Menopausal estrogen use, high density lipoprotein cholesterol subfractions and liver function

Forty-eight menopausal women taking exogenous estrogen were compared with 246 postmenopausal women not on estrogen. The estrogen users had significantly higher total high density lipoprotein (HDL) (76.0 vs 61.4 mg/dl) and HDL2 (36.7 vs 23.0 mg/dl) cholesterol than the controls. There was a similar concentration of HDL3 cholesterol for the two groups (39.2 for the estrogen users and 38.4 for the controls). A dose-response was evident between the amount of daily estrogen and HDL-total and HDL2 cholesterol. The significant differences between the two groups remained after adjusting for body composition, alcohol intake, cigarette smoking and physical activity. There was a significant difference between the two groups in liver function as measured by the liver enzymes, SGOT, SGPT, with liver enzyme concentrations lower in the estrogen users. The results indicate that the increase in the total HDL cholesterol as a result of menopausal estrogen is primarily the result of increased HDL2. The increase could not be explained by alterations in hepatic microsomal activity as measured by liver enzymes since estrogen users had lower concentrations of liver enzymes than non-estrogen users.