Income, inequality and mortality in 14 developed countries

The tendency for more egalitarian societies to have lower mortality rates has been identified in international data and subsequently confirmed in analyses of areas within countries, particularly within the USA. However, recent reports using data on OECD countries from the Luxembourg Income Study (LIS) suggest this relation no longer exists. We investigated whether the shift in relative poverty from elderly people (with high death rates) to young families (low death rates) may have affected the associations. Using age- and sex-specific mortality among 14 OECD countries in relation to income inequality, median income and absolute and relative poverty, we found that wider income distribution is related to higher premature mortality, and higher age-specific mortality rates below, but not above, age 65 years. Absolute income levels showed no consistent relation to mortality. The changing age distribution of relative poverty may have affected the way income inequality impacts on mortality measured across all ages.