Association of Socioeconomic Status with One-Year Readmission and Mortality among Patients with Acute Myocardial Infarction

Background: Mortality and morbidity are known to be negatively associated with socioeconomic status (SES). This research aims to investigate the magnitude of this association at the individual level: household income (a proxy for the SES) and cardiovascular disease (CVD). CVD accounts for almost one-third of deaths in the world and one-fourth of deaths in the United States. Given the size of CVD incidence and its severity, we examined how it occurs across various levels of SES. Methods: The zip-code based median household income data in the U.S. Census Bureau were matched to CVD patients from the Myocardial Infarction Data Acquisition System (MIDAS), a rich database that comprises cardiovascular admissions to acute care hospitals in New Jersey. Logistic Regression and Cox Proportional Hazards models were applied to study the relationship between income and three cardiovascular clinical outcomes: readmission for acute myocardial infarction (AMI readmission), cardiovascular death (CV death), and all-cause death among patients with a first admission for AMI, while controlling for covariates available in the database, including demographic factors, insurance types, and comorbidities. Results: The main results indicate that patients at the lowest income level had higher risk for AMI readmission and CV death, but not for all-cause death. Ceteris paribus, the chance of one-year AMI readmission increases with lower income levels according to the Logistic Regression outcomes. Conclusions: Our findings may help better allocate limited resources to where they are in greater need, so the costly and deadly incidence of heart disease can be reduced.