Indoor Heat Exposure Linked to Reduced Attention in Older Adults

Lab-based research has demonstrated a causal relationship between ambient heat and cognitive performance across different age groups. Meanwhile, many older adults often experience cognitive difficulties in their daily life. Yet, it remains unclear how real-world indoor heat exposure influences cognitive abilities in older adults within their own home, where they have at least partial control over the indoor temperature. We conducted a 12-month observational study of 47 community-dwelling older adults in Boston, MA. We continuously monitored participants’ home ambient temperature and sent them twice-daily surveys of self-reported attention difficulties. Overall, we collected 17,201 Ecological Momentary Assessments of attention that were time-synced with sensor-measured home ambient temperature at the time of response. Controlling for humidity and other relevant covariates, the odds ratio of experiencing difficulty keeping attention was lowest within the indoor temperature range of 20 - 24°C. Notably, a 4 °C increase beyond this range doubled (P<0.001) the likelihood of reporting difficulty maintaining attention. These results suggest that even among older adults who have air conditioning and a relatively high standard of living, temperature fluctuations can have detrimental impacts on cognitive well-being. Addressing indoor heat exposure is therefore crucial for protecting older adults’ cognitive functioning against the increase in frequency and intensity of heatwaves.