Periods of extreme heat, such as the summer of 2011, have proven to be dangerous for vulnerable older adults. This is particularly true for those who are socially isolated, who live in the upper floors of high-rise buildings, and those with chronic health conditions. A recently published study, based on data collected in Detroit during the summer of 2009, suggests that some potential adaptations to heat may be underused among older adults.
The researchers and study participants collected a daily log of responses to heat such as opening a window, using air conditioning, or going to a basement or porch. Participants were selected to include a range of residence types, including single-family homes and high-rise apartments. Each participant’s residence was set up with a temperature logger, which was installed away from windows, vents, or household heat sources. The researchers also tracked the outdoor temperature on an hourly basis. Finally, data was collected on environmental “imperviousness,” which is a measure of surrounding land surface that is covered by asphalt or concrete. These surfaces are impenetrable by water and have been shown to exacerbate the so-called “heat island” phenomenon, when urban areas with high imperviousness tend to develop higher surface temperatures. This data allowed the researchers to analyze the heat response behavior and analyze its association with in-home temperature, the reported area temperature (which would influence news and other media reports of heat danger), and environmental characteristics.
The article details the likelihood of each adaptive behavior at different temperature ranges. Surprisingly, the fewest adaptive behaviors occurred at indoor temperatures above 32.2°C (or 90°F); the authors suggest that this may have been caused by heat fatigue, yet this temperature range occurred less frequently than the other temperatures; as a result, the sample size may be too small to allow for interpretation of behaviors at this temperature. Participants in single-family homes were more likely to take a shower or change clothes in response to higher temperatures than those in other types of residence, while those living in high-rise buildings were more likely to use fans, air conditioning, or leave the house. Some behaviors, such as leaving the house, were more closely associated with the outdoor temperature than the indoor temperature, while opening windows or going to a basement were associated with indoor temperature but not outdoor temperature. The authors hypothesize that directly perceived temperatures might lead to more simple behaviors (like turning on a fan), while the perception of “heat danger” resulting from media reports of high temperatures may encourage more complex behaviors.
Overall, the researchers found that adaptive behaviors occurred at a relatively low rate, especially at very high temperatures, suggesting that older adults may be under-utilizing such strategies. The authors recommend that older adults be encouraged to engage in these and other adaptive behaviors such as increased fluid intake. These findings also reaffirm the need for communities to create emergency response plans for increased heat, including cooling locations and financial assistance for utility costs.
White-Newsome J.L.; Sánchez, B.N.; Parker, E.A.; Dvonch, J.T.; Zhang, Z.; and O’Neill M.S. (2011). “Assessing heat-adaptive behaviors among older, urban-dwelling adults.” Maturitas 70(1): 85-91.