Substitution of transdermal estradiol during oral estrogen-progestin therapy in postmenopausal women: effects on hypertriglyceridemia.

Objective: We investigated effects of changing from oral estrogen to transdermal estradiol on the lipid and lipoprotein profile of postmenopausal women who developed hypertriglyceridemia (serum concentrations exceeding 150 mg/dL) during estrogen-progestin therapy.

Methods: Sixty-one postmenopausal Japanese women receiving 0.625 mg of conjugated equine estrogen plus 2.5 mg of medroxyprogesterone acetate daily for 12 months had developed serum triglyceride concentrations exceeding 150 mg/dL after 12 months of treatment. Thirty-six of them, chosen randomly for study, were assigned at random to either a group that continued this oral regimen or another that changed to transdermal estradiol while continuing 2.5 mg of oral medroxyprogesterone acetate for the next 3 months (n = 18 for each). Blood lipids were compared between groups.

Results: Serum concentrations of triglyceride and very-low-density lipoprotein triglyceride decreased significantly after changing to transdermal estradiol (triglyceride, from 226.0 +/- 43.9 to 110.5 +/- 44.1 mg/dL, P < 0.01). No changes were seen in concentrations of low-density lipoprotein cholesterol or high-density lipoprotein cholesterol.

Conclusions: Changing to transdermal estradiol may improve triglyceride metabolism in women who developed hypertriglyceridemia during oral estrogen-progestin therapy, with minimal effect on cholesterol profiles.