Exploring the Social, Psychological, and Behavioral Mechanisms of Heat Vulnerability in the City of Phoenix, AZ

Abstract

We tested mediation models using structural equation modeling (SEM) to better understand the pathways that lead to negative heat-health outcomes for socially vulnerable households and individuals in Phoenix, AZ. Extreme heat presents a significant risk to public health, and current theories of social vulnerability cannot explain the mechanistic pathways that lead to negative health outcomes. A better understanding of these pathways can be used to target more effective public health interventions. We find that self-reported indoor thermal discomfort was a strong and significant predictor of indoor heat illness outcomes (Std [Formula: see text], [Formula: see text]), suggesting that heat risk messaging could encourage the public to trust their personal sense of being too warm. Thermal discomfort (Std [Formula: see text], [Formula: see text]) and self-reported indoor heat illness (Std [Formula: see text], [Formula: see text]) were only predicted by socioeconomic status (SES); age, gender, and racialized group did not relate to heat illness or thermal discomfort based on our sample. However, specified mediators did not fully explain the relationship between SES and thermal discomfort or heat illness, suggesting that we do not fully understand how social vulnerability manifests as negative heat-health outcomes. In addition, results show that passive cooling techniques, like taking a cold shower, did not have a protective effect on heat-health outcomes, and these passive cooling behaviors were used in greater proportion by socially vulnerable individuals. This study concludes with 11 evidence-based hypotheses about how social vulnerability may produce negative heat-health outcomes.