Methods of Assessing Health Care Costs in a Changing Climate: A Case Study of Heatwaves and Ambulance Dispatches in Tasmania, Australia

Anthropogenic climate change is causing a rise in global temperatures, with this trend projected to increase into the future. Rising temperatures result in an increase in the frequency and severity of heatwave events, with an associated increase in poor health outcomes for vulnerable individuals. This places an increasing strain on health care services. However, methods calculating future health care costs associated with this trend are poorly understood. We calculated health care costs attributable to heatwave events in Tasmania 2009-2019, using ambulance dispatches as a case study. We also modeled the expected health and economic burden for projected heatwave frequencies between 2010 and 2089. We developed our models based on two possible approaches to describing population adaptation to heatwaves-an adapted population calculated by determining heatwave episodes using a rolling baseline, and a non-adapted population calculated by determining heatwave episodes using a static baseline. Using a rolling baseline calculation for 2010 to 2089, we estimated additional ambulance costs averaging AUD$57,147 per year and totaling AUD$4,571,788. For the same period using a static baseline, we estimated additional ambulance costs averaging AUD$517,342 per year and totaling AUD$41,387,349. While this method is suitable for estimating the health care costs associated with heatwaves, it could be utilized for estimating health care costs related to other climate-related extreme events. Different methods of estimating heatwaves, modeling an adapted versus non-adapted population, provide substantial differences in projected costs. There is potential for considerable health system cost savings when a population is supported to adapt to extreme heat. Our research describes the projected economic cost of heatwaves on health care services, using ambulance dispatches in Tasmania, Australia as a case study. We find that costs modeled for a population not adapted to heatwaves are almost 10 times higher than for a population adapted to heatwaves. Climate change related extreme events place pressure on health care systems, however future health care costs are poorly understoodWe calculate future costs related to heatwaves, using ambulance dispatches in Tasmania, Australia as a case studyProjected costs modeled for a non-adapted population are almost 10x higher than for an adapted population

Automated summary

Anthropogenic climate change is causing a rise in global temperatures, resulting in an increase in heatwave events and negative health outcomes. This study calculates the health care costs associated with heatwaves in Tasmania and models the economic burden for projected frequencies. It finds that a population adapted to heatwaves has significantly lower costs compared to a non-adapted population. These findings highlight the importance of population adaptation to extreme heat and the need for further understanding of future health care costs related to climate change.