Public health effectiveness of cooling centres during periods of adverse hot weather: a systematic literature review

Abstract Human-induced climate change has led to hotter, longer, and more severe heatwaves globally. In high-income settings, cooling centres are increasingly used as public health interventions to mitigate heat-related impacts. This review evaluates the evidence of the effect of publicly accessible indoor cooling centres in the Organization for Economic Co-operation and Development (OECD) member countries on heat-related morbidity and mortality. A systematic review was conducted using MEDLINE, Embase, Web of Science, CENTRAL, and Google Scholar for studies from OECD countries published between 1 January 2010 and 30 April 2024. Records were screened for inclusion based on titles, abstracts, and full texts by two independent reviewers. Quality was assessed using the Mixed Methods Appraisal Tool. From 3,718 unique records, five studies met inclusion criteria. An ecological study linked access to cool spaces, including commercial areas, with reduced heat-related ill health. A modelling study indicated many cooling centre visits are needed to prevent one heat-related death or hospitalization; a finding contested by a similar study focusing on vulnerable groups. Two simulated heatwave studies reported that cooling centres provided only transient physiological benefits to healthy older adults. No studies reported real-world health outcomes for cooling centre users. There is limited direct evidence for the impact of real-world cooling centres on heat-related health outcomes. Laboratory based studies suggest that the benefit to users is transient and small. Experimental research of real-world cooling centres is urgently needed to address the evidence gaps in heat response planning, given the worsening severity of heatwaves.