Postmenopausal hormone replacement therapy and cerebrovascular diseases

Epidemiologic and animal studies have provided evidence that hormone replac ement therapy can reduce the risk of stroke. Doppler ultrasound measurement s of blood flow show a positive effect of estrogens on the cardiovascular s ystem, which is only slightly modified by progestins. Ultrasound measuremen ts of intima-media thickness showed a positive influence of longterm hormon e replacement therapy on the cerebral vasculature. The intima-media thickne ss, a marker of complex atherosclerosis decreases with hormone replacement therapy. The number of atherosclerotic plaques in extracranial cerebral ves sels is significantly lower in patients receiving hormone replacement than in controls. One study suggested that estrogen replacement can lead to regr ession of atherosclerotic plaques. Hormone replacement therapy may reduce t he risk for developing and progression of cerebrovascular atherosclerosis. In patients with a history of stroke the possible benefits of hormone repla cement have to be weighed against risks, particularly in patients with othe r risk factors. We review our results and the literature.