POSTMENOPAUSAL ESTROGENS AND RISK OF MYOCARDIAL-INFARCTION IN DIABETIC WOMEN

OBJECTIVE-The effect of hormone replacement therapy on the risk of myo cardial infarction in diabetic women has not been well studied. We con ducted a case-control study of postmenopausal estrogen use and risk of incident myocardial infarction (MI) in pharmacologically treated diab etic women enrolled at Group Health Cooperative of Puget Sound, a larg e health maintenance organization in the state of Washington. RESEARCH DESIGN AND METHODS-Case subjects (n = 212) were all postmenopausal wo men with treated diabetes who sustained an incident fatal or nonfatal MI between July 1986 and December 1994. Control subjects (n = 122) wer e treated diabetic women drawn from a stratified random sample of post menopausal women without prior MI. Computerized pharmacy data and medi cal records were used to measure use of estrogens. Cardiovascular risk factors recorded from medical records, computerized pharmacy and labo ratory data, and telephone interviews were used as adjustment variable s. RESULTS-In this study, 8.5% of case and 13.9% of control subjects w ere current users of estrogens. The relative risk (RR) of MI for curre nt estrogen users was 0.51 (95% CI 0.22-1.15) relative to never users, adjusted for age, study year, weight, angina, and duration of treated diabetes. Among current estrogen users, risk of MI tended to decline with each additional year of estrogen use (adjusted RR = 0.78, 95% CI 0.56-1.08). Of those studied, 45.3% of case and 37.7% of control subje cts were past users of estrogens (adjusted RR = 1.22, 95% CI 0.71-2.09 ). CONCLUSIONS-This study suggests that use of postmenopausal estrogen s does not increase risk of MI in diabetic women and that sustained us e may be of benefit.