Vulnerability to heatwaves: a scoping review of prevention programs. Results from the ENBEL project

BACKGROUND: This study, conducted as part of the European ENBEL project (Horizon 2020), aims at synthesising the scientific evidence on heat health preventive measures targeting vulnerable populations, considering other environmental co-exposures, such as air pollution, wildfires and droughts. METHODS: A scoping review was performed on Medline and Embase (Ovid) through search terms on clinical and social vulnerabilities, health outcomes (morbidity, mortality, hospitalisation), heatwaves, droughts, air pollution, wildfires, and preventive measures. Records in English published between 2000 and 2023 were included and screened according to PRISMA guidelines. RESULTS: 8608 records were retrieved, 5895 of which screened after duplicate removal. 51 were included in the qualitative synthesis. The interventions, mainly targeting workers (from agriculture, healthcare, waste management, firefighting and military sectors) and school athletes, were the most evaluated preventive measures. The role of hydration, rest in the shade, cooling cloths and food, and acclimatisation procedures were highlighted for both groups. On the other hand, local prevention plans, mainly from high-income Countries, focused on the elderly, adults in poor health conditions, homeless and institutionalised people. The implemented measures concentrate on cooling interventions, provision of health care and social services, education and information campaigns. Regarding co-exposures, a study on prevention for firefighters and one on the implementation of Clean Air Centres in California for people vulnerable to heat and smoke were retrieved. A search of the grey literature will be performed to avoid publication bias. CONCLUSIONS: There is still limited evidence on the effectiveness of preventive measures aimed at protecting vulnerable subgroups from heat-related health effects. The present findings can help orient the public health agenda and research priorities on climate changes adaptation measures. KEY MESSAGES: • Heatwaves are more frequent due to climate change, putting vulnerable population at risk. Developing plans and programs aimed at reducing negative health outcomes related to heat should be a priority. • Hydration, rest, and acclimatization procedures reduce heat-related illnesses in workers and athletes. Local prevention plans for the elderly show the role of education and information.