Importance of socioeconomic status as a predictor of cardiovascular outcome and costs of care in women with suspected myocardial ischemia. Results from the national institutes of health, national heart, lung and blood institute-sponsored Women's Ischemia Syndrome Evaluation (WISE)

Background: For women, who are more likely to live in poverty, defining the clinical and economic impact of socioeconomic factors may aid in defining redistributive policies to improve healthcare quality. Methods. The NIH-NHLBI-sponsored Women's Ischemia Syndrome Evaluation (WISE) enrolled 819 women referred for clinically indicated coronary angiography. This study's primary end point was to evaluate the independent contribution of socioeconomic factors on the estimation of time to cardiovascular death or myocardial infarction (MI) (n = 79) using Cox proportional hazards models. Secondary aims included an examination of cardiovascular costs and quality of life within socioeconomic subsets of women. Results: In univariable models, socioeconomic factors associated with an elevated risk of cardiovascular death or MI included an annual household income <$20,000 (p = 0.0001), <9th grade education (p = 0.002), being African American, Hispanic, Asian, or American Indian (p = 0.016), on Medicaid, Medicare, or other public health insurance (p < 0.0001), unmarried (p = 0.001), unemployed or employed part-time (p < 0.0001), and working in a service job (p = 0.003). Of these socioeconomic factors, income (p = 0.006) remained a significant predictor of cardiovascular death or MI in risk-adjusted models that controlled for angiographic coronary disease, chest pain symptoms, and cardiac risk factors. Low-income women, with an annual household income <$20,000, were more often uninsured or on public insurance (p < 0.0001) yet had the highest 5-year hospitalization and drug treatment costs (p < 0.0001). Only 17% of low-income women had prescription drug coverage (vs. ≥50% of higher-income households, p < 0.0001), and 64% required ≥2 anti-ischemic medications during follow-up (compared with 45% of those earning ≥$50,000, p < 0.0001).