Sex hormones and lipoproteins in men

To clarify the conflicting evidence of an association between endogenous sex hormones and lipoprotein metabolism in men, we examined the relationship between sex hormone levels, total cholesterol, and high-density lipoprotein cholesterol (HDL-C), taking into account the coronary artery disease (CAD) status of the subjects.

Sex hormone levels, total cholesterol, and HDL-C were measured in 67 men with CAD from among 191 consecutive male patients between the ages of 25 and 75 undergoing coronary angiography, in 26 men without angiographic evidence of CAD, and in 55 men who were clinically free of CAD.

There was a consistently positive correlation between total estradiol or calculated free estradiol and both total cholesterol and HDL-C, which persisted after adjustment for potential confounders. Total cholesterol was associated with total testosterone after controlling for age, adiposity, and the presence or absence of CAD, but not with calculated free testosterone. No association was noted between total testosterone or calculated free testosterone and HDL-C. A significant interaction was observed between estradiol and testosterone with respect to total cholesterol.

This study demonstrates an association between sex hormone levels and lipoprotein metabolism, specifically between estradiol levels and both total cholesterol and HDL-C. Unlike most previous investigators, we were able both to control for the CAD status of our subjects and to consider unbound, biologically active hormone levels. In addition, we documented a complex interaction between endogenous testosterone and estradiol in relation to lipoprotein levels; this association should be considered in future studies.