Climate Change May Worsen Neurological and Mental Disorders, Study Finds

A new study highlights the alarming impact of anthropogenic climate change on neurological and psychiatric health. Researchers at University College London (UCL) have analyzed extensive neuroscience literature to reveal how extreme heat and climate change-fueled disasters exacerbate key neurological diseases and mental health disorders. This research underscores the urgency of addressing environmental factors that not only increase the prevalence of these conditions but also heighten the associated risks of hospital admissions, disabilities, and even death.

While the health impacts of climate change on infectious and respiratory diseases are well-documented, its effects on neurological health have been less studied. The body's temperature regulation process appears to play a significant role in the rise of conditions triggered by extreme heat. Professor Sanjay Sisodiya, who led the research at the UCL Queen Square Institute of Neurology, highlights that making interpretations about the effects of climate change on neurological and psychiatric diseases is challenging due to the overall sparsity of data, varying study methods, and a lack of detailed consideration of disease subtypes and individual genetics.

Despite these challenges, evidence suggests that the prevalence and severity of numerous nervous system conditions, such as strokes, neurological infections, and mental health disorders, are influenced by climate change. The data reveal broad and complex adverse effects, particularly from temperature extremes and wide diurnal temperature fluctuations. The lack of studies projecting the future consequences of climate change on brain health hinders policy advancements, despite the possibility of protective actions through local forecasting. It is vital to conduct thorough research on the risks posed by climate change to people who are susceptible to neurological illnesses.

Further investigation is required to understand the mechanisms linking neurological disorders with higher temperatures. As extreme weather worsens and becomes more frequent, it is increasingly vital to unravel this relationship, especially for the most vulnerable populations.

The study reviewed 332 reports on environmental impacts on 19 neurological conditions with the highest disease burdens, including Alzheimer’s, migraines, strokes, multiple sclerosis, and meningitis. It also included research on psychiatric disorders like depression, anxiety, and schizophrenia, which frequently co-occur with neurological diseases.

The findings indicate that weather impacts each disease in distinct ways, but most conditions are broadly associated with higher prevalence and worsened symptoms. For instance, individuals with Alzheimer’s and other dementias struggle to make adaptive choices in extreme heat, such as seeking assistance, wearing lighter clothing, and staying hydrated. Hotter weather is also likely to lead to more fatal or disabling strokes and can exacerbate epilepsy, particularly due to sleep deprivation. High nighttime temperatures, a hallmark of climate change, significantly impact sleep patterns. The study also found that extreme cold can adversely affect health.

The incidence of mental health disorders, along with hospitalization and risk of death, was most strongly associated with increased ambient temperatures. One report from the study indicated that US health insurance claims for mental health-related emergency room visits between 2010 and 2019 surged on days with extreme heat. Moreover, extreme weather events like storms and wildfires can trigger acute anxiety, post-traumatic stress, depression, and suicidal ideation.

Burcin Ikiz, a neuroscientist studying environmental patterns' impact on the brain, noted that the brain’s response to a warming climate causes damage that can go undetected until long after medical intervention would be effective.

Professor Sisodiya and Dr. Ikiz, the founder and chair of the International Neuro Climate Working Group, have called for increased research and policy intervention to mitigate the economic toll of climate change on individuals and public health systems, particularly in poorer countries.

As the world faces another round of record-breaking summer heat, individuals can also take steps to protect against extreme heat, ensuring better health outcomes in the face of climate challenges.