Hormone replacement therapy with dydrogesterone and 17 beta-oestradiol: Effects on serum lipoproteins and glucose tolerance during 24 month follow up

Objective To assess serum lipid and lipoprotein concentrations and oral glucose tolerance in postmenopausal women treated with 17 beta-oestradiol (2 mg/day) and cyclical dydrogesterone (10 mg/day for 14 days per 28 day cycle). Design A 24 month prospective study of 29 women acting as their own controls. On-treatment samples were taken during the combined (oestrogen-progestogen) phase of therapy. Setting Metabolic research unit in London. Population Postmenopausal women with no previous exposure to hormone replacement therapy attending a menopause clinic in a London hospital. Methods Fasting serum sampling and oral glucose tolerance testing. Main outcome measures Serum lipids and lipoprotein concentrations and plasma glucose, insulin and C-peptide responses to an oral glucose load. Results Restricting the analysis to the 17 women who completed the study, no effect was seen on serum triglyceride concentrations. There was a mean fall of 5.9% (95% CI 1.2 to -13.0) in concentrations of serum total cholesterol, reflecting the balance of a 10.7% fall (95% CI 4.3 to -25.8) in low density lipoprotein cholesterol concentrations and a 16.3% increase (95% CI 7.3 to -25.3) in those of high density lipoproteins. Fasting glucose concentrations and glucose tolerance test responses were unchanged. Fasting insulin concentrations fell substantially (-41.6%, 95% CI -23.4 to -59.8) with falls also being seen in insulin responses to glucose. Fasting C-peptide concentrations increased by 36.2% (95% CI 9.17 to 63.3), with no consistent effect on C-peptide responses to glucose. Conclusions Dydrogesterone did not appear to oppose the potentially beneficial effects of oestradiol on insulin or either low or high density lipoproteins, making the combination with 17 beta-oestradiol a potentially useful option for postmenopausal women particularly those at risk of cardiovascular disease or diabetes mellitus.