vitamin-b-12 and Angina--Unstable

High plasma homocysteine (Hcy) levels are known to be associated with coronary artery disease, but the precise level associated with an increased risk is yet controversial. Whether the beneficial effects of folic acid on arterial endothelial function persist over longer periods is not known. This study was carried out to assess whether folic acid supplementation could produce improvements in Hcy levels and arterial endothelial function in the patients with unstable angina (UA) and hyperhomocysteinaemia.. The plasma Hcy levels of 52 cases with UA and 30 control subjects were measured by using high-performance liquid chromatography (HPLC) with fluorescence detection, plasma folic acid and vitamin B(12) levels were also measured. The patients with hyperhomocysteinaemia were treated with 5 mg of folic acid for 8 wk, and then rechecked the plasma levels of Hcy, folic acid and vitamin B(12) at the end of 4(th) and 8(th) wk. Arterial endothelial function was measured as flow-mediated dilation of the brachial artery using high-resolution B-mode ultrasound in 22 cases with UA and hyperhomocysteinaemia before and after folic acid treatment.. The plasma Hcy level was significant higher in the patients with UA than in the controls (19.2 +/- 4.9 vs 10.7 +/- 5.3 micromol/l, P<0.01). The plasma levels of folic acid and vitamin B12 were significant lower in the patients with UA than in the controls. There were 22(42.3%) patients with hyperhomocysteinaemia in UA group. After 4 and 8 wk of administration of folic acid, the Hcy level reduced by 20.3 and 55.3 per cent in the UA patients with hyperhomocysteinaemia, respectively. Flow-mediated dilation also improved significantly, from 6.4 +/- 1.9 to 9.0 +/- 1.2 per cent (P<0.05) after 8 wk treatment with folic acid.. Plasma Hcy level was elevated in patients with UA. Folic acid can reduce the plasma Hcy levels and improve arterial endothelial function in the UA patients with hyperhomocysteinaemia.

Topics: Acute Coronary Syndrome; Adult; Aged; Angina, Unstable; Endothelium, Vascular; Female; Folic Acid; Homocysteine; Humans; Hyperhomocysteinemia; Male; Middle Aged; Risk Factors; Vasodilation; Vitamin B 12; Vitamin B Complex

Hyperhomocysteinemia is currently regarded as an independent and modifiable risk factor for ischemic vascular diseases and thrombosis. We measured fasting plasma total homocysteine levels by HPLC with fluorescence detection in 30 patients presenting with acute coronary syndromes and 30 age and sex-matched control subjects. Demographic data, classical risk factors (systolic blood pressure, diabetes mellitus, smoking, ethanol intake, family history of ischaemic heart disease) and life-style habits were recorded. Lipid fractions including total cholesterol, triglycerides, HDL-cholesterol, total cholesterol/HDL-cholesterol ratio, serum creatinine, LDL-cholesterol and vitamins involved in the metabolism of homocysteine, folic acid and vitamin B12 were also assessed. Total fasting homocysteine concentrations were significantly higher in the patient group (12.2 +/- 1.01 micromol/l) than in the control subjects (7.05 +/- 0.36 micromol/l; p < 0.0001). Homocysteine correlated positively with age (r = 0.617; p < 0.01) and serum creatinine (r = 0.457; p < 0.01) in the patient group. Hyperhomocysteinemia was not associated with vitamin B12 or folate deficiency states. Vitamin B12 concentration was 273 +/- 16.4 ng/l in the control group and 284.3 +/- 32.2 ng/l in the patient group (p = NS). Serum folate concentration also was not significantly different between controls and patients; 7.57 +/- 0.58 microg/l and 8.05 +/- 0.72 microg/l, respectively. Since no significant difference was observed in the lipid parameters between patients and controls, the hyperhomocysteinemia in the patient group supports the view that homocysteine is an independent risk factor for cardiovascular diseases. Our results strongly suggest that elevated homocysteine levels are among the interacting factors in the complex, multifactorial pathophysiology of ischemic heart disease.

Topics: Adult; Aged; Angina, Unstable; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Creatinine; Female; Folic Acid; Homocysteine; Humans; Male; Middle Aged; Myocardial Infarction; Risk Factors; Vitamin B 12