Decomposition of socio-economic differences in life expectancy at birth by age and cause of death among 4 million South Korean public servants and their dependents

作者：Khang Young Ho; Yang Seungmi; Cho Hong Jun; Jung Choi Kyunghee; Yun Sung Cheol^*

来源：International Journal of Epidemiology, 2010, 39(6): 1656-1666.

DOI：10.1093/ije/dyq117

• Life expectancies
• socio-economic differences
• South Korea
• Asia
• cause of death
• mortality

Background Differences in life expectancy at birth across social classes can be more easily interpreted as a measure of absolute inequalities in survival. This study quantified age- and cause-specific contributions to life expectancy differences by income among 4 million public servants and their dependents in South Korea (9.1% of the total Korean population).
Methods Using 9-year mortality follow-up data (208 612 deaths) on 4 055 150 men and women aged 0-94 years, with national health insurance premiums imposed proportionally based on monthly salary as a measure of income, differences in life expectancy at birth by income were estimated by age- and cause-specific mortality differences using Arriaga's decomposition method.
Results Life expectancy at birth gradually increased with income. Differences in life expectancy at birth between the highest and the lowest income quartile were 6.22 years in men and 1.74 years in women. Mortality differentials by income among those aged epsilon 50 years contributed most substantially (80.4% in men and 85.6% in women) to the socio-economic differences in life expectancy at birth. In men, cancers (stomach, liver and lung), cardiovascular diseases (stroke), digestive diseases (liver cirrhosis) and external causes (transport accidents and suicide) were important contributors to the life expectancy differences. In women, the contribution of ill-defined causes was most important. Cardiovascular diseases (stroke and hypertensive disease) and external causes (transport accidents and suicide) also contributed to the life expectancy differences in women while the contributions of cancers and digestive diseases were minimal.
Conclusions Reductions in socio-economic differentials in mortality from stroke and external causes (transport accidents and suicide) among middle-aged and older men and women would significantly contribute to equalizing life expectancy among income groups. Policy efforts to reduce mortality differentials in major cancers (stomach, liver and lung) and liver cirrhosis are also important for eliminating Korean men's socio-economic inequalities in life expectancy.

• 出版日期2010-12