Hot Weather Threatens Those with Dementia

Heat can further impact the brains of those living with dementia.

While elderly people are generally more susceptible to heat-related illnesses, those with dementia may face particular risks during hot weather due to impaired perceptions, side affects associated with some medications, psychological distress and other factors. According to a 2022 NIH study in England, people with dementia were 4.5% more likely to be admitted to a hospital for every degree of temperature increase above 17 degrees Celsius (62.6 degrees Fahrenheit).

As the global climate continues to warm and people in the U.S. and around the world experience record-breaking heatwaves, experts are increasingly exploring what this means for our most vulnerable populations – including those with dementia.

“Extreme temperatures and heat are especially dangerous for people living with dementia-related illnesses because they are more susceptible to heat stroke, hyperthermia, and dehydration due to the way these illnesses impact the brain,” said Jennifer Reeder, Director of Educational and Social Services at the Alzheimer’s Foundation of America. “Caregivers need to be proactive and prepared to protect their loved ones.” The AFA recommends taking measures to prevent wandering, assisting with hydration, watching for signs of heat-related illness, and planning for places to cool down.

Experts recommend assisting those with dementia with hydration during hot weather.

Heat puts additional pressure on a brain already experiencing cognitive deficits. A study published in The Lancet Neurology in June 2024 found that high temperatures can limit communication between brain cells due to dehydration, psychological intolerance, and electrolyte losses. George Perry, a biology professor at the University of Texas at San Antonio, who was not affiliated with the study, clarified some reasons for this impact. “At high temperatures you have less oxygen being transported and [altering] metabolic processes to end up stressing a lot of different systems that keep the brain functioning normally,” Perry told Scientific American.

Additionally, hot weather could prompt aggressive or inappropriate behavior in individuals with dementia, or fail to trigger sensory responses altogether, boosting people’s exposure. As with individuals with mental illness , who are disproportionately affected by heat, those with dementia require additional monitoring and attention.