After correcting for worse baseline characteristics, women treated with thrombolytic therapy for acute myocardial infarction have the same mortality and morbidity as men except for a higher incidence of hemorrhagic stroke. The Investigators of the International Tissue Plasminogen Activator/Streptokinase Mortality Study.

BACKGROUND: In the prethrombolytic era, women with myocardial infarction were reported to have a worse outcome than men. This analysis evaluates the association of sex with morbidity and mortality after thrombolytic therapy. METHODS AND RESULTS: Data were analyzed from 8261 of the 8387 randomized patients with acute myocardial infarction who received thrombolytic therapy in the International Tissue Plasminogen Activator/Streptokinase Mortality Study (baseline data were missing for 126 patients) and were followed for 6 months. Women made up 23% (n = 1944) of the study population. Baseline characteristics were worse in women: they were 6 years older, were more likely to have a history of previous infarction (P < .01), antecedent angina (P < .01), hypertension (P < .0001), or diabetes (P < .0001); were in a higher Killip class on admission (P < .0002); and received thrombolytic therapy 18 minutes later than men (P < .0001). Fewer women were smokers (P < .0001). Women had a higher hospital (12.1% versus 7.2%, P < .0001) and 6-month mortality (16.6% versus 10.4%, P < .0001) and were more likely to develop cardiogenic shock (9.1% versus 6.3%, P < .0001), bleeding (7.2% versus 5.3%, P < .01), and hemorrhagic (1% versus 0.3%, P < .001) or total stroke (2.2% versus 1.1%, P < .0001) during hospitalization. Reinfarction rates and requirement for angioplasty or surgery did not differ. After correction for worse baseline characteristics, women had similar morbidity and mortality apart from a significantly higher incidence of hemorrhagic stroke, which remained significant even after accounting for weight and treatment allocation (odds ratio, 2.90; P < .01). CONCLUSIONS: After thrombolytic therapy for acute myocardial infarction, women have similar morbidity and mortality to men but suffer from a higher incidence of hemorrhagic stroke.