Metabolic effects of continuous estradiol-progestin therapy in postmenopausal women

Sixty postmenopausal women with climacteric complaints were randomly allocated to four treatment groups. Without interruption, each patient was given one tablet daily containing 2 mg 17 beta-estradiol along with either norethisterone acetate 1 mg and 0.5 mg or megestrol acetate 5 mg and 2.5 mg. Blood samples were obtained before treatment and then after 1, 4, and 12 months of treatment. Serum was analyzed for cholesterol and triglycerides in serum and for cholesterol in the ultracentrifugally separated lipoprotein fractions of very low-density lipoproteins, low-density lipoproteins, and high-density lipoproteins. Significant reductions of serum cholesterol were found in all treatment groups except for that given 2.5 mg megestrol acetate. After 1 and 4 months of treatment, low-density lipoprotein cholesterol decreased 7-22%, whereas high-density lipoprotein cholesterol was reduced by 2-16% in the four groups. No significant differences could be demonstrated among the groups in low-density lipoprotein cholesterol or high-density lipoprotein cholesterol during treatment, as assessed by analysis of variance. Thus, cholesterol metabolism was equally influenced by both progestin types. Accordingly, the clinical efficacy and acceptance would decide the preparation to be advocated for women in need of hormone replacement therapy.