The Effect of Heat Events on Prehospital and Retrieval Service Utilization in Rural and Remote Areas: A Scoping Review

Introduction: It is well-established that heatwaves increase demand for emergency transport in metropolitan areas; however, little is known about the impact of heat events on demand for prehospital retrieval services in rural and remote areas, or how heatwaves are defined in this context. Inclusion Criteria: Papers were eligible for inclusion if they reported on the impact of a heat event on the activity of a prehospital and retrieval service in a rural or remote area. Methods: A search of PubMed, Cochrane, Science Direct, CINAHL, and Google Scholar databases was undertaken on August 18, 2020 using search terms related to emergency medical transport, extreme heat, and rural or remote. Data relevant to the impact of heat on retrieval service activity were extracted, as well as definitions of extreme heat. Results: Two papers were identified, both from Australia. Both found that heat events increased the number of road ambulance call-outs. Both studies used the Excess Heat Factor (EHF) to define heatwave periods of interest. Conclusions: This review found almost no primary literature on demand for prehospital retrieval services in rural and remote areas, and no data specifically related to aeromedical transport. The research did recognize the disproportionate impact of heat-related increase in service demand on Australian rural and regional health services. With the effects of climate change already being felt, there is an urgent need for more research and action in this area.

999Impact of Heatwaves on use of health services (GP and Emergency department visits)

Background Heatwaves are associated with increases in mortality and morbidity (mostly hospitalisations). However, evidence regarding heatwave impacts on the use of frontline health-services such as general practitioner (GP) consultations and emergency department (ED) services is limited. This study quantified the impact of heatwaves on the use of GP and ED services in Adelaide. Methods Data on GP services (2011-2016) from the Medicare Benefits Schedule and ED visits (2013-2018) were obtained from the Australian Bureau of Statistics and the Department of Health, respectively. Heatwaves were defined using Excess Heat Factor. Using time-stratified case-crossover models, we modelled heatwave-severity (low, severe/extreme) against the use of GP and ED services in the warm-season (October-March). Effect estimates are reported as relative risks (RRs). Results Total GP visits decreased during low-intensity heatwaves and increased during severe/extreme heatwaves (RR 1.14; 95%CI: 1.13-1.15). The highest increases during severe/extreme heatwaves were observed for respiratory (RR 1.36; 95%CI: 1.27-1.45) and psychiatric services. While ED visits decreased overall during low-intensity and severe/extreme heatwaves, those due to heat-light disorders (RR 4.23; 95%CI: 2.98-6.00), volume depletion, and respiratory diseases increased during severe/extreme heatwaves. Conclusions There were significant increases in the use of GP and specific ED services during heatwaves in Adelaide. Further research is needed to identify the intrinsic and extrinsic vulnerability factors contributing to these increases in Adelaide and other Australian cities. Key messages Impacts of heatwaves extend beyond mortality to include frontline health-services (GP/EDs) that are already challenged. Evidence presented may assist policymakers for resource allocation and healthcare workforce capacity building.

217Using excess heat factor to measure effect of heatwave severity on foodborne disease incidence

Background This study aims to analyse the distribution characteristics of ideal cardiovascular health (ICH) metrics status of the oldest-old and centenarians, and also to explore the relationships with disability and quality of life. Methods 1002 centenarians and 798 oldest-old were included in the analysis. ICH, disability and quality of life were assessed according to standard methods. Results The median number of ICH metrics among centenarians and oldest-old were 4 (4-5) and 3(3-5) respectively. The highest proportion of ICH metrics at ideal levels were glucose (90.2%), BMI (89.8%), and smoking (89.4%), the lowest proportion of ICH metrics at ideal level was blood pressure (8.3%). The disability rates of BADL and IADL decreased with the number of ICH metrics. BADL disability changed from 100.0% to 73.2%, and the IADL disability rate dropped from 100% to 80.0%. BADL disability rate decreased from 45.0% to 25.3% and IADL disability decreased from 100.0% to 57.1% among the oldest-old. The EQ-5D vas, EQ-5D score showed increasing trend along with the number of ICH metrics (p < 0.05). Compared with centenarians who had only 0-2 ICH metrics, the ORs for BADL disability were 0.82, 0.66, 0.52, 0.44, and the ORs for IADL disability were 0.74, 0.65, 0.58, 0.41 for those with 3, 4, 5, ≥6 ICH metrics. Conclusions ICH metrics of centenarians and oldest-old were at a relatively good level, and there was a strong and independent inverse relationship between ICH metrics with both disability and lower quality of life. Key messages This was the first survey about the distribution of ICH metrics and association with both disability and quality of life based on elderly aged over 80 years old. The results highlighted the importance of cardiovascular prevention even at 80 years and over, which made up for the evidence gap based on this age group.

