What Contributed to the Large Sex Differentials in Lifespan Variation and Life Expectancy in South Korea

Younga Kim, Université catholique de Louvain
Akansha Singh, Universite Catholique de Louvain

South Korean women is predicted to break the 90-year barrier by 2030. Does life disparity by gender tell same story with such gains in life expectancy? To date, almost all of the research on mortality variation were from Western countries, but there is a dearth of such studies from South Korea. We fill this important gap in understanding of mortality transition in terms of life expectancy change and associated trajectories of age-at-death variation through life disparity by gender in South Korea. Using complete life tables of South Korea from 1970-2015, we analyse the change in sex differentials in life disparity and life expectancy over time and decompose these sex differentials by age and cause of death. The results show that the sex differentials in life disparity has widened in 1970s and 80s and remained stagnant thereafter until 2015 along with life expectancy. Females enjoy higher life expectancy and have lower life disparity in 2015 mainly due to lower mortality of middle age (40-60 years) and old age (60-80 years). However, higher life expectancy for females in 1970 was not translated into lower life disparity due to higher mortality of adult age (25-30 years) and old age (60+).

  1. INTRODUCTION

Variability in lifespan can be measured through various indicators. Life disparity is the indicator used to measure lifespan variation in the recent decades. In high longevity population, life expectancy has increased at all ages but the life disparity had not declined uniformly across all ages (Vaupel et al., 2011). Moreover, even at the similar level of life expectancy at birth, life disparity exhibits substantial cross-country differentials. These differentials were attributed to the difference in the age structure and causes of mortality. Most of the studies suggested that the female advantage is vigilant in dispersion measures of age at death such as life disparity (Shkolnikov et al., 2011).

South Korea, as one of two Asian nations of OECD member countries, is rarely studied, unlike its counterpart, Japan (for example, Shkolnikov et al., 2011; Vaupel et al., 2011), has been mainly examined in life disparity literature. Life expectancy at birth of South Korea has risen dramatically during the past few decades. The life expectancy increased significantly for both men and women, although women still live much longer than men. Gender differences in life expectancy varied over time: the gap increased till 1979, reaching the peak of more than 8 years in 1980s, stagnated from 1979 to 1992, and decreased steadily thereafter till 2005 (Yang, Khang, Chun, Harper, & Lynch, 2012). Declining gender gap in life expectancy since 1990s comes from a greater pace of the improving male mortality than that of females. Although the reductions of infant and childhood mortality contributed to both increased life expectancy and gender gap in life expectancy, their contributions have decreased over the decades (Yang et al., 2010, 2012).

With the significant reduction in mortality, there are high chances of reducing variation of deaths in South Korea. However, inequalities in life expectancy has rather attracted the most attention than variation in lifespan, by examining how life expectancy differ by gender (Yang et al., 2012), income (Khang, Bahk, Yi, & Yun, 2016), education (Son et al., 2012; Jung-Choi, Khang, Cho, & Yun, 2014). However, life disparity changes during the same period remain unexplored. South Korean women is predicted to break the 90-year barrier by 2030 (Kontis et al., 2017). Does life disparity by gender tell same story with such gains in life expectancy? More specifically, is lifespan variation of South Korean decreasing, along with the increase in life expectancy like the observed negative relation between high life expectancy and low life disparity in most countries (Vaupel et al., 2011; Singh & Ladusingh, 2013), or is the life disparity increasing over time, as the United states did (Edwards & Tuljapurkar, 2005)?

Our objective is to assess the mortality decline from the perspective of both life disparity and life expectancy. Using life tables, 1970-2015 and cause-elimination life tables, 1995-2015 from South Korean National Statistics Office, we analyse the change in sex differentials in life disparity and life expectancy over time in South Korea and decompose these sex differentials by age and cause of death.

  1. DATA AND METHODS

We use complete life tables from 1970 to 2015 from South Korean National Statistics Office (South Korean National Statistics Office, 2017). We calculate annual life expectancy and life disparity at birth between 1970 and 2015 for males and females. Decomposition of life female-male difference in life expectancy at birth and life disparity was done using a spreadsheet developed by Shkolnikov and Andreev (2011).

  1. RESULTS

With increasing life expectancy, life disparity has reduced over time for both males and females in South Korea. Although females enjoyed higher life expectancy in 1970 but the life disparity was higher, a contrast to what has been observed in the other European countries. However, female’s life disparity get lower than male life disparity in 1981, the same year when the sex difference in life expectancy was the highest. The difference in life disparity was maximum (2.0 years) in the year 2001. However, no significant reduction the difference in life disparity has been observed from the last 14 years. The female advantage in life expectancy in 1970 was mainly attributed to the small contribution of infant and young adult age group and the large contribution from almost each age after 40 years and above. Although, there has been a shift in the age contribution with large contribution of the old age group in 2015. Female’s higher life expectancy is not translated into lower life disparity in 1970 mainly due to due to higher life disparity contribution from adult age (25-30 years) and old age (60+). However, a significant change in female life disparity has occurred in the last 40 years in South Korea and their mortality advantage is even observed for life disparity now. Decomposition of female-male difference in life disparity in 2015 suggests that the female from infant to old age contributes to reduce life disparity.

Presented in Session 1232: Mortality and Longevity