As 2024 ends and is set to be the hottest year on record, surpassing the previous record set in 2023, researchers from UCLA Health in the US have warned of the impact of heat waves on patients with neurodegenerative disorders. In a statement published in JAMA Neurology, the researchers noted that these patients are at greater risk from extreme heat waves due to their increased risk of heat-related health complications.
The impact of heat waves on patients with neurodegenerative disorders: A danger that cannot be ignored
With global temperatures rising (global warming or global warming), Dr. Indu Subramanian said that doctors have a responsibility to increase awareness among patients with conditions such as dementia or Parkinson’s disease about the effects of heat on their health, and to develop preventive strategies to protect them. She added: “We have shown in our statement that heat-related deaths are preventable, and that physician intervention can make a big difference in this context.”
Extreme heat waves pose a health risk to anyone exposed to them, but their effects are more severe for people with neurodegenerative diseases because of the symptoms associated with these diseases or the medications used to treat them, which increases the risk of serious health complications.
Heat can worsen the symptoms of these diseases. For example, people with Parkinson’s disease suffer from symptoms - such as autonomic nervous system dysfunction - that can lead to an increased risk of dehydration, heat stroke (sunstroke), and fainting due to decreased blood flow to the brain. Other symptoms can lead to impaired sweating, which makes symptoms worse, especially in areas with high humidity.
Worsening symptoms can impair patients’ ability to perform normal daily activities such as taking medications, turning on air conditioning, rehydrating, or taking cold showers to stay cool. Also, some medications used to treat these conditions, such as anticholinergics and tricyclic antidepressants, can impair some body functions such as sweating and blood flow to the skin, which are essential functions for the body to cool itself naturally.
Previous studies show the impact of heatwaves on patients with neurodegenerative disorders
A 2020 study by the University of Malta (UM) found that mortality and hospital admissions for Parkinson’s disease increased by more than 10% when temperatures rose by just 1 degree Celsius above 33.9 degrees Celsius (93 degrees Fahrenheit). Another study by Queensland University of Technology (QUT) in 2019 found similar results in Alzheimer’s patients.
The study pointed to the role of green spaces in reducing heat-related deaths, as these spaces can reduce the heat island effect (areas that are relatively hotter than surrounding areas due to human activities) by providing shade, humidity and changing the path of radiation. It also found that people living in areas with less green space are three times more likely to die from heat-related deaths.
Proactive steps to address the impact of heat waves on patients with neurodegenerative disorders
As the U.S. population ages, so does the number of people with neurodegenerative diseases, such as dementia. The ability to maintain body temperature (thermoregulation) is often impaired in older adults. Heat-related complications are more common in men, and increased social isolation among older adults can increase the risk of heat-related problems because they are not detected early.
Dr. Subramanian was surprised by how many patients see doctors or healthcare providers as their only means of communicating with the world outside their homes, and noted that people with Parkinson’s disease and dementia are at increased risk of death during heat waves, but that proactive steps can be taken to protect them.
To address these challenges, Dr. Subramanian emphasized the need to develop medical guidelines and best practice guidelines for healthcare providers and medical institutions, and link them to quality standards and healthcare reimbursements. Examples include:
Conducting periodic screenings for social isolation in patients with neurodegenerative diseases and providing them with the necessary medical services and resources.
Providing telehealth care to high-risk patients, communicating with them and following up with them during periods of high temperatures.
Providing patients with guidebooks containing tips and useful resources for dealing with heat.