Assessing Heatwaves and Their Association with North African Dust Intrusions in the Algarve (Portugal)

Heatwaves are an extreme meteorological event in which affected populations may also be exposed to deteriorated air quality conditions due to the increase in air pollutant concentrations, such as PM10 (particulate matter < 10 µg/m3). In order to identify heatwaves (1973–2019) in the region of Faro (Algarve) during the hot season (April–September), the Excess Heat Factor (EHF) index was applied. The Mann–Kendall test revealed an upward trend in three heatwave metrics in Faro, and the trend of accumulated heat load (EHF load) was also positive as would be expected, but its signal was not statistically significant. An inventory of North African dust events (2006–2019) was made, and their simultaneous occurrence with heatwaves was assessed, pointing to only 20% of dust events of the Sahara occurring simultaneously with heatwave days. A cluster analysis was conducted on daily geopotential height fields at 850 hPa level over the 2006–2019 period, and four distinct patterns were identified as the most prominent synoptic circulations promoting both heatwave conditions and North African dust over the Algarve.

The effect of heat events on prehospital and retrieval service utilisation in rural and remote areas: a scoping review

IntroductionIt is well established that heatwaves increase demand for emergency transport in metropolitan areas, however little is known about the impact of heat events on demand for prehospital retrieval services in rural and remote areas, or how heatwaves are defined in this context.Inclusion criteriaPapers were eligible for inclusion if they reported on the impact of a heat event on the activity of a prehospital and retrieval service in a rural or remote area.MethodsA search of PubMed, Cochrane, Science Direct, CINAHL and Google Scholar databases was undertaken on 18 August 2020, using search terms related to emergency medical transport, extreme heat and rural or remote. Data relevant to the impact of heat on retrieval service activity was extracted, as well as definitions of extreme heat.ResultsTwo papers were identified, both from Australia. Both found that heat events increased the number of road ambulance call-outs. Both studies used the Excess Heat Factor to define heatwave periods of interest.ConclusionsThis review found almost no primary literature on demand for prehospital retrieval services in rural and remote areas, and no data specifically related to aeromedical transport. The research did recognise the disproportionate impact of heat-related increase in service demand on rural and regional health services. With the effects of climate change already being felt, there is an urgent need for more research and action in this area.

Hotspots of extreme compound drought and heatwaves: Role of feedback and climate oscillations

&lt;p&gt;Compound weather events arise from combination of multiple climatic drivers or hazards and often result in disastrous socio-economic impacts. Compound drought and heatwave (CDHE) events have received considerable attention in recent years, but limited attention is given towards the understanding of feedback relationships between droughts and heatwaves at global hotspots of the compound events. Here, we identify the potential hotspots of extreme compound drought and heatwaves (ECDH) over the globe using standardized precipitation index (SPI) and Excess heat factor (EHF) as metrics for droughts and heatwaves, respectively. Besides the well know positive feedback between droughts and heatwaves, i.e., heatwaves amplify droughts and vice-versa, we hypothesize and test the possibility of negative feedback at distinct hotspots where heatwaves tend to abate droughts. Multiple hotspots were identified with positive and negative feedbacks among drought and heatwave intensities, supporting our hypothesis. We also analyzed the role of different local and large-scale global drivers (such as El-Ni&amp;#241;o Southern Oscillation) on the feedbacks at the hotspots. Our analysis has implications in predicting extreme compound droughts and heatwaves and provides new insights that will foster further research in this direction.&lt;/p&gt;

Recent Trends in Heat-Related Mortality in the United States: An Update through 2018

