Poverty, process of care, and outcome in acute coronary syndromes

OBJECTIVES: We sought to determine whether income-based disparities in care processes and outcome exist in patients with acute coronary syndromes. BACKGROUND: Using income proxies and limited clinical data, some observational studies have shown income disparities in outcome after acute myocardial infarction (MI). METHODS: Using annual household income from the economic substudy of the PURSUIT (Platelet Glycoprotein IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy) trial, patients were grouped into low-, middle-, and high-income categories based on the U.S. Census Bureau definition of poverty. Logistic regression analysis was used to examine the association between income category and the use of cardiac procedures and the prescription of evidence-based medications at hospital discharge. Cox regression analysis was used to examine the hazard of 30-day and six-month death or recurrent MI across income categories, after adjusting for baseline characteristics. RESULTS: Low-income patients had more chronic medical conditions and were sicker at presentation. Among low-income patients, the use of some evidence-based medications and cardiac procedures was lower and the unadjusted rates of 30-day death and six-month death or MI was higher. After multivariable adjustment, there was no consistent pattern for disparity in care processes, but the trend for higher short and intermediate-term death or MI persisted for low-income patients. CONCLUSIONS: Income level is associated with a trend toward worse outcome among patients with acute coronary syndromes. The disparity in 30-day and six-month death or MI between low and high-income patients could not be readily explained by differences in in-hospital medical or invasive treatment, suggesting that the poor outcomes may be due to differences occurring after hospital discharge.