An analysis of international longevity data published in the open access journal BMJ opened finds that Australians outlive their peers in five high-income English-speaking countries, including the UK and the US, by 1 to 4 years.

The greatest benefit occurs between the ages of 45 and 84, as death rates from drug and alcohol abuse, preventable or treatable cancers, and cardiovascular and respiratory diseases are all lower, the analysis shows.

While high-income countries achieved good increases in life expectancy in the 20th century, researchers find that trends in the 21st century, even before the Covid-19 pandemic, were far less favorable.

Study: Life expectancy and geographic differences in mortality: a comparative observational study in six high-income English-speaking countries. Image credit: CandyRetriever / Shutterstock

They say the stagnant decline in deaths from cardiovascular disease and the rising number of deaths from drug overdoses, mental illness and neurological diseases are the main contributing factors. And the significant differences in life expectancy between the richest and the poorest that exist in most of these countries have widened in recent decades.

While high-income English-speaking countries have much in common, there are also significant differences, including inequalities in health and social systems, racial and ethnic composition, and immigration history.

The researchers therefore wanted to find out whether there are differences in life expectancy between Australia, Canada, Ireland, New Zealand, the UK and the USA, which are among the wealthiest economies in the world.

They obtained national life tables from the Human Mortality Database (HMD) for men and women in these countries and – for illustrative purposes only – for Austria, Belgium, Denmark, Finland, France, Germany, Italy, Japan, the Netherlands, Norway, Portugal, Spain, Sweden and Switzerland between 1990 and 2019.

The World Health Organization mortality database for all six English-speaking countries contained detailed information on deaths by sex, age and cause of death.

Data analysis found that Australia has led the world in average life expectancy at birth since the early 1990s, and in 2018 it was 1.26–3.95 years ahead of its peer countries for women and 0.97–4.88 years ahead of its peer countries for men.

Specifically, Australia has a life expectancy advantage of four to five years over the United States and a lead of one to two and a half years over Canada, New Zealand, Ireland and the United Kingdom.

Canada had the second highest life expectancy between 1990 and 2019. Most recently, Ireland and New Zealand caught up with Canada.

However, the US has performed worst every year since 2001. Over the last decade, the UK has generally had the second lowest life expectancy.

Similar trends can be observed in life expectancy at age 65, where Australia generally performs best and the United States performs worst, although the United States’ worst performance in life expectancy at age 65 has only become apparent more recently.

The differences in life expectancy at birth between the best and worst performers widened over time. In 1990, Canadian men and women had the highest life expectancies—74 and 80 years, respectively—while American men and Irish women had the lowest life expectancies—71 and 77 years, respectively.

The corresponding differences were 2.38 and 2.91 years, respectively. By 2019, these differences between Australia and the United States had doubled to 4.75 years for men and by 30% to 3.80 years for women.

While women in English-speaking countries were not among the leaders in female life expectancy in any of the 20 high-income countries between 1990 and 2019, men – with the exception of the United States – have typically ranked in the top half over the past decade.

Of all these countries, Australian men consistently ranked in the top four between 1990 and 2019, with one exception. However, American men have had the lowest life expectancy since 2005.

The 65-84 age group typically accounts for the largest share of the differences in life expectancy between Australia and the other five high-income English-speaking countries, ranging from 39% in the US to 78% in Ireland for women, and from 30% in the US to 100% in Ireland for men.

Although Australians have lower mortality rates in almost all age groups, the greatest advantage in life expectancy occurs between the ages of 45 and 84.

Ischemic heart disease, other circulatory diseases, cancer, respiratory diseases, mental illnesses and neurological diseases, especially Alzheimer’s disease and related dementias, are the main causes of differences in life expectancy in this age group.

However, Australia also has lower death rates from external causes, including drug and alcohol use, preventable or treatable cancers, cardiovascular disease and influenza/pneumonia.

In terms of life expectancy within individual countries, Canada and the United States perform the worst. Thirteen US states are in the lowest category for both men and women. In contrast, in the United Kingdom and Ireland, life expectancy in all regions is above 81 years for women and 76.5 years for men.

For both men and women, Australia has the lowest levels of inequality within a country, particularly for those over 40, followed by Canada. For women, inequality tends to be highest in New Zealand, Ireland and the US; for men, it is highest in New Zealand, the UK and the US.

The researchers acknowledge that they were unable to account for differences within local neighborhoods and that there may be differences in the coding of causes of death, particularly at older ages where multiple conditions may be present.

They cite several possible explanations for Australia’s top spot, including the country’s high proportion of overseas-born people – nearly 30% in 2018.

Another reason could be the low smoking rate. At the same time, public health initiatives related to gun ownership and mental health, as well as the highly rated health system, could also explain Australia’s top position in the life expectancy rankings.

“Australia is performing well but still has room for improvement, particularly in reducing inequalities among Indigenous people” and obesity rates, the researchers say. However, they conclude: “Overall, Australia offers a potential model for poorer-performing English-speaking countries such as the US and UK to reduce both premature mortality and inequalities in life expectancy.”