Climate change is exacerbating the symptoms of various brain conditions, according to a new review. Conditions such as stroke, migraines, meningitis, epilepsy, multiple sclerosis, schizophrenia, Alzheimer’s disease, and Parkinson’s disease are particularly vulnerable to rising temperatures and humidity levels.
Our brains are designed to manage environmental challenges, including temperature and humidity changes. Neurons in the brain, which function like learning, adapting computers, are sensitive to temperature variations and operate optimally within a narrow temperature range. However, climate change is pushing environmental conditions beyond these ranges, causing the brain’s temperature regulation mechanisms to falter.
Human bodies are generally comfortable between 20˚C to 26˚C with 20% to 80% humidity. However, many brain components are already working near their upper temperature limits. Rapid shifts into unaccustomed temperature ranges, due to extreme weather linked to climate change, disrupt the brain’s ability to regulate temperature, leading to malfunctions.
Certain neurological and psychiatric conditions complicate this problem further. For example, some diseases disrupt perspiration, essential for cooling, or impair the awareness of overheating. Medications for these conditions can also hinder the body’s temperature-regulating abilities. Heatwaves exacerbate these issues, disturbing sleep and worsening conditions like epilepsy. The faulty brain wiring in multiple sclerosis patients functions even less effectively in the heat, and higher temperatures can lead to dehydration, making blood thicker and more prone to clotting, which increases stroke risk.
Climate change’s impact on neurological diseases is significant. Rising temperatures correlate with increased hospital admissions for dementia, deteriorated seizure control in epilepsy, worsened symptoms in multiple sclerosis, and a higher incidence of strokes. Psychiatric conditions, such as schizophrenia, also see worsened symptoms and increased hospital admissions during heatwaves.
The 2003 European heatwave saw around 20% of excess deaths among people with neurological conditions. Extreme local temperature variations, larger-than-usual daily temperature fluctuations, and adverse weather events like heatwaves, storms, and floods can all worsen neurological conditions. Urban environments and lack of green spaces amplify these effects, particularly during heatwaves.
Globally, the number of people affected by neurological and psychiatric conditions that climate change could worsen is vast. Approximately 60 million people have epilepsy, and 55 million have dementia worldwide, with over 60% living in low- and middle-income countries. These numbers are expected to rise to over 150 million by 2050 as the population ages. Stroke remains the second-leading cause of death and a major cause of disability globally.
Addressing the Challenge
Addressing climate change requires comprehensive mitigation efforts led by governments and international coordination. However, significant changes will take years to manifest. In the interim, tailored information about the risks of extreme weather and temperature fluctuations should be provided to those with neurological diseases. Public health experts can educate on risk reduction strategies, and local weather-health alert systems should be adapted to cater to neurological conditions.
Collaborating with affected individuals, their families, and caregivers is crucial to ensure that weather-health alerts are practical and actionable. Without incorporating climate change considerations into neurological care, the benefits of scientific advancements could be undermined. Moreover, studying the impact of climate change on neurological diseases can provide insights into the potential effects on healthy brains pushed beyond their evolutionary boundaries.
As climate change continues to pose a threat, it is essential to address its impacts on brain health proactively. This includes advocating for action against climate change to maintain our cognitive health and well-being.