The population attributable fraction of low education for mortality in South Korea with improvement in educational attainment and no improvement in mortality inequalities

BACKGROUND The educational attainment of Koreans has greatly increased, which was expected to reduce the magnitude of the population attributable fraction (PAF) of mortality associated with low education levels. However, increase in the relative risk (RR) of mortality among those with lower educational levels actually increased the PAF. The purpose of this study was to examine the change in the PAF of lower educational levels for mortality in Korea, where educational attainment has improved and is associated with the exacerbation of inequalities in mortality levels. METHODS National census data were used to derive educational levels. The mortality-associated RR of lower educational levels was calculated by reference to national census and death certificate data from 1995, 2000, 2005, and 2010. PAFs were calculated for all-cause mortality, malignant neoplasms, cerebrovascular disease, heart disease, and suicide by gender and age group (30-44 and 45-59 years). RESULTS The PAF of low educational level in terms of total mortality has decreased since 1995 in both genders. This trend was more prominent among those aged 30-44 years. However, the PAFs of suicide in younger females (30-44 years) and of cerebrovascular disease in older males (45-59 years) have increased. The RRs of all-cause mortality and those of the four leading causes of death in those with the lowest educational levels have increased, especially in females aged 30-44 years. CONCLUSIONS The consistent and sharp increase in the attainment of education has contributed to the reduction in the PAFs of lower education for mortality, despite the fact that mortality inequalities have not improved. Efforts to reduce health inequalities must promote healthy public policy and address public health policies.