Center for Healthy Communities

Extreme heat can be highly detrimental to the brain health of older adults over long periods of time. Hyperthermia, a state of abnormally high body temperature caused in part by excessive exposure to heat, directly impairs one’s ability to complete tasks that involve complex cognitive functions and skilled motor performances. The culmination of pathological changes in the brain—particularly vascular damage—is neurodegeneration causing dementia, but it is unclear whether and how long periods of exposure to extreme heat leads to dementia. Household energy usage and sleep quality are potential mechanisms underlying the relationship between chronic exposure to extreme heat and brain health. Low electricity usage in areas that experience extreme heat may indicate heat-related energy insecurity; insufficient indoor air conditioning can magnify the extent to which populations are exposed to extreme heat and has been linked to excess mortality during heat waves. Furthermore, nighttime heat can lead to poor sleep quality, and sleep is integral to the glymphatic clearance pathway that supports memory and is key for brain health maintenance. A better understanding of these mechanisms can provide insight into community-level prevention measures for mitigating the impact of extreme heat on population brain health. The health burden presented by extreme heat-related dementia is especially relevant for Texas, which has experienced an increase in warming events in recent years and a large rural population that is socially and geographically vulnerable to poor health outcomes across the life-course. We will use mapping and statistical modeling to quantify the relationship between various definitions of extreme heat and dementia; and evaluate electricity usage and nighttime heat as potential mechanisms.