The number of people impacted by cardiovascular disease caused by hot weather is expected to double by the middle of the century if current climate trends continue, according to new research from the University of Adelaide.
Using data from the Australian Burden of Disease Database (ABDD), Professor Peng Bi, from the University's School of Public Health, and team found an average of 49,483 years of healthy life were lost annually in Australia to cardiovascular disease caused by hot weather.
Most of the years lost were due to an increase in deaths caused by cardiovascular disease rather than an increase in people developing the disease.
Published in the European Heart Journal, the findings were made by using the ABDD's disability-adjusted life years (DALYs) figures from 2003 to 2018.
The team used these figures to develop a statistical model to calculate how much cardiovascular disease can be attributed to hot weather in different parts of Australia and the whole country.
About 7.3 per cent of the total burden due to illness and death from cardiovascular disease is caused by the extreme conditions, and Professor Bi suggests that number could double or even triple by 2050.
"When the weather is hot, our hearts must work harder to help us cool down. This added pressure can be dangerous, especially for people with cardiovascular disease," said Professor Bi.
"Although our study is focused on Australia, the fundamental link between higher temperatures and increased cardiovascular risk has been documented globally."
The researchers also used their model to look at the likely impact of increased temperatures caused by climate change. They used two climate change scenarios outlined by the Intergovernmental Panel on Climate Change: one in which emissions stabilise and another in which they continually rise.
In the first projected scenario, the number of DALYs lost due to cardiovascular disease caused by hot weather would reach 90,779 by 2030 and 139,828 by 2050. Under the more severe second scenario, the DALYs are projected to increase to 95,343 in 2030 and to 161,095 in 2050.
"This study combines several key factors - climate change, population shifts, and adaptation scenarios - to give a full picture of the disease burden across Australia. This makes our study one of the first of its kind globally," said lead author Dr Jingwen Liu from the University's School of Public Health.
"Our models rely on assumptions that may not capture every real-life detail; however, despite these uncertainties, our comprehensive approach makes the study valuable for planning future climate change adaptation and mitigation strategies."
The model also shows that it would be possible to drastically lower the impact of high temperatures on cardiovascular disease with strategies that help people adapt to hotter weather.
"Our findings also call for urgent investment in adaptation and mitigation strategies, including urban cooling plans, public health campaigns and improved emergency responses during hot weather," said Professor Bi.
