Determinant factors amplifying climate vulnerability and their effects on the health of homeless persons: A scoping review

Background: Climate change has led to adverse events such as heat waves and floods, disproportionately affecting vulnerable populations, including homeless persons. These populations face challenges such as lack of access to shelters and essential resources, increasing their exposure to climate-related risks and health issues. Aim: To map the determinant factors that amplify the climate vulnerability of homeless persons, analyzing their health impacts and the barriers to adaptation and resilience. Methods: A scoping review was conducted using the PCC framework (Population, Concept, Context). The search was performed in PubMed/MEDLINE, Web of Science, Embase, Scopus, Cochrane Library, and SciELO. Studies published in multiple languages were included, with no date restrictions. Results: A total of 3,046 studies were identified, of which 38 were selected for data extraction. The mapped determinant factors were grouped into five categories: extreme weather conditions, air quality and environmental inequality, infrastructure and access to services, social and economic impacts, and health aspects. The findings highlight how these vulnerabilities are exacerbated by climate events and suggest macro-, meso-, and micro-level interventions to mitigate their effects. Conclusion: The factors amplifying the climate vulnerability of homeless persons require an integrated approach encompassing public policies, infrastructure, and healthcare practices. Targeted actions can help reduce the negative impacts of climate change on this population.