Income inequality as a social determinant of health

Despite a large body of empirical literature, a consensus has not been reached concerning the health effects of income inequality. This study contributes to ongoing debates by examining the robustness of the income inequality-population health relationship in Argentina, using five different income inequality indexes (each sensitive to inequalities in differing parts of the income spectrum) and five measures of population health. The study is based on an analysis of Argentina's 2001 Encuesta de Condiciones de Vida and provincial rates of male/female life expectancy and infant mortality. The analysis shows that life expectancy is correlated in the expected direction with provincial-level income inequality (operationalised as the Gini coefficient) for both males (r = -0.55, p < 0.01) and females (r = -0.61, p < 0.01), but this association is not robust to all five income inequality indexes. In contrast, infant mortality, self-reported poor health, and self-reported activity limitation are not correlated with any of the income inequality indexes. This study adds further complexity to the study of the health effects of income inequality, by highlighting the importance of effects of operational definitions.