Effect of hormone therapy on exercise capacity in early postmenopausal women.

OBJECTIVE To compare the exercise capacity of postmenopausal women with matched premenopausal controls, as well as postmenopausal women before and after 3 months of hormone therapy (HT). METHODS This study examined the response to strenuous isotonic exercise in 30 women with recently developed menopause (age, mean+/-standard deviation, 50.6+/-1.1 years) without cardiovascular risk factors or diseases. Thirty premenopausal subjects, matched one-to-one for age and biophysical characteristics, were the control group. Postmenopausal women underwent examination before (T(0)) and 3 months after (T(1)) HT (oral 0.625 mg conjugated estrogen and 2.5 mg medroxyprogesterone acetate/day) with high-resolution ultrasound determination of peripheral flow-mediated vasodilation and an integrative cardiopulmonary test. RESULTS Postmenopausal women showed an impairment of flow-mediated vasodilation (P<.001) in the radial artery and a worsening of physical performance, primarily exemplified by lower maximal workload (P<.01) and peak oxygen consumption (Vo(2)max, P<.001) compared with premenopausal women. After 3 months on HT, ergometabolic parameters and vasodilation reserve were at a level comparable to premenopausal women. Flow-mediated vasodilation measurements after 3 months on HT significantly correlated with those of peak oxygen consumption (r=0.77, P<.001) and the ratio between the increase in oxygen consumption and that in work rate (DeltaVo(2)/DeltaWR) (r=0.73, P<.001). CONCLUSION The peripheral circulation is the limiting system in postmenopausal women experiencing exercise intolerance, and there are benefits in introducing HT.