Effect of oestrogen replacement therapy on serum lipid profile

Oestrogen deficiency in postmenopausal women alters the lipid metabolism unfavourably.

To evaluate the effects of oral and transdermal oestrogen replacement therapy (ORT) on serum lipid profile.

Ninety hysterectomised and oophorectomised women were randomised into three equal groups (no hormones; oral conjugated equine oestrogen, 0.625 mg/day; transdermal oestradiol patches, 50 microg/day). Serum concentrations of total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol and triglycerides were determined at the baseline and after 3 and 6 months of therapy. Student's t-test was used for statistical evaluation.

Most of the hysterectomised women had abnormal serum lipid profile, especially HDL cholesterol levels (less than 40 mg/dL in 87%). A significant decline in the levels of serum cholesterol (total) as well as LDL and a significant increase in HDL cholesterol levels were observed following ORT by both modes, the response being comparatively rapid with oral route. After 3 and 6 months, the number of cases with HDL cholesterol levels above 40 mg/dL increased from initial 13 to 63% and 87% (oral) and 30 and 60% (transdermal), respectively. Serum triglyceride levels declined significantly with transdermal therapy but increased with oral ORT.

Oestrogen replacement therapy either via oral or transdermal route has a beneficial effect on serum lipid profile of menopausal women. Whereas the oral route is more effective in increasing HDL cholesterol levels, the transdermal route is better for reducing the serum triglyceride level; hence, the latter should be the route of choice in women with high serum triglyceride levels.