Long-term improvement in homocysteine levels and arterial endothelial function after 1-year folic acid supplementation

• Published in: The American journal of medicine Vol. 112; no. 7; pp. 535 - 539
• Main Authors: Woo, Kam S, Chook, Ping, Chan, Lindy L.T, Cheung, Alice S.P, Fung, Wing H, Qiao, M.u, Lolin, Yvette I, Thomas, G.N, Sanderson, John E, Metreweli, Con, Celermajer, David S
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.05.2002; Elsevier; Elsevier Sequoia S.A
• Subjects: Adult; Aged; Amino acids; Arteriosclerosis - prevention & control; Atherosclerosis (general aspects, experimental research); Biological and medical sciences; Blood and lymphatic vessels; Cardiology. Vascular system; Cardiovascular disease; Endothelial function; Endothelium, Vascular - diagnostic imaging; Endothelium, Vascular - drug effects; Female; Folic acid; Folic Acid - blood; Folic Acid - therapeutic use; Homocysteine; Humans; Hyperhomocysteinemia - drug therapy; Linear Models; Male; Medical sciences; Middle Aged; Multivariate Analysis; Ultrasonography; Vasodilation - drug effects; Vitamin B; Homocysteine; Folic acid; Endothelial function; Human; Thiol; Cardiovascular disease; Long term; Artery; Endothelium; Vascular disease; Sulfur containing aminoacid; Prevention; Homocystein; Atherosclerosis; Influence; Supplementation
• ISSN: 0002-9343; 1555-7162
• DOI: 10.1016/S0002-9343(02)01075-6

Hyperhomocysteinemia, a risk factor for atherosclerosis, is associated with endothelial dysfunction that can be improved with short-term folic acid supplementation. The current study aimed to assess whether folic acid supplementation could produce longer-term improvements in homocysteine levels and arterial endothelial function. Twenty-nine healthy adults with hyperhomocysteinemia were selected from 89 volunteers enrolled in a community-based atherosclerosis screening project. All subjects were given folic acid (10 mg/d) for 1 year. Fasting plasma homocysteine levels were measured by high-performance liquid chromatography. Arterial endothelial function was measured as flow-mediated dilation of the brachial artery using high-resolution B-mode ultrasound. Folic acid supplementation for 1 year was associated with a significant increase in mean (±SD) plasma folate levels (24 ± 5 nmol/L to 40 ± 5 nmol/L; P <0.001) and a significant decline in homocysteine levels (9.0 ± 1.7 μmol/L to 7.9 ± 2.0 μmol/L; P <0.001). Flow-mediated dilation also improved significantly, from 7.4% ± 2.0% to 8.9% ± 1.5% ( P <0.0001), but there was no change in nitroglycerin-induced (endothelium-independent) responses. These results demonstrate that long-term folic acid improves arterial endothelial function and has potential implications for the prevention of atherosclerosis in adults with hyperhomocysteinemia.