Emergency Department Visits and Ambient Temperature: Evaluating the Connection and Projecting Future Outcomes

Association between summertime emergency department visits and maximum daily heat index in rural and non-rural areas of Virginia (2015-2022)

There is growing evidence that high ambient temperatures are associated with a range of adverse health outcomes. Further evidence suggests differences in rural versus non-rural populations' vulnerability to heat-related adverse health outcomes. The current project aims to 1) refine estimated associations between maximum daily heat index (HI) and emergency department (ED) visits in regions of Virginia, and 2) compare associations between maximum daily HI and ED visits in rural versus non-rural areas of Virginia and within those areas, for persons 65 years of age and older versus those younger than 65 years. Our study utilized 16,873,213 healthcare visits from Virginia facilities reporting to the Virginia Department of Health syndromic surveillance system between May and September 2015-2022. Federal Office of Rural Health Policy defined rural areas were assigned to patient home ZIP code. The estimated daily maximum HI at which ED visits begin to rise varies between 25 °C and 33 °C across climate zones and regions of Virginia. Across all regions, estimated ED visits attributable to days with maximum HI above 25.7 °C were higher in rural areas (3.7%, 95% CI: 3.5%, 3.9%) versus in non-rural areas (3.1%, 95% CIs: 3.0%, 3.2%). Patients aged 0-64 years had a higher estimated heat attributable fraction of ED visits (4.2%, 95% CI: 4.0%, 4.3%) than patients 65 years and older (3.1%, 95% CI: 2.9%, 3.4%). Rural patients older than 65 have a higher estimated fraction of heat attributable ED visits (2.7%, 95% CI: 2.2%, 3.1%) compared to non-rural patients 65 years and older (1.5%, 95% CI: 1.3%, 1.8%). State-level syndromic surveillance data can be used to optimize heat warning messaging based on expected changes in healthcare visits given a set of meteorological variables, and can be further refined based on climate, rurality and age.

Recognition of climate-related risks for prehospital emergency medical service and emergency department in Finland - A Delphi study

BACKGROUND

Emergency departments (ED) and prehospital emergency medical services (EMS) will experience new or increasing challenges due to the changing climate. The aims of this study was to add knowledge about these challenges in Finland and to help EMS and ED operators to prepare for the effects of climate change.

METHODS

A two-round Delphi study was conducted. Ten participants expressed their views of climate change-related challenges currently and in the future, and how to prepare for challenges ahead. First-round questions based on the literature search about the climate-related impacts on EMS and ED. The stage one data was analysed by thematic analysis, which generated the second-round survey where the probability of the statements was estimated.

RESULTS

Various climate change-related challenges were recognized such as negative health impacts, the increased workload, difficulties with the EMS operations and problems with the functions of society. Preparation of action plans was considered important in case for incidents and emergencies.

CONCLUSION

The study indicated that climate change may cause various challenges for EMS and ED in Finland. To meet the future challenges, it is important to identify potential future risks and create plans to manage them. Further studies are needed to create climate resilient healthcare systems.

Estimating the Burden of Heat-Related Illness Morbidity Attributable to Anthropogenic Climate Change in North Carolina

Climate change is known to increase the frequency and intensity of hot days (daily maximum temperature ≥30°C), both globally and locally. Exposure to extreme heat is associated with numerous adverse human health outcomes. This study estimated the burden of heat-related illness (HRI) attributable to anthropogenic climate change in North Carolina physiographic divisions (Coastal and Piedmont) during the summer months from 2011 to 2016. Additionally, assuming intermediate and high greenhouse gas emission scenarios, future HRI morbidity burden attributable to climate change was estimated. The association between daily maximum temperature and the rate of HRI was evaluated using the Generalized Additive Model. The rate of HRI assuming natural simulations (i.e., absence of greenhouse gas emissions) and future greenhouse gas emission scenarios were predicted to estimate the HRI attributable to climate change. Over 4 years (2011, 2012, 2014, and 2015), we observed a significant decrease in the rate of HRI assuming natural simulations compared to the observed. About 3 out of 20 HRI visits are attributable to anthropogenic climate change in Coastal (13.40% [IQR: -34.90,95.52]) and Piedmont (16.39% [IQR: -35.18,148.26]) regions. During the future periods, the median rate of HRI was significantly higher (78.65%: Coastal and 65.85%: Piedmont), assuming a higher emission scenario than the intermediate emission scenario. We observed significant associations between anthropogenic climate change and adverse human health outcomes. Our findings indicate the need for evidence-based public health interventions to protect human health from climate-related exposures, like extreme heat, while minimizing greenhouse gas emissions.

City-level vulnerability to temperature-related mortality in the USA and future projections: a geographically clustered meta-regression

BACKGROUND

Extreme heat exposure can lead to premature death. Climate change is expected to increase the frequency, intensity, and duration of extreme heat events, resulting in many additional heat-related deaths globally, as well as changing the nature of extreme cold events. At the same time, vulnerability to extreme heat has decreased over time, probably due to a combination of physiological, behavioural, infrastructural, and technological adaptations. We aimed to account for these changes in vulnerability and avoid overstated projections for temperature-related mortality. We used the historical observed decrease in vulnerability to improve future mortality estimates.

