Longitudinal relation of community-level income inequality and mortality in Costa Rica

Abstract

The controversy regarding the direct relationship between income distribution and health remains unresolved. Empirical evidence has often failed to advance our understanding because in the countries studied there was limited ability to distinguish hypotheses. This study examines the relation between inequality and mortality in the context of Costa Rica. Costa Rica's unique social and political structure makes confounding through resource and political channels less likely, thus any effects would work predominantly through direct psychosocial channels. Using mortality data extracted from the Vital Statistics Registry, we evaluate the longitudinal relations between lagged and contemporaneous income inequality and cause-specific mortality in Costa Rica from 1995 to 2005. For those aged 15-60, results indicate that there is a significant adverse relation between increases in lagged inequality and mortality from liver disease, and marginal adverse relations with mortality from diabetes and suicide. For those aged 60 and over, there is a limited evidence of a relation between inequality and health. These results suggest increases in inequality may impact health behavior of the working aged population in Costa Rica.

Figure 1

Percentage change in household equivalent income from 1987 to 2005 by income percentile. Source: Author's calculation based on Costa Rican Household Survey for Multiple Purposes and Costa Rican CPI deflators found at Banco Central De Costa Rica (http://indicadoreseconomicos.bccr.fi.cr). All colones adjusted to 2006 colones.