Cause-specific mortality and income inequality in S？o Paulo, Brazil

objective: to analyze cause-specific mortality rates according to the relative income hypothesis. methods: all 96 administrative areas of the city of s？o paulo, southeastern brazil, were divided into two groups based on the gini coefficient of income inequality: high (>0.25) and low (<0.25). the propensity score matching method was applied to control for confounders associated with socioeconomic differences among areas. results: the difference between high and low income inequality areas was statistically significant for homicide (8.57 per 10,000; 95%ci: 2.60;14.53); ischemic heart disease (5.47 per 10,000 [95%ci 0.76;10.17]); hiv/aids (3.58 per 10,000 [95%ci 0.58;6.57]); and respiratory diseases (3.56 per 10,000 [95%ci 0.18;6.94]). the ten most common causes of death accounted for 72.30% of the mortality difference. infant mortality also had significantly higher age-adjusted rates in high inequality areas (2.80 per 10,000 [95%ci 0.86;4.74]), as well as among males (27.37 per 10,000 [95%ci 6.19;48.55]) and females (15.07 per 10,000 [95%ci 3.65;26.48]). conclusions: the study results support the relative income hypothesis. after propensity score matching cause-specific mortality rates was higher in more unequal areas. studies on income inequality in smaller areas should take proper accounting of heterogeneity of social and demographic characteristics.