Life expectancy at birth
Life expectancy at birth continues to increase remarkably in Asia-Pacific, reflecting sharp reductions in mortality rates at all ages, particularly among infants and children (see indicators “Infant mortality” and “Under age 5 mortality” in Chapter 3). These gains in longevity can be attributed to a number of factors, including rising living standards, better nutrition and improved drinking water and sanitation facilities (see indicator “Water and sanitation” in Chapter 4). Improved lifestyles, increased education and greater access to quality health services also play an important role (National Institute on Ageing, National Institute of Health and WHO, 2011).
Life expectancy at birth for the whole population across low and lower-middle Asia-Pacific countries and territories reached 69.9 years on average in 2016, a gain of about 5.8 years since 2000, whereas it reached 74.3 years in upper-middle income countries, a gain of about 3.6 years since 2000. In comparison, OECD countries gained 3.1 years during the same period (Figure 3.1, left panel).
However, a large regional divide persists in life expectancy at birth. The country with the longest life expectancy in 2016 was Japan with 84.2 years. Hong Kong, China, Singapore, Australia, New Zealand, the Republic of Korea and Macau, China also exceeded 80 years for total life expectancy. In contrast, ten countries in the Asia-Pacific region had total life expectancies of less than 70 years, and in Lao PDR a child born in 2016 can expect to live an average of less than 66 years.
Women live longer than men (Figure 3.1, right panel) do, but the degree of disparities varies across countries. The gender gap in life expectancy stood at 4.7 and 5.4 years on average across Asia-Pacific low and lower-middle, and upper-middle countries respectively in 2016, less than the OECD country average of 5.6 years. The gender difference was particularly large in Viet Nam and Mongolia with eight years or longer, while Pakistan reported a gender gap of less than two years. Women also have greater rates of survival to age 65 (Figure 3.2), regardless of the economic status of the country. On average, 77.6% and 84.5% of a cohort of newborn infant females would survive to age 65 in low and lower-middle, and upper-middle income Asia-Pacific countries respectively, while only 67.3% and 74.4% of males will survive to age 65 in low and lower-middle, and upper-middle income Asia-Pacific countries respectively. In Japan, the Republic of Korea, Hong Kong, China and Macau, China 94% of newborn infant females will survive to age 65, whereas in Mongolia and Papua New Guinee less than three out of five newborn infant males will survive to age 65. Many reasons contribute to this gender difference, such as biological differences resulting in slower ageing of immune systems and the later onset of cardiovascular diseases such as heart attacks and strokes among women (UNESCAP, 2017).
Higher national income – as measured by GDP per capita – is generally associated with higher life expectancy at birth (Figure 3.3). There were, however, some notable differences in life expectancy between countries with similar income per capita. Nepal and Bangladesh had higher, and Mongolia and Indonesia had lower life expectancies than predicted by their GDP per capita alone. Socioeconomic status and education play an important role in life expectancy as seen in the case of Japan, where the higher educational background of mothers and household wealth are associated with better infant and child survival (see indicators “Infant mortality” and “Under age 5 mortality” in Chapter 3).
Life expectancy at birth is the best-known measure of population health status, and is often used to gauge a country’s health development. It measures how long, on average, a newborn infant can expect to live if current death rates do not change. Since the factors affecting life expectancy often change slowly, variations are best assessed over long periods.
Age-specific mortality rates are used to construct life tables from which life expectancies are derived. The methodologies that countries use to calculate life expectancy can vary somewhat, and these can lead to differences of fractions of a year. Some countries base their life expectancies on estimates derived from censuses and surveys, and not on accurate registration of deaths.
Survival to age 65 refers to the percentage of a cohort of newborn infants that would survive to age 65, if subject to current age-specific mortality rates.
Source: OECD Health Statistics 2018; the World Bank World Development Indicators Online.
Source: The World Bank World Development Indicators Online.
Source: OECD Health Statistics 2018; The World Bank World Development Indicators Online.