Cobalamin dose regimen for maximum homocysteine reduction in end-stage renal disease

Comparative effects of hydroxocobalamin and cyanocobalamin on plasma homocysteine concentrations in end-stage renal disease

“…Having recently discovered that CC raises serum cobalamin concentrations of hemodialysis patients far less than HC [27], we carried out the present study to determine whether the higher serum cobalamin concentration associated with HC translates into more potent Hcy reduction. Our results confirm that intravenous HC raises serum cobalamin concentrations approximately 5 times higher than CC does in patients with ESRD.…”

“…The analysis was by high-performance liquid chromatography with fluorescence detection as described earlier [25]. Serum cobalamin and folate concentrations were analyzed after appropriate dilution by automated chemiluminescent immunoassay (Immulite, Diagnostic Products, Los Angeles, Calif) as in our earlier studies [25,27]. The normal ranges for this assay are 180 to 660 pmol/L for cobalamin and 6 to 40 nmol/L for folate.…”

“…Three randomized prospective clinical trials [25][26][27], 2 of them by us [25,27], indicate that the addition of parenteral hydroxocobalamin (HC) or methylcobalamin to an oral regimen of folic acid and other B vitamins can reduce plasma tHcy concentrations of maintenance hemodialysis patients 30% to 50% below the level attained with the oral vitamins alone. Owing to its limited bioavailability [28], even high-dose daily oral cyanocobalamin (CC) increases serum cobalamin concentrations of patients with ESRD by 3-fold at most [15,19,29] and reduces plasma tHcy concentrations very modestly [15] if at all [23,30].…”

“…It would be natural to attribute the potency of parenteral cobalamin to the very high serum concentrations uniquely attainable with this mode of administration. We were recently surprised to find that an 8-week course of weekly intravenous CC increased serum cobalamin concentrations only to approximately 7 times the upper normal value [27]. This raised the possibility that different forms of cobalamin might reduce plasma tHcy with different potency.…”

Pharmacological Dose of Vitamin B12 Is as Effective as Low-Dose Folinic Acid in Correcting Hyperhomocysteinemia of Hemodialysis Patients

“…[11][12][13] Pharmacological dose of Vit B12, in combination with folic acid, has been reported to be effective in lowering the plasma Hcy levels. [13][14][15][16] However, the effect of pharmacologic does of Vit B12 alone was not clear. Folic acid supplement with dose as low as 1.1mg/week, even in combination with pharmacologic dose of Vit B12, had no effect on hyperhomocysteinemia correction.…”