Effects of hormone replacement therapy on insulin resistance and platelet function tests

ABSTRACT

The aim of this study was to evaluate measures of insulin resistance and platelet function in postmenopausal women with oral or transdermal hormone replacement therapy [HRT]. Eighty women divided into four groups of 20 each were enrolled in the study. Group 1 postmenopausal hysterectomized women who received only transdermal estradiol [13.9 mg/12.5 cm2]; group 2 women with intact uterus who were treated with estrogen-progestin combination [HRT]; group 3 postmenopausal women who were treated with the selective estrogen receptor modulator tibolone, and group 4 women who were not taking any drugs for HRT were chosen as a control group [group 4]. In group 2, homeostasis model assessment of insulin resistance and fasting insulin levels were 2.90 +/- 0.37 and 9.3 +/- 3.0 micro U/ml, respectively, prior to administration of HRT. These levels were reduced to 1.91 +/- 0.41 [p = 0.001] and 7.1 +/- 2.7 micro U/ml [p = 0.002], respectively, after drug therapy. Mean levels of high-sensitivity C-reactive protein [hsCRP] were decreased with HRT only in group 2 [p = 0.002]. No changes for biochemical and hematological parameters were observed in the other groups. Platelet function tests showed no differences after HRT in any group. Estrogen-progestin combination HRT decreased measures of insulin resistance and hsCRP levels, but had no effect on platelet function tests in postmenopausal women