Three-year study of estrogen alone versus combined with progestin in postmenopausal women with or without hypercholesterolemia

Abstract

This study compares the effects of long-term hormone replacement therapy on the lipid profile of postmenopausal women with or without hypercholesterolemia, with a comparison of 2 different regimens over a 3-year period. A total of 209 women were enrolled in this prospective, nonrandomized trial. They were classified into 2 groups according to baseline serum levels of total cholesterol and low-density lipoprotein (LDL) cholesterol. The hypercholesterolemic group consisted of 83 subjects with a total cholesterol level of 220 mg/dL or higher and LDL cholesterol 140 mg/dL or higher. The normocholesterolemic group consisted of 126 subjects with normal total and LDL cholesterol levels. Therapy was assigned as follows: 44 subjects in the hypercholesterolemic group and 67 in the normal cholesterol group with a total hysterectomy received conjugated equine estrogen (CEE) 0.625 mg/d, while 39 subjects in the hypercholesterolemic group and 59 in the normal cholesterol group with a physiological menopause received CEE 0.625 mg/d plus medroxyprogesterone acetate 2.5 mg/d. Fasting blood samples were monitored periodically for 3 years. Nine women withdrew from the study. Hormone replacement therapy had a more favorable effect in the hypercholesterolemic group versus the normal cholesterol group by decreasing total and LDL cholesterol, 7.0% and 16.6%, versus the normal cholesterol group, 0.8% and 3.9%. Serum levels of high-density lipoprotein (HDL) cholesterol were increased in both groups (hypercholesterolemic, 14.4%; normal cholesterol group, 26.5%), with the increase being larger in the normal cholesterol group. These changes were similar with both treatments and were maintained over 3 years. Serum levels of triglyceride were also increased in both groups, with the increase being statistically significant only in the group with normal cholesterol levels at baseline. There were no consistently reported side effects of therapy. The effects of postmenopausal hormone replacement therapy, estrogen with or without progestin, on the lipid profile appear to be related to the subject's baseline lipid values. Thus, such therapy may have a more favorable effect on LDL cholesterol in postmenopausal women with hypercholesterolemia, with the beneficial effect being maintained over 3 years.