OBJECTIVE: To determine plasma homocysteine levels and the incidence of methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism in a group of subjects who underwent coronary angiography, in an attempt to establish a correlation between these parameters and the severity of coronary artery disease (CAD), as well as investigate the correlation between hyperhomocysteinemia and the presence of polymorphism. METHODS: Twenty subjects with no coronary atheromatosis (controls), fourteen subjects with mild/moderate atheromatosis, and twenty-nine subjects with severe atheromatosis were evaluated. RESULTS: Significant differences were observed in mean homocysteine levels between the control and the severe atheromatosis groups (p < 0.001). No significant differences were observed among the other groups. The severe atheromatosis group showed rates of 62.0% and 6.9% for the C677T MTHFR gene polymorphism, in heterozygous and homozygous subjects, respectively. However, there was no correlation between the presence of mutation and hyperhomocysteinemia. A positive correlation of 41.91% (p < 0.001) was found between hyperhomocysteinemia and CAD. CONCLUSION: The most important finding of this study was the association between hyperhomocysteinemia and coronary stenosis > 70%; yet, whether elevated plasma homocysteine worsens atherosclerosis or is a consequence remains to be established.
Homocysteine; methylenetetrahydrofolate reductase (MTHFR); coronary angiography
