Hyperhomocysteinemia Emerged Recently as a Vascular Risk Marker, both in Arterial and Venous Systems: Why Is This Marker so Important?

Hyperhomocysteinemia is the consequence of impaired methionin metabolism, usually due to a deficiency in cystathionine b-synthase. It is associated with premature cerebral, peripheral and coronary vascular disease for several years but the strength of this association and its independence of other risk factors was unknown until Clarke et al. [1991] reported a study of 123 patients whose vascular disease had been diagnosed before they were 55 years of age. Hyperhomocysteinemia was detected in that study in 42% (16/3 8) of patients with cerebrovascular disease, 28% (7/25) of patients with peripheral arterial disease and 30% (18/60) of those with coronary artery disease. None of the 27 normal subjects had abnormal homocysteine plasma levels. After adjustment for the effects of conventional risk factors, the odds ratio for cerebrovascular disease was 40.3 (95%i confidence interval 4.0-oo) when hyperhomocysteinemia was detected in this population with premature vascular disease. For all ...  more