A new study from the University of Sydney has established a clear link between extreme heat and increased mental health hospital admissions among children and adolescents. As climate change drives more frequent and intense heatwaves across the globe, the findings underscore a growing public health challenge that European nations must confront.
Published in the journal The Lancet Planetary Health, the research analyzed over 1.2 million mental health hospital admissions in New South Wales, Australia, between 2001 and 2022. The data covered children up to 12 years old and adolescents aged 13 to 17. The authors found that admissions rose significantly during periods of unusually high temperatures, with the effect most pronounced during the colder months.
Mental Health Risks Amplified by Heat
The study identified a range of conditions exacerbated by extreme heat, including substance use disorders, depression, anxiety, obsessive-compulsive disorder, and behavioral disorders. Lead author Wen-Qiang He noted that “hotter-than-normal weather, which is becoming more frequent because of climate change, is already affecting the mental health of some of our most vulnerable young people.”
According to the World Health Organization, one in seven 10–19-year-olds worldwide experiences a mental disorder, accounting for 15% of the global disease burden in this age group. The new research suggests that climate change will worsen this burden, with heat-attributable admissions projected to rise by 6.0% to 7.7% under low or moderate greenhouse gas emissions scenarios by 2090–2099, and by 20.8% under a high emissions scenario.
Mechanisms and Indirect Effects
The study outlines several ways heat affects mental health. High temperatures impair the body’s ability to regulate internal temperature, disrupting cell function, increasing inflammation, and affecting blood pressure and brain cooling. These physiological changes can trigger mental stress, impair sleep, and contribute to irritability, aggression, and violence. Indirect effects include reduced sleep quality and decreased social interaction, both of which are critical for adolescent well-being.
While the exact reasons for the rise in hospital visits remain unclear, the researchers suggest that unexpected temperature changes may influence stress responses, sleep patterns, and mood. This is particularly relevant for Europe, where Southern and Central-Eastern Europe bear the brunt of extreme heatwaves, and where mental health services for young people are already under strain.
Implications for European Policy
European countries, from Spain to Poland, are experiencing more frequent and severe heatwaves. The study’s authors call for better prevention and adaptation strategies tailored to children and young people with mental health conditions. This includes integrating mental health considerations into climate adaptation plans, improving early warning systems, and ensuring that healthcare facilities are equipped to handle heat-related surges in demand.
In cities like Paris, Berlin, and Rome, urban heat islands can exacerbate the effects of extreme temperatures. The findings also resonate with broader health concerns, such as the need for stronger safeguards for children in digital environments, as both climate and technology pose emerging risks to youth mental health.
As the European Union pushes forward with its Green Deal and climate adaptation strategies, this research adds urgency to the call for targeted interventions. The study serves as a reminder that climate change is not just an environmental issue but a profound public health crisis, particularly for the continent’s youngest citizens.
