Homocysteine is a thiol-containing amino acid derived from methionine metabolism that can be degraded through two different enzymatic pathways.

Clinical Implications:

Progressively elevated blood levels of homocysteine lead to increased oxidative stress, endothelial dysfunction and vascular injury, and enhanced thrombogenicity. Elevated homocysteine levels are associated with a two to three-fold increase in cardiovascular disease risk. Values in excess of 14 µmol/ml are considered elevated.

Treatment considerations:

• Diet high in green leafy vegetables
• Identify and treat underlying abnormality such as renal insufficiency/pernicious anemia
• As an associated combined risk factor, aggressively treat all other abnormal tests
• While traditional treatment has been folic acid, B-6, and B-12 vitamins; initiating treatment of elevated homocysteine continues to be controversial.

For more information and detailed references, please refer to our Clinical Implications Reference Manual.