Has the relation between income inequality and life expectancy disappeared? Evidence from Italy and top industrialised countries.

OBJECTIVE To investigate the relation between income inequality and life expectancy in Italy and across wealthy nations. DESIGN AND SETTING Measure correlation between income inequality and life expectancy at birth within Italy and across the top 21 wealthy countries. Pearson correlation coefficients were calculated to study these relations. Multivariate linear regression was used to measure the association between income inequality and life expectancy at birth adjusting for per capita income, education, and/or per capita gross domestic product. DATA SOURCES Data on the Gini coefficient (income inequality), life expectancy at birth, per capita income, and educational attainment for Italy came from the surveys on Italian household on income and wealth 1995-2000 and the National Institute of Statistics information system. Data for industrialised nations were taken from the United Nations Development Program's human development indicators database 2003. RESULTS In Italy, income inequality (beta = -0.433; p<0.001) and educational attainment (beta = 0.306; p<0.001) were independently associated with life expectancy, but per capita income was not (beta = 0.121; p>0.05). In cross national analyses, income inequality had a strong negative correlation with life expectancy at birth (r = -0.864; p<0.001). CONCLUSIONS In Italy, a country where health care and education are universally available, and with a strong social safety net, income inequality had an independent and more powerful effect on life expectancy at birth than did per capita income and educational attainment. Italy had a moderately high degree of income inequality and an average life expectancy compared with other wealthy countries. The cross national analyses showed that the relation between income inequality and population health has not disappeared.