8 determination of plasma homocysteine.

A number of epidemiological and clinical studies have linked elevated plasma homocysteine (Hcy) to atherosclerotic vascular disease affecting coronary, carotid, and peripheral vessels. Plasma Hcy can be considered a marker of methionine metabolic efficiency, mainly affected by dietary intake of vitamins, especially folate, vitamin B(6), and B(12), as well as by genetic mutations of key metabolic enzymes and renal elimination.