Postmenopausal estrogen use and coronary atherosclerosis.

Study Objective: To determine whether estrogen replacement therapy affects the prevalence of severely obstructive coronary arterial lesions defined by selective coronary arteriography.

Design: Case-control study.

Setting: Large, urban, university-affiliated referral hospital.

Patients: From a consecutive sample of 6452 women having coronary arteriography between 1972 and 1984, 2188 patients were eligible for study; others were excluded because they were nonmenopausal, had congenital heart defects, valvular heart disorders, primary myocardial disease, or no more than mild to moderate coronary artery disease.

Interventions: None.

Measurements And Main Results: Hospital nurses routinely obtained medication histories. Staff invasive cardiologists interpreted coronary arteriograms. Clinical, laboratory, and angiographic data were abstracted from the cardiac catheterization reports and entered into a computerized registry. Postmenopausal estrogen use for 1444 cases of coronary artery disease (70% stenosis) was compared to that 744 controls (0% stenosis). The odds ratio estimate of the risk of coronary artery disease for estrogen users relative to the risk of coronary artery disease for nonusers was 0.44 (95% confidence interval, 0.29 to 0.67) after adjustment for age, cigarette smoking, diabetes, cholesterol, and hypertension. Postmenopausal estrogen replacement was a significant independent protective factor for coronary artery disease in a multivariate logistic regression model (P = 0.037).

Conclusion: The data suggest that postmenopausal estrogen treatment reduces the risk for angiographically significant coronary artery disease.