Carlos SolisProfessor of Neurology Sanjay Sisodia from University College London, a pioneer in studying the effects of climate change on the brain, often hears from his patients that they feel worse during .
After analyzing his own observations and the results of numerous studies, he identified a range of neurological disorders that worsen with rising temperatures and humidity. These include epilepsy, , encephalitis, multiple sclerosis, migraines, and more. The professor also found that the impact of on our brains is becoming increasingly evident, as reported by BBC.
For instance, during the European heatwave of 2003, about 7 percent of excess deaths were linked to neurological issues. Similar trends were observed during the heatwave in the UK in 2022.
However, extreme temperatures can also affect other brain functions, making us more aggressive, irritable, and depressed.
Like a Clock with All Its Mechanisms Out of Whack
of the human brain rarely exceeds the average body temperature by more than 1°C. However, the brain—one of the most energy-demanding organs in our body—produces a significant amount of its own heat when we think, remember, and respond to the world around us. This means our bodies have to exert considerable effort to keep the brain cool.
This is crucial because its cells are extremely sensitive to heat. It is believed that the function of certain molecules that transmit signals between cells also depends on temperature. In other words, they stop working effectively if the brain gets too hot or too cold.
According to Professor Sisodia, such a brain resembles a clock where all the mechanisms have “stopped functioning properly.”
In some neurological disorders, sweating can be disrupted. “Thermoregulation is a function of the brain, and it can be impaired if certain areas are not functioning correctly,” the scientist noted. He explained that some forms of multiple sclerosis can cause changes in body temperature. Additionally, certain medications for neurological and psychiatric disorders affect thermoregulation, making patients more vulnerable to heatstroke.
Extreme heat, especially elevated nighttime temperatures, can impact and mood. It leads to increased hospitalizations and mortality among individuals with .
Older adults struggle more to adapt to extreme heat. For example, they may not drink enough fluids, forget to close windows, or go outside when it’s unsafe.
High Risk of Strokes
Rising temperatures are also linked to an increase in the number of strokes and related mortality. Researchers analyzing stroke mortality data in 25 countries found that for every 1,000 deaths from ischemic stroke on the hottest days, there are two additional deaths.
“However, considering that seven million people die from strokes worldwide each year, heat could be responsible for more than 10,000 additional stroke deaths annually,” noted Bethan Davis, a stroke expert at Sussex University Hospital (UK).
Premature Births
“There is a connection between extreme heat and adverse pregnancy outcomes, such as premature births,” said Jane Hurst, a professor of global women’s health at Imperial College London. A recent systematic review of scientific studies showed that periods of extreme heat are associated with a 26 percent increase in the number of premature births.
Threat of Neurodegenerative Diseases
Excessive heat places additional stress on the , making it more vulnerable to damage that leads to neurodegenerative diseases. Abnormal heat also weakens the blood-brain barrier, which typically protects the brain, making it more permeable to toxins, bacteria, and viruses.
Heatwaves can affect a range of factors: the electrical activity of nerve cells, the risk of suicide, climate-related anxiety, and even the stability of medications for neurological disorders.
Heat affects people differently: some feel great during it, while others find it unbearable. “This differential sensitivity is influenced by various factors, one of which may be genetic predisposition,” said Professor Sisodia. Genetic variations can affect protein structures, making some individuals more susceptible to the consequences of climate change.
Photo: pixabay.com
