Postmenopausal Hormone Therapy and Risk of Stroke. The Heart and Estrogen-Progestin Replacement Study (HERS) - HERS Stroke Study


Postmenopausal Hormone Therapy and Risk of Stroke. The Heart and Estrogen-Progestin Replacement Study (HERS).


The risk of stroke associated with postmenopausal hormone replacement therapy (HRT) is not clear. This study sought to determine the effects of HRT on stroke and transient ischemic attacks (TIA) in postmenopausal women with coronary heart disease (CHD) enrolled in HERS, which evaluated the effects of 0.625mg conjugated estrogen and 2.5mg progestin in CHD.

Study Design

Study Design:

Patients Enrolled: 2763
Female: 100

Drug/Procedures Used:

Postmenopausal women with CHD (n = 2763) were randomly assigned to HRT vs. placebo and followed for a mean of 4.1 years. Stroke and TIA were prespecified secondary outcomes in HERS.

Principal Findings:

Average age was 67 years, 68% were hypertensive, 23% diabetics, ASA was used in 79% and lipid levels were relatively normal. A total of 149 women (5%) had one or more strokes (85% ischemic) and 26 were fatal. HRT was not significantly associated with nonfatal or fatal strokes. Independent predictors of stroke included increasing age, hypertension, diabetes, current cigarette smoking, and atrial fibrillation. BMI was inversely related to stroke.

Hormone therapy with estrogens and progestins in postmenopausal women with CHD had no significant effect on the risk for stroke or TIAs.


The incidence of stroke in HERS was over twice that in white women aged 45–84 years (4/1000 person-years), a finding likely explained by the association of cerebral and carotid disease with CHD and shared risk factors. The findings are important since if the subset of patients with CHD for whom there is a risk of early thrombotic events can be distinguished, the long-term benefits of HRT on CHD risk reduction should be obtained without an increased risk of neurologic events.


1. Simon JA, Hsia J, Cauley JA, et al. for the HERS Research Group. Circulation 2001;103:638–42.

Clinical Topics: Prevention, Hypertension, Smoking

Keywords: Progestins, Stroke, Ischemic Attack, Transient, Body Mass Index, Postmenopause, Estrogens, Risk Factors, Estrogen Replacement Therapy, Hypertension, Diabetes Mellitus, Smoking

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