Introduction: African American (AA) women have a higher incidence of major adverse cardiac events (MACE), including all-cause death, nonfatal myocardial infarction, nonfatal stroke, and angina/heart failure hospitalizations, compared to non-AA. If this is explained by risk variables, including obstructive coronary artery disease (CAD), is unknown. We compared risk factors and longer-term MACE stratified by ethnicity in the Women’s Ischemia Syndrome Evaluation.
Methods: Historical and clinical variables were collected and the presence of CAD (≥50% stenosis on angiography) was determined. CAD severity index was ascertained with the Sharaf-Gensini system. Participants were contacted at 6 weeks and then annually to assess for MACE. Differences in risk variables, CAD, and MACE were assessed.
Results: 164/944 (17.4%) were AA. AA had higher body-mass index, blood pressure, glucose, heart rate, total cholesterol, triglycerides, Duke Activity Score Index, antihypertensive agent use, disability, and lower education, marital status, income, home activity, menopause and insurance (p<0.05). There were no differences in CAD prevalence (42% vs. 38%, p=0.3319), or CAD Severity Score (15.5±15.8 vs 14.7±14.5, p=0.55) between AA and non-AA. Multivariate analysis demonstrated a trend toward higher MACE in AA (p=0.08). In sub-group analysis, this trend was evident in the CAD cohort (Figure 1A); however, worse MACE was observed in AA with no CAD (Figure 1B). Adjustment for baseline differences including higher statin and renin-angiotensin system blocker use in the no obstructive CAD AA did not alter the results.
Conclusions: Greater risk factor burden yet similar CAD burden was observed in AA vs non-AA. Longer-term mortality adjusted for these variables trended toward more adverse MACE in AA vs non-AA, with the greatest difference in women with no obstructive CAD. Further investigation is warranted to understand relations between ethnicity and no obstructive CAD in women.