Much research has shown a general decrease in the negative health response to extreme heat events in recent decades. With a society that is growing older, and a climate that is warming, whether this trend can continue is an open question. Using eight additional years of mortality data, we extend our previous research to explore trends in heat-related mortality across the United States. For the period 1975–2018, we examined the mortality associated with extreme-heat-event days across the 107 largest metropolitan areas. Mortality response was assessed over a cumulative 10-day lag period following events that were defined using thresholds of the excess heat factor, using a distributed-lag nonlinear model. We analyzed total mortality and subsets of age and sex. Our results show that in the past decade there is heterogeneity in the trends of heat-related human mortality. The decrease in heat vulnerability continues among those 65 and older across most of the country, which may be associated with improved messaging and increased awareness. These decreases are offset in many locations by an increase in mortality among men 45–64 (+1.3 deaths per year), particularly across parts of the southern and southwestern United States. As heat-warning messaging broadly identifies the elderly as the most vulnerable group, the results here suggest that differences in risk perception may play a role. Further, an increase in the number of heat events over the past decade across the United States may have contributed to the end of a decades-long downward trend in the estimated number of heat-related fatalities.

Heatwave-related Mortality in Australia: Who's impacted the most?

Background The impacts of heatwaves on the risk of mortality have been well-documented worldwide. However, impacts are not equally spread across the population with certain subgroups and locations affected more than others, warranting local evidence to guide and improve prevention and adaptation strategies. The objectives of this study were to identify the person and area-level socio-demographic, health, and environmental factors that modify the heatwave-mortality association in Australia. Methods Warm-season (October-March) mortality (2007-2017) were obtained from the Australian Bureau of Statistics. Heatwaves were defined using Excess Heat Factor, a normalised metric of heatwave severity. A time-stratified case-crossover design was used to model heatwave-mortality associations at the Statistical Areas 2 (SA2) spatial unit. Effect modification by person and area-level factors was assessed using interaction terms. Results Nationally, mortality increased by 2% (Relative Risk-RR 1.02; 95%CI: 1.01-1.03) during heatwaves with 1418 excess deaths (95%CI: 723-2113). But impacts varied with the highest effect observed in Adelaide (RR 1.08; 95%CI: 1.04-1.12) and Regional Tasmania (RR 1.11; 95%CI: 1.04-1.18). A gradient of impact was found within locations, for example, vulnerable SA2s in Adelaide were featured by a higher proportion of people in rental housing, inaccessibilities (vehicle and internet), low vegetation, newer houses, and a prevalence of respiratory and psychological diseases. Person-level factors included those: renting privately, with a low English-speaking ability, with chronic health conditions (diabetes, asthma/chronic obstructive pulmonary diseases) and using antidepressants, anxiolytics and sedative medications. Conclusions Our results, leveraging person and area-level linked data, highlight the need to consider contextual and individual risk factors and the importance of developing place-based targeted interventions to reduce heatwave health impacts. Key messages Heatwaves increase mortality in Australia. Heatwave-vulnerability is determined by individual and community-level factors.

India can't Wait to Act upon Climate Change as Heatwaves Claim Life

&lt;p&gt;In the recent past, India has experienced an increase in daily maximum and minimum temperature by 0.8 to 1 &amp;#176;C and 0.2 to 0.3 &amp;#176;C, respectively, along with an increased number of heatwave days. Human fatality, morbidity and discomfort are often reported due to the frequent heatwaves in India. To understand the effect of humidity in heatwaves over India, here in this study, we have classified the heatwaves into oppressive (high temperature and high humidity) and extreme (high temperature and low humidity) using excess heat factor approach. The rate of increase in oppressive heatwave days is exceeding that of the extreme heatwave days, even though the total number of oppressive heatwave days is fewer than the extreme heatwave days in the considered period (1953 to 2013). Moreover, the oppressive heatwave days are found to be the fatal one, as it is well correlated with the heat-related deaths in India.&lt;/p&gt;&lt;p&gt;As per COP 21 agreement, countries pledged to maintain the global temperature well below a 2 &amp;#176;C above the pre-industrial levels while attempting to limit the same to 1.5 &amp;#176;C. Taking these two warming scenarios, we have identified the heatwave events in near-future (2035 to 2065) and far-future (2070 to 2100). The number of oppressive heatwave days is expected to show an alarming five-fold increase at 2 &amp;#176;C warming (comparing to the period 1976 to 2005) by the end of the century. Limiting the warming to 1.5 &amp;#176;C from the proposed 2 &amp;#176;C results in a 67% reduction in oppressive heatwave days. A substantial jump in the number of oppressive heatwave days when compared with extreme heatwave days proposes that the Indian population is expected to be severely affected by heatwaves in the future amidst inadequate adaptive measures.&lt;/p&gt;