US State-level income inequality and risks of heart attack and coronary risk behaviors: longitudinal findings.

Abstract

To examine prospectively the association between US state income inequality and incidence of heart attack. We used data from the National Epidemiologic Survey on Alcohol and Related Conditions (n = 34,445). Respondents completed interviews at baseline (2001-2002) and follow-up (2004-2005). Weighted multilevel modeling was used to determine if US state-level income inequality (measured by the Gini coefficient) at baseline was a predictor of heart attack during follow-up, controlling for individual-level and state-level covariates. In comparison to residents of US states in the lowest quartile of income inequality, those living in the second [Adjusted Odds Ratio (AOR) = 1.71, 95 % CI 1.16-2.53)], third (AOR = 1.81, 95 % CI 1.28-2.57), and fourth (AOR = 2.04, 95 % CI 1.26-3.29) quartiles were more likely to have a heart attack. Similar findings were obtained when we excluded those who had a heart attack prior to baseline. This study is one of the first to empirically show the longitudinal relationship between income inequality and coronary heart disease. Living in a state with higher income inequality increases the risk for heart attack among US adults.