Sex and Ethnic Differences in Outcomes of Acute Coronary Syndrome and Stable Angina Patients With Obstructive Coronary Artery Disease

BACKGROUND: The joint contribution of sex, ethnicity, and initial clinical presentation to the long-term outcomes of patients undergoing coronary angiography for acute coronary syndrome (ACS) or stable angina, in whom there is angiographic evidence for obstructive coronary artery disease, remains unknown. METHODS AND RESULTS: We conducted a population-based cohort study on 49 556 adult ACS or stable angina patients with angiographic evidence of obstructive coronary artery disease (≥ 50% stenosis) in British Columbia. The 2-year composite outcome was all-cause death and hospital readmissions for myocardial infarction, heart failure, cerebrovascular accident, or angina after the index angiography. Sex and ethnic differences in the composite outcome were examined by clinical presentation using the Cox proportional-hazards and logistic regression models. Overall, 25.6% were women, 9.5% were South Asians, 3.0% were Chinese, and 65.9% presented with ACS. Regardless of ethnicity, women were more likely than men to have adverse outcomes, but the magnitude of the sex difference was greater in the ACS patients (P(interaction) for sex and clinical presentation=0.03). Angina readmission accounted for 45% of the composite outcome and was the main component for all groups with the exception of Chinese women with ACS. Furthermore, women were more likely than men to be readmitted for angina (odds ratio 95% confidence interval, 1.13 1.04-1.22). CONCLUSIONS: Higher rates of adverse events among women with obstructive coronary artery disease, regardless of ethnicity, as well as high rates of angina readmission, highlight the need for more targeted interventions to reduce the burden of angina because this presentation is clearly not benign.