As the climate change make them heat More and more frequent, there are also concerns about the neurological effects of extreme heat.
In extensive article of BBCexperts describe how the human brain – an organ extremely sensitive to temperature – already suffers and things can worsen as the heatwaves become more intense due to climate change.
The story of Jake, a British boy with Dravet syndrome, is characteristic. At just five months, he presented his first epileptic seizure during the heat. Since then, every summer is accompanied by new episodes. Today, at the age of 13, he lives with a neurological condition that is exacerbated by the heat.
Professor Sanjay Sisodiya, a neurologist at University College London, explains that this is merely one of the many diseases that get worse with rising temperatures: epilepsy, stroke, multiple sclerosis, migraines and others. Only in the 2003 heatwave in Europe, about 7% of deaths were related to neurological complications. Corresponding data was also recorded in 2022 in Britain.
The brain does not withstand the heat
Even healthy brains are affected: insomnia, depression, aggression and reduced concentration are common in heatwave. The brain produces its own heat, which must be constantly eliminated through blood circulation – a function disturbed when the body is overheated.
In people with neurological disorders, the problem is more intense: some diseases prevent sweating or altering thermoregulation. Also, drugs such as schizophrenia make the body more vulnerable to heat stroke and sudden death due to heat.
Elderly with dementia are particularly at risk: on the one hand they regulate their temperature more difficult, on the other they may forget to hydrate or avoid exposure to the sun. Hospitals and deaths increase dramatically in each wave of heat.
Everyone is in danger – from pregnant to financially weak
A study in 25 countries showed that two additional deaths per 1,000 are added to the hottest days of ischemic strokes. On a global scale, this means over 10,000 additional deaths a year. The poorest countries are disproportionately affected.
The heat also affects pregnancy: According to Imperial College London Jane Hirst, heat exposure is associated with an increase of 26% in premature births – which can cause neurodevelopmental problems.
High temperature also weakens the blood -brain barrier, leaving toxins, viruses and bacteria to enter the brain. By expanding mosquitoes due to climate, viruses such as Zika or Dangelic fever may spread more.
We do not yet know if the greatest threat is the maximum temperature, the heat of the heat or the hot nights. Not even because some people can withstand the heat better. They may also play a role in genetic factors, as Sisodiya estimates.
“What we see today in people with neurological diseases, maybe tomorrow concerns the general population,” he warns.
The planet is burning. And the era of the “boiled brain” has just begun.