[Homocysteinemia: role in vascular disease]

HEREDITARY DISEASE: Hereditary anomalies of homocysteine metabolism are quite uncommon and manifest by very high homocysteine levels (100 mumol/l) and associated homocysteinuria. The risk of premature cardiovascular disease is high. Clinical, biological and epidemiological data accumulated since the 70 s have demonstrated that a moderately elevated serum homocysteine level favors the development of atherothrombosis. PROVEN RISK: The risk of coronary or cerebral events is 1.5 to 3-fold higher for fasting homocysteine levels above 15 mumol/l. These data show that moderately elevated homocysteine level is a powerful cardiovascular risk factor. Further information is however needed to ascertain its frequency in the population and determine whether it is a truly independent risk factor.Most cases of moderately elevated homocysteine can probably be explained by gene-environment interactions. Homocysteine levels can be lowered by oral administration of vitamin cofactors implicated in homocystein metabolisms: folic acid, vitamin B6, vitamin B12.