ESTROGEN REPLACEMENT THERAPY AND PROGNOSIS AFTER FIRST MYOCARDIAL-INFARCTION

The effects of estrogen replacement therapy on prognosis in women with established coronary disease remain uncertain. The authors conducted a retrospective cohort study of 726 women (mean age, 66.2 years) who s urvived first myocardial infarction to hospital discharge from 1980 th rough 1991,while enrolled at Group Health Cooperative of Puget Sound i n western Washington State. Estrogen replacement therapy after myocard ial infarction (122 women) was ascertained from computerized pharmacy records. Reinfarctions (n = 135) and deaths (n = 183) through 1993 wer e identified, and relative risks were calculated. The relative risk fo r reinfarction associated with current estrogen replacement therapy af ter myocardial infarction, adjusting for age and time since infarction , was 0.64 (95% confidence interval (Cl) 0.32-1.30), and that for past estrogen replacement therapy was 0.90 (95% Cl 0.62-1.31). The relativ e risk for ail-cause mortality associated with current estrogen replac ement therapy was 0.50 (95% Cl 0.25-1.00), and that for past estrogen replacement therapy was 0.79 (95% Cl 0.56-1.09). While estrogen users were less likely than nonusers to have a history of diabetes or conges tive heart failure, adjustment for these and additional prognostic fac tors altered risk estimates only slightly. Estrogen replacement therap y after first myocardial infarction was not associated with increased risk of reinfarction or mortality. This study provides reassurance reg arding the safety of estrogen replacement therapy after myocardial inf arction in women.