Effects of estradiol alone or in combination with cyproterone acetate on carotid artery pulsatility index in postmenopausal women

OBJECTIVES: The incidence of cardiovascular disease (CVD) increases dramatically with the loss of ovarian function. Observational studies indicate that the risk of CVD may be reduced by up to 50% in postmenopausal women who take estrogen replacement therapy. Estrogen therapy reduces internal carotid artery pulsatility index (PI). The improvement in carotid PI following HRT has been proposed as a marker of the cardioprotective effect of estrogen therapy. Cyclical progesterone addition to ERT partially antagonizes the reduction on the carotid artery PI. As progesterone, androgens has been shown to decreases arterial vasodilatation and carotid PI. To our knowledge no information is available regarding the effect of CPA addition on the carotid artery PI in women taking estrogen replacement therapy. METHODS: We recruited a total of 30 women in postmenopause for at least 12 months and were in good health. Fifteen women were postmenopausal following surgical bilateral oophorectomy for benign condition. Fifteen postmenopausal women received estradiol valerate for 21 days and CPA (1 mg) for 10 days for 3 months (Group E/CPA). Ovarectomized women (n=15) received estradiol hemihydrate (2 mg) for 3 months (Group E). The main factor investigated was PI, an indicator of impedence to blood flow down stream. Doppler US were performed before the start and at the end of the therapy. RESULTS: The mean reductions respect to basal values were 11.5% in women treated with E and 10.8% in women treated with E/CPA. No significant difference was found between treatment values. CONCLUSIONS: The results of the present study demonstrate that cyproterone acetate addition to E do non-antagonize the effect of estrogen on carotid artery PI. The present study demonstrate that both estradiol hemihydrate and estradiol valerate plus cyproterone acetate lead to similar improvement in carotid artery; through this mechanism both treatments could potentially reduce the incidence of cerebrovascular disease in postmenopausal women