Summer Heat, Historic Redlining, and Neighborhood Walking among Older Adults: 2017 National Household Travel Survey.

No known studies have examined the relationships between urban heat islands, historic redlining, and neighborhood walking in older adults. We assessed whether (1) individual and neighborhood characteristics (including redlining score) differ by neighborhood summer land surface temperature (LST); (2) higher LST is associated with less neighborhood walking, and whether associations differ by historic redlining score; and (3) neighborhoods with discriminatory redlining scores have greater LSTs. We used data on 3982 ≥ 65 years old from the 2017 National Household Travel Survey. Multivariable negative binomial and linear regressions tested associations between LST z-score (comparing participant's neighborhood LST to surrounding region's LST) and self-reported neighborhood walking and the association between living in neighborhoods redlined as "definitely declining" or "hazardous" (versus "still desirable"/"best") and LST z-score. LSTs were higher for those in neighborhoods with higher area deprivation scores and more African American/Black residents. Older adults living in neighborhoods with higher summer LST z-scores had fewer minutes of neighborhood walking/day. This association seemed limited to individuals with neighborhood redlining scores of "still desirable"/"best." Neighborhood redlining scores of "definitely declining" or "hazardous" (versus "still desirable" and "best") were associated with greater neighborhood summer LSTs. Overall, these findings suggest that historically redlined neighborhoods may experience urban heat island effects more often. While older adults living in hotter neighborhoods with "still desirable" or "best" redlining scores may less often engage in neighborhood walking, those in neighborhoods with redlining scores of "definitely declining" and "hazardous" do not seem to decrease neighborhood walking with higher LSTs. Future work is needed to elucidate the impact of extreme heat on health-promoting behaviors such as walking and the types of interventions that can successfully counteract negative impacts on historically disadvantaged communities.