The beginning of autumn hasn't cooled down Australia's persistent heat waves, as temperatures climbed up to 15 degrees higher than usual across southeastern states on Saturday.
It followed the hottest spring and summer ever documented, With average temperatures across the country rising above pre-industrial levels by over two degrees Celsius.
Currently, these intense heat events account for 7.3 percent of Australia's heart disease burden, as indicated by recent studies.
And should the present trajectory of greenhouse gas emissions persist, this number might doubled, or possibly tripled, by mid-century.
Effects of warmth on cardiac function
Heart disease stands as the primary reason for fatalities both worldwide and in Australia.
In 2023, ischaemic heart disease, which falls under the category of cardiovascular diseases, was responsible for 9.2 percent of fatalities. based on the statistics provided by the Australian Bureau of Statistics.
It was cited as the cause of over 35,000 fatalities.
A research paper authenticated by multiple Australian universities, published in the European Heart Journal It was discovered that the likelihood of developing heart disease rose as temperatures went up.
Over the span of 15 years, between 2003 and 2018, the research revealed that over 48,000 years of potential lifespan were lost annually because of heart conditions linked to high temperatures.
Many of those years were squandered because of death, not sickness.
Peng Bi, a professor specializing in public health and environmental medicine at the University of Adelaide, highlighted how heat can put strain on the cardiovascular system.
He mentioned, 'When the temperatures rise, our hearts must work overtime to assist with cooling us off.'
Additional stress from this can pose risks, particularly for individuals with heart conditions.
The picture across Australia
To determine the present effect of elevated temperatures, the scientists analyzed information from the Australian Burden of Disease Database regarding illnesses or fatalities due to heart conditions between 2003 and 2018.
The research additionally explored the potential changes in the impact of cardiovascular diseases as projected under various future climatic conditions.
It depicted differing effects throughout the nation, influenced by factors such as population increase, demographic shifts, and how Australians respond to higher temperatures.
Professor Bi stated that this research integrates various crucial elements such as climate change, demographic changes, and adaptation measures to provide a comprehensive view of the health impact across Australia.
In South Australia, the incidence of cardiovascular diseases linked to high temperatures was the highest, with Victoria coming in second.
According to the research, the southern areas experienced greater relative risks along with lower levels of adaptation to high temperatures.
By the 2030s, South Australia is expected to maintain both the highest percentage and frequency of heat-related heart diseases compared to other regions due to increasing temperatures.
The Northern Territory experienced the smallest proportion of cardiovascular diseases linked to higher temperatures.
However, owing to its naturally temperate climate, the region is anticipated to experience the largest percentage rise in temperatures moving forward.
Based on the level of human adaptation, the Northern Territory was anticipated to experience the greatest increase in both the incidence and percentage of cardiovascular diseases linked to elevated temperatures by the 2050s.
The research highlighted that a significant portion of the Northern Territory’s populace faced socioeconomic and health issues, indicating that urgent action was required for climate change adaptation and mitigation measures.
Different future climate scenarios
The previous year marked the highest temperature ever recorded. based on data from the Copernicus Climate Change Service (C3CS)
In 2024, for the first time ever, the global temperature recorded in this calendar year surpassed pre-industrial levels by over 1.5 degrees Celsius.
Climate experts have linked the rise of temperatures by 1.5 degrees Celsius globally to an increased number of extremely hot days.
The research examined two distinct climate scenarios presented by the Intergovernmental Panel on Climate Change to forecast the potential increase in cardiovascular disease burdens due to climate change.
It utilized a metric known as Disability-Adjusted Life Years, which assesses the total number of healthy years lost due to either disease or mortality.
If emissions stabilize, the number of disability-adjusted life years lost because of heart disease might rise by 83.5 percent by 2030.
Should emissions keep increasing, this figure might soar by as much as 92.7 percent over the coming half-decade.
In a "worst-case scenario," there might be an increase of up to 182.6 percent by 2050.
[Graph: Temperature record]Adjusting to a warmer environment
The researchers said predicting future disease burden always came with some uncertainty.
Models rely on assumptions that might not capture every real-life detail.
However, the study showed that it would be possible to "drastically lower" the impact of high temperatures on cardiovascular disease with strategies that helped people adapt to hotter weather.
The research calls for urgent investment in adaptation and mitigation strategies, with tailored solutions for different jurisdictions in Australia.
These encompass city cooling initiatives, public health drives, and enhanced emergency reactions when temperatures soar.
"According to our findings, as climate change leads to more frequent and severe heatwaves, the dangers linked to increased temperatures are expected to rise, particularly affecting those who are most susceptible," stated Professor Bi.
This emphasizes the significance of being cautious in hot conditions by keeping hydrated, locating cooler spaces, and obtaining medical assistance whenever necessary.
The researchers contributing to this report included members from the University of Adelaide, The University of Sydney, the Australian Institute of Health and Welfare (AIHW), and Monash University.
And it was funded as part of an Australian Research Council Discovery Program project.
The researchers indicated that even though the study was centered on Australia, its insights apply to individuals globally.
