Review
Copyright ©The Author(s) 2024.
World J Nephrol. Dec 25, 2024; 13(4): 100268
Published online Dec 25, 2024. doi: 10.5527/wjn.v13.i4.100268
Table 2 Summarizes the studies on vitamin B12 supplementation in dialysis patients (provides a comparison of the different treatment modalities and their effect on homocysteine, methylmalonic acid, and vitamin B12 levels)
Ref.
Endpoint
Treatment
Results
Azadibakshsh et al[94]Effect of high dose oral folic acid and vitamin B12 on homocysteine levelsHigh dose oral folic acid (15 mg/day) + vitamin B12 (1 mg/day)Significant reduction in total homocysteine levels by 30% with a desirable effect on serum folic acid and vitamin B12 levels
Elian and Hoffer[95]Effect of hydroxocobalamin on plasma total homocysteine and methylmalonic acid levels1 mg hydroxocobalamin subcutaneously per week after hemodialysis vs standard treatment (oral folic acid + pyridoxine + vitamin B12)32% reduction in plasma total homocysteine and 19% reduction in methylmalonic acid levels
Papadakis et al[97]Effect of oral vs intravenous vitamin B12 with oral folic acid on homocysteine levelsOral folic acid (1 mg/day) + oral vitamin B12 (600 μg) vs oral folic acid (1 mg/day) + 1mg intravenous vitamin B12Significant reduction in total homocysteine levels with intravenous treatment compared to oral treatment
Chiu et al[98]Effect of intravenous vitamin B12 alone vs intravenous low-dose folic acid alone vs combination of both on homocysteine levels1 mg intravenous vitamin B12 weekly after hemodialysis vs 3 mg intravenous folic acid weekly vs combination of bothIntravenous vitamin B12 alone is as effective as intravenous low-dose folic acid in lowering homocysteine levels with the combination of both having a greater effect
Koyama et al[99]Effect of high dose oral folic acid vs intravenous methylcobalamin vs combination of both on homocysteine levelsHigh dose oral folic acid (15 mg/day) vs 500 mg intravenous methylcobalamin after each hemodialysis vs combination of bothSimilar efficacy of both treatments in reducing homocysteine levels, with greater effect in combination
Kaplan et al[100]Effect of parenteral vitamin B12 alone on homocysteine levelsThree parenteral injections of 1 mg vitamin B12 given at 4-week intervalsSignificant reduction in homocysteine levels and increase in serum B12 levels
Arnadottir and Hultberg[105]Effect of oral vitamin B12 on homocysteine levels and vitamin B12 levels2 mg oral vitamin B12 3 times a week (after each dialysis session) for 6 weeks vs no treatmentSignificant increase in serum vitamin B12 levels in treated group with no significant reduction in homocysteine levels compared to control group
Polkinghorne et al[88]Effect of intramuscular vitamin B12 on homocysteine levels and vitamin B12 levels1 mg intramuscular vitamin B12 monthly for 3 months vs 1 mL saline placebo injectionSignificant increase in serum vitamin B12 levels in treated group with no significant reduction in homocysteine levels compared to placebo group
Hoffer et al[106]Comparison of different intravenous cyanocobalamin dosage regimens on plasma homocysteine1 mg intravenous cyanocobalamin post-dialysis every 28, 14, and 7 days + routine oral vitamin B7- or 14-day intervals had a similar effect on reducing homocysteine concentrations, with 7-day regimen increasing serum B12 the most
Hoffer et al[107]Effect of different formulations of vitamin B12 on serum homocysteine and vitamin B12 levels1 mg intravenous hydroxocobalamin weekly for 8 weeks followed by cyanocobalamin for 8 weeks vs 1 mg intravenous cyanocobalamin weekly for 8 weeks followed by hydroxocobalamin for 8 weeksHydroxocobalamin increased serum vitamin B12 concentrations 40-fold compared to cyanocobalamin which increased them only 10-fold, but both treatments reduced plasma homocysteine concentrations similarly by 33%
Dierkes et al[108]Effect of vitamin B12 in patients with low baseline serum levels (< 180 pmol/L) on homocysteine and methylmalonic acid levels1 mg intravenous cyanocobalamin weekly for 4 weeksReduction in plasma total homocysteine and methylmalonic acid levels by 35% and 48%, respectively