Impaired forearm blood flow and vasodilator reserve in healthy postmenopausal women

Background The natural process of cessation of ovarian estrogen production is associated with an increasing incidence of cardiovascular disease. Objective We aimed to determine whether postmenopausal women had menopause- associated vasomotor disturbances develop. Methods We studied the vascular forearm function using strain-gauge venous occlusion plethysmography in 12 healthy postmenopausal women (mean age +/- SD, 47 +/- 3 years; time-lapse from menopause >1 year). Twelve premenopausa l subjects marched for age and biophysical characteristics were used as a c ontrol group, Results No differences were observed in heart rate or mean blood pressure b etween the 2 groups of women. Forearm blood flow at supine resting was lowe r in postmenopausal than in premenopausal women (2.4 +/- 0.8 vs 3.1 +/- 0.5 mL/100 mL/min; P < .05), local vascular resistance was higher in postmenop ausal than in premenopausal women (43.5 +/- 17.5 vs 31.1 +/- 4.3 mm Hg/mL/1 00 mL/min; P < .05). Moreover, peak Forearm flow in response to forearm isc hemia was 20.8 +/- 7.9 mL/100 mL/min in postmenopausal women and 26.6 +/- 9 .7 mL/100 mL/min in premenopausal women (P < .01), Plasma concentration of noradrenaline in the supine position was significantly higher in postmenopa usal than in premenopausal women (286 +/- 22 pg/mL vs 195 +/- 33 pg/mL; P < .01). Finally, a significant positive relation was revealed in postmenopau sal women between the amount of vasodilator reserve (D Flow) in local perip heral circulation and levels of circulating estradiol-17 beta. Conclusions Abnormalities observed in forearm blood flow and vasodilator ca pacity in postmenopausal women may be attributed to a critical loss of the vasodilating property of physiologic estrogen. Our data support the possibi lity that reduction in dilator capacity of the vasculature may contribute t o the increase of cardiovascular disease after menopause.