Hormone replacement therapy and stroke: are the results surprising?
Despite major progress in treatment and prevention, stroke remains the leading cause of disability and the third leading cause of death, surpassed only by heart disease and cancer, in the United States.1 An estimated 500 000 to 600 000 first and 100 000 recurrent strokes occur each year, and ≈160 000 of these are fatal.2 Among stroke survivors, the burden of long-term disability is great. In the Framingham Heart Study, 71% had impairments that affected their ability to work in their previous capacity and 31% needed help in caring for themselves.3 Stroke rates in women increase sharply with age, doubling in each successive decade after the age of 55 years. Stroke incidence is substantially lower in younger women than in age-matched men, but it tends to equalize in the two sexes in the postmenopausal years.1 Thus, stroke is a major health problem for postmenopausal women and one that merits aggressive preventive strategies.

A number of preventive strategies have been proven effective in reducing the risk of stroke. A review of 14 prospective, randomized, controlled trials demonstrated a 42% risk reduction for stroke when the diastolic blood pressure was reduced by 5 to 6 mm Hg,4 and the Systolic Hypertension in the Elderly Program (SHEP) study showed that treating isolated systolic hypertension in the elderly reduced stroke by 36%.5 Similarly, pharmacological intervention with 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statin agents), aspirin, and warfarin in patients with decreased left ventricular function or evidence of left ventricular thrombi after myocardial infarction has proven effective in stroke prevention. Oral anticoagulation and antiplatelet therapy also reduce the risk of stroke in patients with atrial fibrillation, and carotid endarterectomy is effective in preventing stroke in persons with asymptomatic carotid stenosis with 60% to 99% occlusion. Lifestyle modifications, including smoking cessation, …