Homocysteine is the only plasma thiol associated with carotid artery remodeling

Several authors have reported that moderate hyperhomocysteinemia is related to asymptomatic carotid arterial wall remodeling, but few data are available on other thiol compounds with potential vascular toxicity. We, therefore, investigated the relationships between major plasma thiol compounds (homocysteine, cysteine and glutathione) and the structural phenotype of the common carotid artery in a cohort of 123 subjects with no evidence of cardiovascular disease. Fasting levels of thiol compounds were measured by high-performance liquid chromatography, and arterial geometry was evaluated using high-resolution echotracking devices. In univariate regression analysis, plasma homocysteine and plasma cysteine concentrations were positively associated with carotid artery internal diameter (P=0.0001 and 0.002, respectively) and intima media thickness (P=0.003 and 0.004), but the plasma glutathione concentration was not. In multivariate analysis, plasma homocysteine was independently and positively associated with carotid artery internal diameter (P<0.005) and intima media thickness (P<0.05), but plasma cysteine was not. These data suggest that homocysteine is the only plasma thiol compound that may be considered as a risk factor for preclinical cardiovascular disease.