The effect of hormone replacement therapy alone and in combination with simvastatin on plasma lipids of hypercholesterolemic postmenopausal women with coronary artery disease.

OBJECTIVES This study sought to compare hormone replacement therapy (HRT), simvastatin and their combination in the management of hypercholesterolemia in postmenopausal women with coronary artery disease (CAD). BACKGROUND Lipid-lowering therapy reduces mortality in hypercholesterolemic women with CAD. In postmenopausal women HRT seems to increase survival, particularly those with ischemic heart disease, and this is partly due to changes in lipid levels. METHODS We studied 16 postmenopausal women with CAD and fasting total cholesterol <200 mg/dl and low-density lipoprotein (LDL) cholesterol <130 mg/dl. We compared HRT (0.625 mg of conjugated estrogen and 2.5 mg of medroxyprogesterone acetate daily) with simvastatin (20 mg daily) and their combination in a randomized, crossover, placebo-controlled study. Each treatment period was 8 weeks long with a 4-week washout interval between treatments. RESULTS Simvastatin, HRT and their combination significantly reduced total and LDL cholesterol by 35%, 13%, and 33% and 45%, 20%, and 46%, respectively, compared to placebo (p < 0.001). However, simvastatin and the combination was superior to HRT (p < 0.001), and none of our patients had total cholesterol <180 mg/dl and LDL cholesterol <100 mg/dl on HRT alone. High-density lipoprotein cholesterol was not significantly affected by any of the active treatments, and triglycerides were lower during simvastatin therapy compared to placebo (p < 0.01). Apolipoprotein B was significantly reduced by simvastatin, alone and combined with HRT, by 39% and 35%, respectively, compared to placebo (p < 0.001). Alone and in combination with simvastatin, HRT significantly increased apolipoprotein A-I by 11% and 12%, respectively, compared to placebo (p < 0.05) and decreased lipoprotein (a) by 23% and 33%, respectively, compared to placebo (p < 0.05), whereas simvastatin had no significant effect on either of these parameters. CONCLUSIONS In hypercholesterolemic postmenopausal women with CAD, HRT exerts beneficial effects on plasma lipids but the levels currently recommended for secondary prevention are not achieved. Hormone replacement therapy combined with simvastatin is well tolerated and extremely effective, as the two therapies seem to be additive.