Paola Pifarotti

Effects of Hormone Replacement Therapy on Lipids and Lipoproteins in Dyslipidemic Postmenopausal Women: A Comparison Between Transdermal and Oral Estrogen

The physiologic effects of combination hormone replacement therapy are less well established than the effects of estrogen alone. Recently the Postmenopausal Estrogen/ Progestin Interventions (PEPI) Trial [1] offered the most definitive conclusion that estrogen alone or in combination with a progestin decreased low density lipoprotein (LDL) cholesterol and increased high density lipoprotein (HDL) cholesterol. The higher levels of triglycerides, although potentially detrimental, seem to be related to an increased production of large very low density lipoproteins (VLDL), which are less atherogenic than small VLDL. Reports of the metabolic effect of transdermal estrogen are conflicting. Overall, it seems that transdermal estradiol is less effective than oral estrogen on LDL and HDL cholesterol, whereas a fall in triglycerides has been reported [2]. Recently, the National Cholesterol Education Program Adult Treatment Panel II Guidelines suggested hormone replacement therapy an alternative to standard treatments for dyslipidemic postmenopausal women [3].