The achievement of normal homocysteinemia in regular extracorporeal dialysis patients.

BACKGROUND: High total homocysteinemia (tHcy) is a vascular risk factor in regular dialysis treatment (RDT) patients. A near normal tHcy has previously been achieved (from 33 +/- 11 to 13 +/- 5 micromol/L) in 23 patients on hemodiafiltration (HDF) by adjusting intravenous (i.v.) supplements of folinic acid, vitamin B12 and B6, gradually during a 2-yr follow-up. Thereafter, the same therapeutic schedule was used for all patients undergoing RDT in our unit to confirm its efficacy on a larger scale. PATIENTS AND METHODS: Patients (n=63, F 34, age 66 +/- 14 yrs, dialytic age 60 +/- 53 months) underwent high UF post-dilutional on-line HDF for at least 6 months. They received i.v. folinic acid 3 mg, vitamin B12 50 microg and vitamin B6 450 mg/wkly. After 4 months, pre- and post-dialytic serum Hcy (n.v. 11 +/- 2 micromol/L), as well as pre-dialytic serum folate (sFA, n.v. 3-17 ng/mL) and vitamin B12 (sB12, n.v. 226-966 pg/mL) were determined. RESULTS: The mean pre-dialytic tHcy fell to within the normal range (from 31 +/- 10 to 12.5 +/- 5 umol/L), it was slightly above the normal limits (19 +/- 2 umol/L) in only 11 patients (17%), whereas the post-dialytic value was normal in all patients (7 +/- 2.5 umol/L). The average values of sFA (25 +/- 10 ng/mL) and sB12 (1500 +/- 320 pg/mL) were approximately twice the normal limits. CONCLUSION: Therefore, HDF appears to remove tHcy efficiently and tHcy is generally normalized by adjusting the dose of vitamin B12, vitamin B6 and folinic acid supplements.