Life expectancy around the world has increased significantly over the past century, with Australia among the best performing countries.
But over the past two decades, some high-income countries have reported stagnation or even declines in life expectancy, including the United States and the United Kingdom.
Could this indicate a broader decline in health progress in English-speaking countries?
Our new study compared life expectancy between English-speaking countries and other high-income countries.
We found that Australians born between 1930 and 1969 continue to have exceptionally good life expectancies. But the picture is not so rosy for those under 50: life expectancy is stagnating for this group of young people.
Why measure life expectancy?
Life expectancy is a valuable and widely used measure for examining health trends and patterns over time and comparing different locations or population groups.
It estimates the average number of years a person could live. This is calculated using mortality – or death rates – in different age groups over a specific period. When mortality rates decrease, life expectancy increases, and vice versa.
Not only does life expectancy tell us about mortality within a population, but it indirectly constitutes a measure of the overall health of the population. The leading causes of death in high-income countries are chronic diseases.
Stagnations or reversals in life expectancy can be warning signs of old or emerging health problems.
Nobel Prize-winning economist Amartya Sen also highlighted mortality as a key indicator of economic success and failure. This makes it a powerful tool for researchers and policy makers.
Thanks to a long, largely standardized tradition of collecting mortality statistics in high-income countries, researchers are able to conduct in-depth comparative studies.
This can help uncover how specific causes of death contributed to changes in life expectancy.
What we did
In our study, we analyzed mortality trends and patterns in a broader group of English-speaking countries and compared them to other high-income countries.
English-speaking countries have shown similarities in recent mortality trends and their causes, such as trends in drug overdose and obesity prevalence. Our analysis focuses on six high-income English-speaking countries: Australia, Canada, Ireland, New Zealand, the United Kingdom and the United States.
We compared them to the average of 14 other high-income, low-mortality Western European countries (such as France and Norway), as well as Japan. This was the “comparison group”.
We used data from 1970 onwards from comprehensive, well-established sources of high-quality mortality data: the Human Mortality Database and the World Health Organization Mortality Database.
For each English-speaking country and the comparison group, we estimated:
- life expectancy at birth
- partial life expectancy between 0 and 50 years
- remaining life expectancy at 50
- average lifespan.
Looking at average lifespan allows us to compare the mortality of birth cohorts (people born in the same calendar year) as they age.
This measure provides the closest way to estimate the actual lifespan of people in different populations and can be used to assess differences in survival between populations.
We first examined the extent to which age and causes of death contributed to the gap between English-speaking countries and the comparison group. We then compared the average lifespan of different birth cohorts.
What we found
In the pre-COVID-19 period, Australian men and women had higher life expectancy at birth than the non-English speaking comparison group (the average across these 14 countries).
This was also true for men in Ireland, New Zealand and Canada. In the UK and US, however, life expectancy at birth was lower for men than for women, compared to the non-English speaking group.
But the most striking result is the difference in mortality between those under 50 in English-speaking and non-English-speaking countries.
Relatively high mortality rates among those under 50 have lowered overall life expectancy at birth in every English-speaking country, including Australia. Suicides and deaths related to drugs or alcohol are the main reason for these trends.
But beyond the age of 50, Australia performs exceptionally well in terms of life expectancy for both men and women.
Australians born in the 1930s and 1960s are likely to live longer than those in the non-English-speaking comparison group and those in all other English-speaking countries.
But Australians born in the 1970s had lower life expectancies than the comparison group.
This means that overall, life expectancy at birth in Australia is higher than the average for the non-English group. But when broken down by age, the results show a clear distinction in life expectancy by date of birth.
For example, between 2017 and 2019, life expectancy for men aged 0 to 50 was 0.3 years lower in Australia than the average for the non-English group, while life expectancy remained at 50 years was 1.45 years higher.
What does this mean
Our study shows a worrying trend for people born from the 1970s onwards. This is true in all English-speaking countries, even before taking into account the negative impacts of the COVID-19 pandemic in countries like the United Kingdom and the United States.
In Australia, the results highlight significant generational differences in life expectancy compared to other high-income countries.
If the relatively high mortality rates of Australians born from the 1970s onwards continue, gains in life expectancy in Australia will likely slow.
Our status as having will decrease.
Our research aimed to examine trends and potential causes of stagnating life expectancy, rather than make policy recommendations.
But the findings suggest that real improvements could come from measures reducing inequalities and structural disadvantages that lead to poor health outcomes, such as improving access to education and job security. employment and housing, support for mental health and drug safety, and the fight against drugs.
Sergey Timonin is a demography researcher at the School of Demography at the Australian National University. Tim Adair is a Senior Research Fellow at the Melbourne School of Population and Global Health, University of Melbourne.
