Folic acid and vitamin B12 are more effective than vitamin B6 in lowering fasting plasma homocysteine concentration in patients with coronary artery disease

Abstract

Objective: To investigate whether vitamin B 6 supplementation had a beneficial effect on lowering fasting plasma homocysteine concentrations in coronary artery disease (CAD) patients. Design: A single-blind intervention study. Setting: The study was performed at the Taichung Veterans General Hospital, the central part of Taiwan. Subjects: A total of 50 subjects were identified by cardiac catheterization to have at least 70% stenosis of one major coronary artery. In all, 42 patients successfully completed this study. Interventions: Patients were randomly assigned to one of five groups and treated with a daily dose of placebo (n ¼ 8), 5 mg vitamin B 6 (n ¼ 8), 10 mg vitamin B 6 (n ¼ 8), 50 mg vitamin B 6 (n ¼ 9), or 5 mg folic acid combined with 0.25 mg vitamin B 12 (n ¼ 9) for 12 weeks. Main outcome measures: Nutrient intakes were recorded by using 24-h diet recalls when patients returned to the cardiology clinic before the intervention (week 0) and at week 12. Vitamin B 6 status was assessed by direct measures (plasma pyridoxal 5 0 -phosphate) and indirect measures (erythrocyte alanine and aspartate aminotransaminase activity coefficient). Fasting plasma homocysteine, serum folic acid, and vitamin B 12 were measured. Results: Fasting plasma homocysteine concentration did not respond to high or low doses of vitamin B 6 when compared with a placebo treatment after 12 weeks of supplementation. The mean fasting plasma homocysteine concentration, however, decreased significantly after 12 weeks of folic acid combined with vitamin B 12 supplementation (P ¼ 0.047). Further, within group, mean fasting plasma homocysteine concentration was nonsignificantly increased by 25.5, 16.2, and 18.3% in placebo, 10 mg/day and 50 mg/day vitamin B 6 supplemented groups, respectively; whereas folic acid combined with vitamin B 12 supplementation significantly reduced fasting plasma homocysteine concentration by 32% (Po0.001). Conclusions: Our results indicate that vitamin B 6 supplementation alone is less effective than folic acid combined with vitamin B 12 in lowering plasma homocysteine concentrations in CAD patients.

Plasma homocysteine level is elevated in patients on isotretinoin therapy for cystic acne: A prospective controlled study

“…There are clinical data showing that fasting plasma Hcy was markedly increased in patients with folate (16)(17)(18)(19) or vitamin B12 deficiency (16,18), and there are studies (20)(21)(22)(23)(24)(25)(26) about the role of vitamin B12, folate, and vitamin B12 supplementation on Hcy concentrations. A meta-analysis of the randomized (22) showed that folic acid (5 mg) combined with vitamin B12 (0.25 mg) supplementation significantly reduced fasting plasma Hcy concentration in CAD patients.…”

“…A meta-analysis of the randomized (22) showed that folic acid (5 mg) combined with vitamin B12 (0.25 mg) supplementation significantly reduced fasting plasma Hcy concentration in CAD patients. Schulpis et al (11) carried out the first study about the evaluation of plasma Hcy levels in 28 patients on Iso therapy for CA.…”

“…As there may be vitamin deficiencies in clinically healthy appearing individuals, it would be helpful if the vitamin levels are known before Iso treatment is started. Because many studies (9,(20)(21)(22)25) concluded that vitamin B12 and folic acid had a significant effect on the reduction of Hcy levels, it would be appropriate to supply vitamin B12 and folate if there is deficiency in these vitamins. As many studies showed that an elevated Hcy level is a risk factor for developing CAD (12)(13)(14)(15), and Hcy is elevated by Iso treatment (11), evaluation of blood Hcy in patients on Iso therapy could be recommended.…”

Effect of Nitrous Oxide Exposure During Surgery on the Homocysteine Concentrations of Children

“…In populations consuming grains and flours fortified with folic acid, cobalamin deficiency has become the predominant vitamin-related cause of high homocysteine concentrations (75,76). Vitamin B6 supplementation showed a less dramatic effect on homocysteine concentrations in meta-analyses and clinical trials when compared to folic acid and cobalamin supplementation (77)(78)(79), however CBS deficient subjects respond to pyridoxine treatment with a marked decrease in total homocysteine concentrations (80). The two active forms of vitamin B6…”

Treatment of Alzheimer’s Disease with a Cholinesterase Inhibitor Combined with Antioxidants

“…Supplementation with vitamins B 6 , B 9 and B 12 or even B 6 alone has been found to reduce HCy levels [25][26][27] . Some clinical trials have shown that cardiovascular mortality is not affected by the use of the vitamin B group despite the decrease in HCy levels [28,29] .…”