News release

From:

As record-breaking heat grips communities worldwide and Australia prepares for an intense El Niño summer, new research provides the first global review linking high temperatures and heatwaves to poorer mental health in children and young people.

Published in the International Journal of Epidemiology, the findings show that adverse mental health outcomes increase by almost 1% for children with every 1 °C rise in daily temperature.

Drawing on data from 23 global studies examining the relationship between temperature, heatwaves, and mental health, the review found children aged 5 to 18 years are the most vulnerable. Their risk of poor mental health outcomes increases by 25% during heatwaves and by 1.5% in higher temperatures.

Flinders University epidemiologist, Associate Professor Jacqueline Stephens, a co-author of the study, says climate is driving more frequent and severe high temperatures and heatwaves in Australia and around the world, posing increasing public health risks, particularly for children and young people.

“There’s a range of reasons why children are more susceptible to changes in climate that are linked to social and developmental stressors, including disruptions to outdoor activities, their education, and recreational opportunities,” says Associate Professor Stephens from the College of Medicine and Public Health.

“The impacts can include sleep disruption during hot nights, which can affect wellbeing and emotional regulation, as well as indirect effects to parents’ mental health, caregiving stress, and family conflict, all of which increase during heatwaves and extreme weather events that are becoming more common.

“Adolescence is also a sensitive period for mental health development, which can increase susceptibility to extreme heat. Higher temperatures have also been associated with poorer learning and academic performance in children.”

Co-author, Matthew Flinders Professor of Global Ecology Corey Bradshaw from Flinders University, says the findings support the need to integrate mental health into climate-adaptation efforts and to develop targeted interventions for children and young people.

“Our modelling shows high temperatures and heatwaves lead to increased emergency visits, anxiety and depression, and suicide attempts, so targeted intervention strategies at scale need to be introduced in countries like Australia where severe weather is becoming commonplace”, says Professor Bradshaw from the College of Science and Engineering.

“Children and young people are especially vulnerable because of their physiological and behavioural susceptibility to heat, because they’re still developing and have a lower likelihood of adopting protective behaviours during extreme heat events.

“Our review also found that risks were higher in developed countries, potentially reflecting the effects of urban heat islands as well as greater support seeking to combat the impact on young people’s mental health.”

By contrast, the weaker impacts of heat in middle-income countries could be due to under-reporting rather than lower vulnerability within the population, according to the authors.

Co-author, Dr Syeda Hira Fatima, from the HEAL Global Research Centre at the University of Canberra and affiliated with Flinders University, says the findings highlight the need to move beyond understanding the risks of extreme heat and consider how children and young people can be better protected as temperatures rise.

“These findings highlight the need to think beyond the immediate physical health effects of extreme heat and consider how children’s mental health and wellbeing can also be protected,” says Dr Fatima.

“In Australia, an important next step is to better understand where and how children are exposed to heat in their everyday environments and develop practical, child-focused responses.

“This could include adaptations such as cooler classrooms, better ventilation and shaded outdoor spaces, alongside research to determine whether these measures translate into meaningful improvements in children’s mental health and wellbeing.”

The authors acknowledge evidence for heatwave-related mental health outcomes should be interpreted cautiously until more evidence is available.

The research – ‘First global synthesis of heat-related mental health impacts in children and young people: a systematic review and meta-analysis’, by Shevonne Kwan, Jacqueline Stephens, Corey J.A. Bradshaw, Blesson M. Varghese, Kirrilly Thompson, Melinda A. Judge, Peter N. Le Souëf and Syeda H. Fatima – has been published in International Journal of Epidemiology DOI: 10.1093/ije/dyag121