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

• Published in: European journal of clinical nutrition 2004-03, Vol.58 (3), p.481-487
• Main Authors: Lee, B.J, Huang, M.C, Chung, L.J, Cheng, C.H, Lin, K.L, Su, K.H, Huang, Y.C
• Format: Article
• Language: English
• Subjects: Acids; Activity coefficients; Adult; Aged; Aged, 80 and over; Alanine; Biological and medical sciences; Cardiology; Cardiology. Vascular system; Cardiovascular disease; Catheterization; Clinical Nutrition; Coronary artery; Coronary artery disease; Coronary Artery Disease - blood; Coronary heart disease; Coronary vessels; Cyanocobalamin; Dietary supplements; Dose-Response Relationship, Drug; Epidemiology; Erythrocytes; Fasting; Female; Folic acid; Folic Acid - administration & dosage; Folic Acid - blood; Food intake; Heart; Heart diseases; Homocysteine; Homocysteine - blood; Humans; Internal Medicine; Male; Medical sciences; Medicine; Medicine & Public Health; Mental Recall; Metabolic Diseases; Middle Aged; Nutrients; original-communication; Patients; Placebos; Plasma; Public Health; Pyridoxine; Single-Blind Method; Stenosis; Treatment Outcome; Vein & artery diseases; Vitamin B; Vitamin B 12 - administration & dosage; Vitamin B 12 - blood; Vitamin B 6 - administration & dosage; Vitamin B 6 - blood; Vitamin B12; Vitamin B6
• ISSN: 0954-3007; 1476-5640
• DOI: 10.1038/sj.ejcn.1601834

Objective: To investigate whether vitamin B6 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=8), 5 mg vitamin B6 (n=8), 10 mg vitamin B6 (n=8), 50 mg vitamin B6 (n=9), or 5 mg folic acid combined with 0.25 mg vitamin B12 (n=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 B6 status was assessed by direct measures (plasma pyridoxal 5'-phosphate) and indirect measures (erythrocyte alanine and aspartate aminotransaminase activity coefficient). Fasting plasma homocysteine, serum folic acid, and vitamin B12 were measured. Results: Fasting plasma homocysteine concentration did not respond to high or low doses of vitamin B6 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 B12 supplementation (P=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 B6 supplemented groups, respectively; whereas folic acid combined with vitamin B12 supplementation significantly reduced fasting plasma homocysteine concentration by 32% (P