70 mg/day) and folic acid (10 mg/day) for two 3-month periods were examined in 37 nondialysed renal failure patients (29 male) with creatinine clearance (CCr) ranging from 10 to 80 ml/min, whose plasma vitamin B12 and folate level was in the normal range. Mean (+or-SD) baseline plasma total homocysteine (Hcy) was 14.9+or-5.2, 16.5+or-5.1 and 26.1+or-12.1 micro mol/litre (upper limit in 45 healthy controls 14.1 micro mol/litre) in patients with CCr 40-80, 20-40 and <20 ml/min, respectively. Following pyridoxine, Hcy did not significantly decrease whereas following folic acid Hcy decreased to 9.9+or-2.9 (-33% vs. baseline), 10.3+or-3.4 (-37%) and 15.4+or-5.5 (-40%), respectively (Student's paired t test, P<0.001) in the 3 groups. It is concluded that folate (but not pyridoxine) supplementation is effective in lowering elevated plasma Hcy in chronic renal failure patients, thus suggesting that enhancing Hcy remethylation pathway may overcome hyperhomocysteinaemia in such patients. In view of the potential atherogenic effects of hyperhomocysteinaemia, long-term folate supplementation should be considered in uraemic patients.