Understanding current and projected emergency department presentations and associated healthcare costs in a changing thermal climate in Adelaide, South Australia.

BACKGROUND: Exposure to extreme temperatures is associated with increased emergency department (ED) presentations. The resulting burden on health service costs and the potential impact of climate change is largely unknown. This study examines the temperature-EDs/cost relationships in Adelaide, South Australia and how this may be impacted by increasing temperatures. METHODS: A time series analysis using a distributed lag nonlinear model was used to explore the exposure-response relationships. The net-attributable, cold-attributable and heat-attributable ED presentations for temperature-related diseases and costs were calculated for the baseline (2014-2017) and future periods (2034-2037 and 2054-2057) under three climate representative concentration pathways (RCPs). RESULTS: The baseline heat-attributable ED presentations were estimated to be 3600 (95% empirical CI (eCI) 700 to 6500) with associated cost of $A4.7 million (95% eCI 1.8 to 7.5). Heat-attributable ED presentations and costs were projected to increase during 2030s and 2050s with no change in the cold-attributable burden. Under RCP8.5 and population growth, the increase in heat-attributable burden would be 1.9% (95% eCI 0.8% to 3.0%) for ED presentations and 2.5% (95% eCI 1.3% to 3.7%) for ED costs during 2030s. Under the same conditions, the heat effect is expected to increase by 3.7% (95% eCI 1.7% to 5.6%) for ED presentations and 5.0% (95% eCI 2.6% to 7.1%) for ED costs during 2050s. CONCLUSIONS: Projected climate change is likely to increase heat-attributable emergency presentations and the associated costs in Adelaide. Planning health service resources to meet these changes will be necessary as part of broader risk mitigation strategies and public health adaptation actions.

Evaluating cost benefits from a heat health warning system in Adelaide, South Australia.

OBJECTIVE: To examine the cost benefits of a heat health warning system (HHWS) in South Australia. METHODS: Information from key agencies was used to estimate the costs associated with the South Australian HHWS, including for three targeted public health interventions. Health cost savings were estimated based on previously reported HHWS-attributable reductions in hospital and emergency department (ED) admissions and ambulance callouts. RESULTS: The estimated cost for a one-week activation of the HHWS was AU$593,000. Activation costs compare favourably with the potential costs averted through HHWS-attributable reductions in hospital admissions and ambulance callouts with an estimated benefit-cost ratio of 2.0-3.3. CONCLUSIONS: On the basis of estimated cost benefit, the South Australian HHWS is a no-regret public health response to heatwaves. IMPLICATIONS FOR PUBLIC HEALTH: As global temperatures rise there are likely to be significant health impacts from more frequent and intense heatwaves. This study indicates that HHWSs incorporating targeted supports for vulnerable groups are likely to be cost-effective public health interventions.