English summary: DISPARITY IN LIFE EXPECTANCY BETWEEN INCOME QUINTILES, 1988-2007

Background

Disparities in life expectancy between socioeconomic groups were growing in Finland until the mid-2000s. Various projects aimed at decreasing these disparities have been launched within the framework of the World Health Organization's Health 21 programme. However, to date, trends in life expectancy between income groups have not been monitored. The focus in this study is on the trends among income quintiles compared with the trends among the occupational social classes during the period from 1988 to 2007. Changes in life expectancy among the income quintiles are analysed by cause of death and age group.

Methods

Statistics Finland compiled the data for these analyses from various registers using personal identification codes. The data set includes 754,087 deaths and covers 80 per cent of all deaths in Finland in the period 1988-2007. Household taxable income divided by the number of consumption units was used as the income indicator. Life expectancy at age 35 was calculated on the basis of income quintile and occupational social class for each year. Changes in life expectancy from 1988-1992 to 2003-2007 in the highest and lowest quintiles were decomposed by cause of death and age group.

Results

The disparity in life expectancy at age 35 between the highest and lowest income quintiles widened from 1988 to 2007, from 7.4 to 12.5 years among men and from 3.9 to 6.8 years among women. There was a clear increase in life expectancy in all income quintiles except the lowest, in which it has almost stagnated since the early 1990s. There was less of an increase in disparity between the occupational social classes, and no stagnation among manual workers was observed. Increasing mortality attributable to alcohol-related causes among the working-aged population was a major reason for the adverse development of life expectancy in the lowest income quintile. Moreover, differential trends in mortality from ischaemic heart disease among men and from cancers among women substantially increased the gap between the highest and lowest quintiles.

Conclusions

Life-expectancy differentials between income quintiles have increased more rapidly than differentials based on occupational social class. Occupational social class or education alone may thus be inadequate indicators in the assessment of progress towards the targets set to reduce socioeconomic differentials in mortality, in that they may not take into account adverse developments among those in the most disadvantaged positions in material terms. Health problems related to alcohol, cancer among women and ischaemic heart disease among men in the lowest income quintile should be especially targeted in order to prevent the life-expectancy gap from increasing.