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.