Gender differences in the management and outcome of acute myocardial infarction in unselected patients in the thrombolytic era

This study compares the clinical features, management, and outcome in men and women from a consecutive, unselected series of patients with acute myocardial infarction (AMI) who were admitted to a university cardiac center over a 3-year period. It is a retrospective observational study of 1,059 admissions with AMI identified through the Hospital In-Patient Enquiry (HIPE) registry, validated according to Minnesota Manual criteria, and followed for a period of up to 5 years (median 36 months). Women comprised 40% of all admissions, had a higher hospital mortality (24% vs 16%, p <0.001), and were less likely to receive thrombolysis (23% vs 33%, p <0.01), admission to coronary care (65% vs 77%, p <0.001), or subsequent invasive or noninvasive investigations (55% vs 63%, p <0.01). However, women with AMI were older than men with AMI (71 vs 65 years, p <0.001). After adjusting for age, differences that remained significant were prevalence of hypertension (odds ratio [OR] 2.12, 95% confidence intervals [CI] 1.56 to 2.88) and cigarette smoking (OR 0.47, 95% CI 0.35 to 0.65), management in coronary care (OR 0.66, 95% CI 0.49 to 0.88), and hospital mortality (OR 1.48, 95% CI 1.07 to 2.04). Excess mortality occurred predominantly in women <65 years old (18% vs 8%, OR [multivariate] 2.35, 95% CI 1.19 to 4.56), among whom multivariate analysis demonstrated a significantly lower thrombolysis rate (OR 0.48, 95% CI 0.27 to 0.86). In this group, lack of thrombolysis independently predicted hospital mortality (OR 5.37, 95% CI 1.45 to 19.82). Female gender was not an independent predictor of mortality following AMI (OR 1.42, 95% CI 0.90 to 2.26). Thus, among unselected patients, female gender is associated with, but not an independent predictor of, reduced survival after AMI. Gender differences in mortality are greatest in younger patients, who are less likely to receive thrombolysis and in whom lack of thrombolysis is independently associated with mortality after AMI.