[Homocysteine and its metabolites in chronic renal insufficiency and the effect of a vitamin replacement].
BACKGROUND
Hyperhomocysteinemia has been increasingly recognized as an important risk factor for elevated atherosclerotic vascular disease in chronic renal failure. We measured in patients with chronic renal failure homocysteine and metabolites of its 2 metabolic pathways, transulfuration (cystathionine, cysteine) and remethylation (methionine, methylmalonic acid, 2-methylcitric acid).


METHODS
Eleven patients on conservative treatment (creatinine clearance 10 to 30 ml/min) and 50 chronic uremic subjects on regular hemodialysis were included in the study. Twenty-two of the dialysis patients received daily oral multivitamin supplementation containing 10 mg vitamin B6, 6 micrograms vitamin B12, and 1 mg folic acid during the last year before the study started.


RESULTS
In the hemodialysis group homocysteine levels were higher compared with the patients on conservative treatment. Hemodialysis patients with additional vitamin supplementation showed significantly lower homocysteine levels than those without. The pattern of metabolites was different to these results: all metabolites were higher in hemodialysis patients, too (significant for cysteine and methionine), but vitamin supplementation failed to lower all metabolites.


CONCLUSIONS
Analysis of metabolites additional to homocysteine levels may help to understand different results in evaluation of atherosclerotic risk of hyperhomocysteinemia in chronic renal failure.
Henning
B F
BF
Universitätsklinik Marienhospital Herne, Ruhr-Universität Bochum. walter.zidek@ruhr-univ-bochum
Tepel
M
M
Graefe
U
U
Zidek
W
W
D000328:Adult; D000368:Aged; D001161:Arteriosclerosis / Q000517:prevention & control; D003545:Cysteine / Q000097:blood; D005260:Female; D005492:Folic Acid / Q000627:therapeutic use; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D020138:Hyperhomocysteinemia / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000628:therapy; D008297:Male; D008715:Methionine / Q000097:blood; D008875:Middle Aged; D011736:Pyridoxine / Q000627:therapeutic use; D006435:Renal Dialysis / Q000009:adverse effects*; D012720:Severity of Illness Index; D014805:Vitamin B 12 / Q000627:therapeutic use; D014803:Vitamin B Complex / Q000097:blood / Q000627:therapeutic use*
D006710:Homocysteine; D014803:Vitamin B Complex; D005492:Folic Acid; D008715:Methionine; D003545:Cysteine; D011736:Pyridoxine; D014805:Vitamin B 12