METHODS

We used historical mortality and temperature data from 208 US cities to quantify how observed changes in vulnerability from 1973 to 2013 affected projections of temperature-related mortality under various climate scenarios. We used geographically structured meta-regression to characterise the relationship between temperature and mortality for these urban populations over the specified time period. We then used the fitted relationships to project mortality under future climate conditions.

FINDINGS

Between Oct 26, 2018, and March 9, 2020, we established that differences in vulnerability to temperature were geographically structured. Vulnerability decreased over time in most areas. US mortalities projected from a 2°C increase in mean temperature decreased by more than 97% when using 2003-13 data compared with 1973-82 data. However, these benefits declined with increasing temperatures, with a 6°C increase showing only an 84% decline in projected mortality based on 2003-13 data.

INTERPRETATION

Even after accounting for adaptation, the projected effects of climate change on premature mortality constitute a substantial public health risk. Our work suggests large increases in temperature will require additional mitigation to avoid excess mortality from heat events, even in areas with high air conditioning coverage in place.

FUNDING

The US Environmental Protection Agency and Abt Associates.

Extreme Weather and Climate Change: Population Health and Health System Implications

Extreme weather and climate events, such as heat waves, cyclones, and floods, are an expression of climate variability. These events and events influenced by climate change, such as wildfires, continue to cause significant human morbidity and mortality and adversely affect mental health and well-being. Although adverse health impacts from extreme events declined over the past few decades, climate change and more people moving into harm's way could alter this trend. Long-term changes to Earth's energy balance are increasing the frequency and intensity of many extreme events and the probability of compound events, with trends projected to accelerate under certain greenhouse gas emissions scenarios. While most of these events cannot be completely avoided, many of the health risks could be prevented through building climate-resilient health systems with improved risk reduction, preparation, response, and recovery. Conducting vulnerability and adaptation assessments and developing health system adaptation plans can identify priority actions to effectively reduce risks, such as disaster risk management and more resilient infrastructure. The risks are urgent, so action is needed now.

Estimating the Health-Related Costs of 10 Climate-Sensitive U.S. Events During 2012

Climate change threatens human health, but there remains a lack of evidence on the economic toll of climate-sensitive public health impacts. We characterize human mortality and morbidity costs associated with 10 climate-sensitive case study events spanning 11 US states in 2012: wildfires in Colorado and Washington, ozone air pollution in Nevada, extreme heat in Wisconsin, infectious disease outbreaks of tick-borne Lyme disease in Michigan and mosquito-borne West Nile virus in Texas, extreme weather in Ohio, impacts of Hurricane Sandy in New Jersey and New York, allergenic oak pollen in North Carolina, and harmful algal blooms on the Florida coast. Applying a consistent economic valuation approach to published studies and state estimates, we estimate total health-related costs from 917 deaths, 20,568 hospitalizations, and 17,857 emergency department visits of $10.0 billion in 2018 dollars, with a sensitivity range of $2.7-24.6 billion. Our estimates indicate that the financial burden of deaths, hospitalizations, emergency department visits, and associated medical care is a key dimension of the overall economic impact of climate-sensitive events. We found that mortality costs (i.e., the value of a statistical life) of $8.4 billion exceeded morbidity costs and lost wages ($1.6 billion combined). By better characterizing health damages in economic terms, this work helps to shed light on the burden climate-sensitive events already place on U.S. public health each year. In doing so, we provide a conceptual framework for broader estimation of climate-sensitive health-related costs. The high health-related costs associated with climate-sensitive events highlight the importance of actions to mitigate climate change and adapt to its unavoidable impacts.

Mortality and morbidity associated with ambient temperatures in Taiwan

BACKGROUND

This study evaluated integrated risks of all-cause mortality, emergency room visits (ERVs), and outpatient visits associated with ambient temperature in all cities and counties of Taiwan. In addition, the modifying effects of socio-economic and environmental factors on temperature-health associations were also evaluated.

METHODS

A distributed lag non-linear model was applied to estimate the cumulative relative risks (RRs) with confidence intervals of all-cause mortality, ERVs, and outpatient visits associated with extreme temperature events. Random-effect meta-analysis was used to estimate the pooled RR of all-cause mortality, ERVs, and outpatient visits influenced by socio-economic and environmental factors.

RESULTS

Temperature-related risks varied with study area and health outcome. Meta-analysis showed greater all-cause mortality risk occurred in low temperatures than in high temperatures. Integrated RR of all-cause mortality was 1.71 (95% confidence interval [CI]:1.43-2.04) in the 5th percentile temperature and 1.10 (95% CI: 1.05-1.15) in the 95th percentile temperature, while the lowest mortality risk was in the 60th percentile temperature (22.2 °C). Risk for ERVs increased when temperature increased (RR was 1.21 [95% CI: 1.17-1.26] in 95th percentile temperature), but risk of outpatient visits increased at low temperatures (RR was 1.06 [95% CI: 1.01-1.12] in the 5th percentile temperature). Certain socio-economic factors significantly modified low-temperature-related mortality risks, including number of employed populations, elders living alone from lower-income families, and public and medical services.

CONCLUSIONS

This study found that mortality and outpatient visits were higher at low temperature, while ERVs risk was higher at high temperature. Future plans for public health and emerging medical services responding to extreme temperatures should consider regional and integrated evaluations of temperature-related health risks and modifying factors.