Heat-Related Health Risks for People Experiencing Homelessness: A Rapid Review.

Extreme heat poses a significant public health threat for people experiencing homelessness (PEH), who face heightened risks due to prolonged outdoor exposure and limited access to resources. This rapid review synthesizes research from the past five years on the health impacts of extreme heat for PEH in high-income countries. A total of 11 studies were identified through a systematic search of multiple databases, focusing on publications from 2019 to 2024. The review highlights key vulnerability factors, including demographic characteristics, pre-existing health conditions, and geographic disparities, that increase heat-related health risks for PEH. Physical health impacts, such as heat-related morbidity and mortality, are common, alongside mental health and substance use disorders exacerbated by heat exposure. The review also highlights a significant increase in emergency department visits among PEH during heat events, emphasizing the additional burden on healthcare systems. Barriers, including limited physical and social access to cooling centers, water insecurity, and stigma, further compound these challenges. Addressing the unique vulnerabilities of PEH is crucial to reducing their risks during extreme heat events. Improving housing access and stability is essential as a long-term strategy to decrease homelessness and reduce heat stress in this vulnerable population. The review also underscores the need for inclusive interventions such as accessible cooling centers with targeted programming, regular access to water, and tailored healthcare services to meet the needs of PEH. Future research should focus on long-term studies to assess potential cumulative heat exposure effects and evaluate the effectiveness of interventions aimed at mitigating extreme heat impacts on PEH, while applying an intersectionality lens to explore how factors like race, gender, and age shape vulnerabilities and potential intervention strategies.