Time since menopause does not affect plasma viscosity, plasma thromboxane levels and Doppler findings

Objectives. To evaluate whether the use of transdermal hormone replacement therapy (HRT), in women within 5 years of menopause compared with women who were postmenopausal for > 5 years, would significantly influence thromboxane B2 levels, plasma viscosity and Doppler flow parameters at the level of the uterine, internal carotid, ophthalmic and bladder wall arteries. Methods. Thirty-five normal-weight (body mass index > 19 and <25 kg/m²) postmenopausal women (age 54.6 ± 3.9 years, mean ± standard deviation) participated in the study and were divided into two groups (Group I: w = 19, time since menopause <5 years; and Group II: n = 16, time since menopause > 5 years). Patients were treated with a continuous estradiol transdermal supplementation and 12-day courses of medroxyprogesterone acetate every 2 months. They were studied at baseline and after 6 months (in the estrogen-only phase of the cycle). Results. Results showed a beneficial effect of hormone substitution after 6 months of therapy. Baseline plasma viscosity was similar in both groups, and decreased significantly after therapy in both Group I (-17.5%) and Group II (-15.6%). Plasma levels of thromboxane B₂ were similar at baseline and diminished equally in Group I and Group II (-85.6% and -85.2%, respectively) after treatment. Doppler assessment of the pulsatility index at the level of uterine, internal carotid, ophthalmic and bladder wall arteries showed no differences between groups at baseline and revealed a significant reduction of vascular impedance at the end of the treatment in both groups. Conclusions. Time since menopause does not affect the ootential hemodvnamic benefits of HRT in normal-weight women.