Socioeconomic Disadvantage and Acute Coronary Events

Abstract

The associations between socioeconomic disadvantage and ischemic heart disease are not well understood. We explore the relationship between socioeconomic factors and acute coronary events using spatiotemporal analysis. We studied all deaths from acute myocardial infarction and hospital admissions for acute coronary syndrome and related revascularization procedures for the state of New South Wales, Australia, from 1996 through 2002. We used conditional autoregressive models to describe how characteristics of subjects' place of residence (socioeconomic disadvantage, proportion of the population of indigenous background, and metropolitan versus nonmetropolitan area) influenced admissions and mortality. There were 32,534 deaths due to acute myocardial infarction and 129,045 admissions for acute coronary syndrome. We found a relationship between increasing socioeconomic disadvantage and mortality (unadjusted relative risk for highest quartile of disadvantage relative to lowest = 1.40; 95% confidence interval = 1.27-1.54) as well as admissions (1.41; 1.28-1.55). After accounting for admission rates, socioeconomic disadvantage was associated with lower rates of angiography (0.75; 0.63-0.88) and interventional angiography (0.70; 0.56-0.85). After adjusting for socioeconomic disadvantage, areas with higher proportions of the population identified as indigenous had higher rates of admission and mortality, while residency in the state capital was associated with higher admission rates and more interventional angiography. After accounting for admission rates, the association of socioeconomic disadvantage with mortality was reduced. Socioeconomic disadvantage increases both the risk of acute coronary syndrome and related mortality. A contributing factor appears to be a reduced chance of receiving appropriate care. Regions with a higher proportion of indigenous residents show risk beyond the effects of general socioeconomic disadvantage, while residents of metropolitan communities had increased utilization of more recent interventions.