Differences between women and men in survival after myocardial infarction. Biology or methodology?

To examine the impact of gender on survival after myocardial infarction, we performed a retrospective cohort study of 332 women and 790 men. Women who had a myocardial infarction were older and more often had hypertension, diabetes, previous heart failure, and impaired left ventricular function on admission. Cumulative 3-year mortality and in-hospital mortality rates were significantly higher in women than men, but mortality among hospital survivors was similar. After multivariate adjustment for baseline differences, mortality rates were not significantly different between women and men for in-hospital deaths, and mortality at 3 years among hospital survivors tended to be lower among women. We conclude that higher observed mortality rates following a myocardial infarction in women are related to differences in known risk factors for subsequent mortality and that gender should not be considered an independent risk factor for mortality after myocardial infarction.