The impacts of extreme weather events on health services and systems: A systematic review of reviews

OBJECTIVES: Beyond health impacts, Extreme Weather Events (EWEs) disrupt health services and systems, an aspect often overlooked in favour of individual health outcomes. This systematic review of reviews aimed to systematically map the diverse impacts of EWEs on health services and systems, offering essential information to enhance disaster preparedness across different healthcare delivery settings. STUDY DESIGN: A systematic review of reviews was chosen as the best method to achieve the study objective, following PRISMA guidelines for conduct and reporting. METHODS: PubMed, Scopus, and Web of Science were searched for narrative or systematic reviews, with or without a meta-analysis, published in the past 10 years. We evaluated the impact of floods, storms, heatwaves, cold spells, and wildfires on different components, from pre-hospital care to primary care and pharmacies. Results were thematically analysed to categorise impacts by hazard type, affected component, and impact type. RESULTS: A total of 114 reviews were included, detailing EWEs' consequences on health services and systems, and showcasing the heterogeneity of impacts across different healthcare delivery settings and hazard types. Floods and storms disrupt hospital and pre-hospital services through infrastructure damage and road closures. Heatwaves increase ambulance dispatches, emergency department visits, hospitalisations, and primary care use, due to heat exposure and chronic disease exacerbation. Increased particulate matter levels during wildfires was also associated with increased healthcare use. CONCLUSIONS: These findings highlight the significant impact of EWEs on health services and systems, and underscore the need for appropriate adaptation measures. They offer practical evidence to enhance health system preparedness and reduce the impact of EWEs.