Socioeconomic inequalities in all-cause and specific-cause mortality in Australia: 1985-1987 and 1995-1997

BACKGROUND: Socioeconomic inequalities in mortality have been repeatedly observed in Britain, the US, and Europe, and in some countries there is evidence that the differentials are widening. This study describes trends in socioeconomic mortality inequality in Australia for males and females aged 0-14, 15-24 and 25-64 years over the period 1985-1987 to 1995-1997. METHODS: Socioeconomic status (SES) was operationalized using the Index of Relative Socioeconomic Disadvantage, an area-based measure developed by the Australian Bureau of Statistics. Mortality differentials were examined using age-standardized rates, and mortality inequality was assessed using rate ratios, gini coefficients, and a measure of excess mortality. RESULTS: For both periods, and for each sex/age subgroup, death rates were highest in the most disadvantaged areas. The extent and nature of socioeconomic mortality inequality differed for males and females and for each age group: both increases and decreases in mortality inequality were observed, and for some causes, the degree of inequality remained unchanged. If it were possible to reduce death rates among the SES areas to a level equivalent to that of the least disadvantaged area, premature all-cause mortality for males in each age group would be lower by 22%, 28% and 26% respectively, and for females, 35%, 70% and 56%. CONCLUSIONS: The mortality burden in the Australian population attributable to socioeconomic inequality is large, and has profound and far-reaching implications in terms of the unnecessary loss of life, the loss of potentially economically productive members of society, and increased costs for the health care system.