Risk of recurrent coronary events in relation to use and recent initiationof postmenopausal hormone therapy

Background: The finding from the Heart and Estrogen/Progestin Replacement S tudy (HERS) of increased coronary risk restricted to the first year after s tarting postmenopausal hormone therapy raises new questions about the role of hormone therapy in women with coronary heart disease. We assessed the ri sk of recurrent myocardial infarction or coronary heart disease death assoc iated with the use and recent initiation of hormone therapy in women who su rvived a first myocardial infarction. Methods: The setting for this population-based inception cohort study was G roup Health Cooperative, a health maintenance organization. We studied 981 postmenopausal women who survived to hospital discharge after their first m yocardial infarction between July 1, 1986, and December 31, 1996. We obtain ed information on hormone use from the Group Health Cooperative computerize d pharmacy database and identified recurrent coronary events by medical rec ord review. Results: During median follow-up of 3.5 years, there were 186 recurrent cor onary events. There was no difference in the risk of recurrent coronary eve nts between current users of hormone therapy) and other women (adjusted rel ative hazard [RH], 0.96; 95% confidence interval [Cl], 0.62-1.50). Relative to the risk in women not currently using hormones, there was a suggestion of increased risk during the first 60 days after starting hormone therapy ( RH, 2.16; 95% CI, 0.94-4.95) and reduced risk with current hormone use for longer than 1 year (RH, 0.76; 95% CI, 0.42-1.36). Conclusion: These results are consistent with the findings from the HERS, s uggesting a transitory increase in coronary risk after starting hormone the rapy in women with established coronary heart disease and a decreased risk thereafter.