Today, the Lancet published our study projecting life expectancy trends to 2030 for 35 countries:
Life expectancy at birth is projected to exceed 90 years for Korean women in 2030, a level of average life expectancy many thought impossible to achieve. South Korean men are also likely to lead at 84.1 years, closely followed by Switzerland and Australia. The USA is likely to have the lowest life expectancy at birth in 2030 among high-income countries, with levels similar to that of middle-income countries like Croatia and Mexico. My colleague, Professor Majid Ezzati at Imperial College London, says this may be due to a number of factors including a lack of universal affordable access to health services, as well as the highest child and maternal mortality rate, homicide rate and obesity among high-income countries.
The study was led by Majid Ezzati at Imperial College, London, with much of the statistical work carried out by Vasilis Kontis and James Bennett. I collated the country mortality data from the WHO Mortality Database and contributed to the development of the methodology and the interpretation of results. Countries in the study included both high-income countries, such as the USA, Canada, UK, Germany, Australia, and emerging economies such as Poland, Mexico and the Czech Republic. The methods involved development and averaging of an ensemble of 21 Bayesian forecasting models, all of which contributed probabilistically to the final projections. The Bayesian model averaging (BMA) resulted in smaller projection errors than the best single model. The projection errors were assessed by projecting withheld data.
The BMA projections resulted in probability distributions of life expectancy in 2030. The paper included graphical presentations of these posterior probability distributions, as shown in the Figure above for projected life expectancy at birth. The red dots indicate the median projected life expectancy, and countries are ordered vertically by this median. A baby girl born in South Korea in 2030 will expect to live 90.8 years (median projection). Life expectancy at birth for South Korean men will be 84.1 years. The British Telegraph newspaper also reproduced one of these graphs, and I suspect it is the first time a tabloid newspaper has given its readers information on Bayesian posterior probability distributions for anything.
The study also calculated how long a 65-year-old person may expect to live in 2030. The results revealed that the average 65-year-old woman in South Korea in 2030 may live an additional 27.5 years, resulting in an average age at death of 92.5 years.
James Fries in the late 1980s argued that the 85 years represented the upper limit of human life expectancy at population level (the upper limit of individual longevity is somewhere above 120 and probably at present below 130). Others such as Olshansky have also forcefully argued that we will not see much more substantial progress in life expectancy. However this study suggests we will break the 90-year barrier, and we may still be a long way from the upper limit of life expectancy – if there is one.
I spoke about the results of this study today on the BBC World Service and on the BBC television news. They also published an article on their website:
Other findings from the study include:
- The five countries with the highest life expectancy at birth for men in 2030 were: South Korea (84.1), Australia (84.0), Switzerland (84.0), Canada (83.9), Netherlands (83.7)
- The five countries with the highest life expectancy at birth for women in 2030 were: South Korea (90.8), France (88.6), Japan (88.4), Spain (88.1), Switzerland (87.7)
- The five countries with the highest life expectancy for 65-year-old men in 2030 were: Canada (22.6 additional life years), New Zealand (22.5), Australia (22.2), South Korea (22.0), Ireland (21.7)
- The five countries with the highest life expectancy for 65-year-old women in 2030 were: South Korea (27.5 additional life years), France (26.1), Japan (25.9), Spain (24.8), Switzerland (24.6)
- The five countries in Europe with the highest life expectancy at birth for men in 2030 were: Switzerland (84.0), Netherlands (83.7), Spain (83.5), Ireland (83.2) and Norway (83.2)
- The five countries in Europe with the highest life expectancy at birth for women in 2030 were: France (88.6), Spain (88.1), and Switzerland (87.7), Portugal (87.5) and Slovenia (87.4).
- The UK’s average life expectancy at birth for women will increase from 82.3 years in 2010 to 85.3 years in 2030. This places them 21st in the table of 35 countries (compared to 22nd in 2010).
- The average life expectancy of a UK man at birth will increase from 78.3 years in 2010 to 82.5 years in 2030. This places them 14th in the table of 35 countries (compared to 11th in 2010).