LOW-DOSE PROGESTERONE THERAPY IN ESTROGENIZED POSTMENOPAUSAL WOMEN - EFFECTS ON PLASMA-LIPIDS, LIPOPROTEINS AND LIVER-FUNCTION PARAMETERS

Background - Cardiovascular disease among older women is a major health problem and is the leading cause of death in this group in developed countries. The risk is reduced in oestrogen users secondary to favourable lipid changes, but the beneficial effect of oestrogen may be counteracted when concomitant progestogens are administered. Objective - To study the effects of a novel hormone replacement therapy regimen on liver enzymes, lipids and lipoproteins in postmenopausal women. Design - Prospective open, non-comparative trial for 12 months. Methods - 40 healthy postmenopausal women, (mean age +/- S.D.). 53.5 +/- 3 years received 0.625 mg of conjugated equine oestrogen daily and 100 mg of micronised oral progesterone (P) for the first 23 days every calendar month for 12 months without interruption. Main outcome measure - Gonadotrophins, liver function parameters and lipoproteins were measured before treatment and at the 6th, 9th and 12th months of treatment. Results - Compliance with treatment was confirmed by a 33% decrease in mean serum level of follicle stimulating hormone at the end of 1 year of treatment. In the same period, the mean serum cholesterol, LDL and LDL/HDL ratio decreased by 6%, 16% and 23% of the base line levels, respectively. The percentage changes in triglycerides and HDL from the basal levels were +32% (P < 0.001) and +15% (P < 0.05), respectively. Conclusion - These results indicate that near continuous administration of fixed low-dose of P has no adverse effects on the lipid milieu of postmenopausal women when combined with long-term continuous oestrogen replacement therapy provided women with borderline triglyceridaemia are excluded.