Several polymorphisms of the renin-angiotensin-aldosterone system have been found to have pleiotropic effects on cardiovascular diseases. Polymorphism of the aldosterone synthase gene (CYP11B2), which may influence plasma aldosterone levels, has been reported to cause systemic hypertension, influence the left ventricular diameter and mass, and decrease baroreflex sensitivity of the cardiovascular system. Through these mechanisms, it is thought to increase the risk of myocardial infarction (MI). Our study was designed to elucidate whether polymorphism of CYP11B2 increased the risk of MI.

We analyzed the genotypes of CYP11B2 and the classic risk factors of MI in 188 MI patients and 320 control subjects without history of MI.

There was no significant difference in the distribution of genotypes between the patient and control groups. Adjusting for the classical risk factors, multiple logistic regression analysis showed no significant effect of CYP11B2 gene polymorphism on the development of MI. However, the presence of the -344C allele is associated with a markedly increased MI risk conferred by classic risk factors including hypertension, smoking, and male sex. In particular, hypertension was not a significant risk factor as compared with non-hypertensive patients in subjects without -344C, but the relative risk was increased to 2.40 (95% CI:1.05-5.51, p<0.05) with - 344C. The relative risks of smoking and male sex were also increased with the presence of the - 344C allele.

CYP11B2 polymorphism is not an independent risk factor of MI, although hypertension, smoking, and male sex are more potent risk factors for MI in Koreans who possess the - 344C allele.