Effects of transdermal and oral estrogen replacement on lipids and glucose metabolism in postmenopausal women with type 2 diabetes mellitus.

OBJECTIVE

To compare the effects of oral and transdermal estrogen replacement on lipid and glucose metabolism in postmenopausal women with diabetes mellitus type 2.

DESIGN AND METHODS

In an open, randomized, cross-over study, 21 diabetic postmenopausal women were treated with transdermal 17beta-estradiol 50 microg or oral conjugated equine estrogens (CEE) 0.625 mg daily, both associated with 300 mg/day of oral micronized progesterone for 12 days monthly during 6 months each. After a 12-h overnight fasting period, blood glucose, insulin, glycosylated hemoglobin (HbA1c) and lipoprotein profile were evaluated, at baseline and after 6 months of each schedule of hormone replacement therapy (HRT). Insulin sensitivity was determined by homeostasis model assessment (HOMA).

RESULTS

HRT had no negative influence on glucose metabolism. After 6 months of CEE treatment, there was a significant increase in high-density lipoprotein (HDL) cholesterol, but also in triglycerides, of 9.0% and 20.7%, respectively (p = 0.04). The levels of total cholesterol and low-density lipoprotein (LDL) cholesterol were unaffected. Transdermal estradiol did not affect the lipid profile.

CONCLUSIONS

Hormone replacement therapy with either oral or transdermal estrogen plus micronized progesterone has no harmful influence on glucose metabolism in type 2 diabetic postmenopausal women; whether the increase in HDL cholesterol, but also in triglyceride levels, makes oral CEE the better choice remains an open question.