Hyperhomocysteinaemia therapy in haemodialysis patients: folinic versus folic acid in combination with vitamin B6 and B12.
BACKGROUND
In a recent uncontrolled retrospective report we suggested that the long-term supplementation of high-dose, i.v. folinic acid combined with high-dose i.v. pyridoxine was highly effective in correcting plasma total homocysteine (tHcy) concentrations in haemodialysis patients. To confirm these findings, we conducted a randomized, controlled trial aimed at evaluating whether i.v. or oral folinic acid provided improved tHcy-lowering efficacy in haemodialysis patients compared with oral folic acid.


METHODS
In a 6-month prospective, randomized, controlled trial, 60 chronic haemodialysis patients, matched for age, gender, dialysis duration, and average screening pre-treatment-fasting tHcy levels, were given either 50 mg/week of i.v. calcium folinate (group 1), 50 mg/week of oral calcium folinate (group 2), or 45 mg/week oral folic acid (group 3). All 60 patients also received 750 mg/week of i.v. vitamin B6 and 3 mg/week of oral vitamin B12.


RESULTS
Fasting tHcy decreased significantly and to a similar extent in the three groups after 2 months of treatment and remained stable at 4 and 6 months (16.6+/-3.5, 18.3+/-4, and 19.1+/-3.1, in groups 1, 2, and 3, respectively, P=NS). Mean percentage reduction at 6 months was also similar in the three treatment groups (46, 43, and 42% in groups 1, 2, and 3, respectively, P=NS).


CONCLUSIONS
These findings show that the tHcy-lowering effects of high-dose i.v. folinic acid, oral folinic acid, or oral folic acid were comparable, suggesting that the hyperhomocysteinaemia observed in haemodialysis patients is not due to abnormal folate metabolism. Furthermore, they are compatible with the view that other abnormalities are also involved in the impaired clearance of homocysteine in uraemic patients.
Ducloux
Didier
D
Division of Nephrology, Biochemistry B Laboratory, CHU St Jacques, Besançon, France.
Aboubakr
Abdelfatah
A
Motte
Gérard
G
Toubin
Gérard
G
Fournier
Véronique
V
Chalopin
Jean-Marc
JM
Drüeke
Tilman
T
Massy
Ziad A
ZA
D000284:Administration, Oral; D000368:Aged; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage / Q000627:therapeutic use*; D006397:Hematinics / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D020138:Hyperhomocysteinemia / Q000188:drug therapy* / Q000209:etiology; D007275:Injections, Intravenous; D002955:Leucovorin / Q000008:administration & dosage / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D006435:Renal Dialysis / Q000009:adverse effects; D013997:Time Factors; D014805:Vitamin B 12 / Q000008:administration & dosage / Q000627:therapeutic use*; D025101:Vitamin B 6 / Q000008:administration & dosage / Q000627:therapeutic use*
D006397:Hematinics; D025101:Vitamin B 6; D005492:Folic Acid; D014805:Vitamin B 12; D002955:Leucovorin