Effects of oral estradiol and levonorgestrel on cardiovascular risk markers in postmenopausal women

Abstract

This study aimed at investigating changes in postmenopausal women's cardiovascular risk markers induced by hormone therapy regimens of low (1.0 mg) or ultra-low (0.5 mg) doses of micronized estradiol (mE(2)) and levonorgestrel (LNG). Three randomized placebo-controlled trials were reanalyzed with regard to changes in cardiovascular risk markers, such as serum lipids, lipoproteins, and coagulation parameters. Trial 1 (n = 210) was an 8-week study comparing the effects of 1.0 or 0.5 mg of unopposed mE(2) on menopausal symptoms. Trial 2 (n = 194) was a 24-week study comparing the effects of 1.0 mg of mE(2) combined with 10, 20, or 40 μg of LNG on endometrial safety. Trial 3 (n = 195) was a 52-week study comparing the effects of 1.0 or 0.5 mg mE(2) + 40 μg LNG on bone metabolism. 1.0 mg of unopposed mE(2) reduced low-density lipoprotein cholesterol (LDL-C) after as little as 8 weeks. 1.0 mg mE(2) for 24 weeks lowered the serum levels of total cholesterol (TC) and LDL-C, whereas the addition of LNG caused decreases in the levels of high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG) in a dose-dependent fashion. 1.0 or 0.5 mg mE(2) + 40 μg LNG for 52 weeks also lowered the levels of TC, HDL-C, LDL-C, and TG. Both regimens slightly lowered antithrombin and Protein C activities within normal limits. Hormone therapy using 1.0 or 0.5 mg of mE(2) and LNG lowers the serum levels of TC, HDL-C, LDL-C, and TG without significantly affecting coagulation/fibrinolysis parameters.