Heat waves and adaptation: A global systematic review

A new approach to estimate the heat thresholds at the county level in China

BACKGROUND

High temperature beyond the comfort threshold is the main hazard to cause heat-related mortality. However, existing methods of defining the heat thresholds are usually based on case studies in data-rich regions and rarely considers the acclimatization.

METHODS

Based on the temperature-mortality relationship observed in 36 locations covering all six major climate zones in China, we found that the relative risk (RR) of heat-related mortality and the annual frequency of temperature (AFT) have a power function relationship (adjusted R2 = 0.74)), and the association is independent to the variation of the temperature across the territory. Furthermore, the association is slightly changed when the GDP/capita, proportion of elderly population and latitude are adjusted. According to this association, we proposed a new method to choose the heat threshold at finer resolution using only AFT. As the temperature frequency is easy to calculate, this method can be promoted to any geographical location without mortality data.

RESULTS

According to the relationship between AFT and RR, using the daily time series of temperature at 2405 observation stations in China, we estimated and mapped the distribution of heat thresholds at the county level across China. We find that when the AFT is just 1 day per year, the corresponding RR is approximately 1.4 (95% CI, 1.2-1.8). As the AFT increases to 5 days per year, the RR decreases to about 1.2 (95% CI, 1.1-1.3). When the AFT reached 10 days per year, the RR further decreased to about 1.05 (95% CI, 1.0-1.1).

CONCLUSIONS

This study advances the understanding on the driver of human beings' adaptation to high temperature. It also contributes significantly to the research on heat-related mortality in the context of global climate change.

Heat Acclimation Enhances Brain Resilience to Acute Thermal Stress in Clarias fuscus by Modulating Cell Adhesion, Anti-Apoptotic Pathways, and Intracellular Degradation Mechanisms

Global climate change presents a significant challenge to aquatic ecosystems, with ectothermic fish being particularly sensitive to temperature fluctuations. The brain plays a crucial role in perceiving, regulating, and adapting to thermal changes, and its response to heat stress is crucial for survival. However, the molecular mechanisms underlying heat stress and acclimation in fish brains remain poorly understood. This study aimed to investigate the adaptive mechanisms of Hong Kong catfish (Clarias fuscus) brains under heat acclimation and acute heat stress using transcriptome analysis. Fish were divided into two groups: a normal temperature group (NT, 26 °C for 90 days) and a heat-acclimated group (HT, 34 °C for 90 days), followed by acute heat stress (34 °C for 72 h) and recovery (26 °C for 72 h). Heat acclimation improved C. fuscus tolerance to acute heat stress, with faster gene responses and stronger neuroprotection. Key pathways enriched included cell adhesion and ECM-receptor interactions during recovery. Apoptosis regulation was balanced, with the HT group upregulating anti-apoptotic genes to mitigate neuronal cell death. Additionally, the lysosome-phagosome pathway was activated during recovery, facilitating the transport of lysosomal enzymes and the clearance of damaged cellular components, aiding neuronal repair. Ribosome biogenesis was suppressed under heat stress to conserve energy, but this suppression was less pronounced in the HT group. In summary, heat acclimation enhances neural protection in C. fuscus brains by promoting neuronal repair, suppressing apoptosis, and activating lysosomal pathways, thereby improving tolerance to acute heat stress. These findings offer a molecular basis for breeding heat-tolerant fish species in aquaculture, and deepen our understanding of thermal adaptation in aquatic animals amid global climate change.

Awareness and preparedness of health systems and emergency medicine systems to the climate change challenges and threats: an international survey

BACKGROUND AND IMPORTANCE

Climate change is widely recognised as a critical public health challenge.

OBJECTIVE

The objective of this study was to assess the awareness, preparedness and mitigation plans for climate change threats.

DESIGN, SETTINGS AND PARTICIPANTS

A cross-sectional observational study targeting emergency medical societies in different countries was conducted between 15 February and 15 March 2024.

INTERVENTION OR EXPOSURE

The survey featured 16 closed questions on climate change awareness, preparedness and risks. Focus groups of 4-6 members were organised by country. Results were correlated to income levels, United Nations (UN) regional classification and the World Risk Index.

OUTCOME MEASURE AND ANALYSIS

The questions were ranked using a Likert-like scale from 0 to 9 (9 being the highest). Descriptive statistics used central tendency estimators, and inferential analysis used chi-square and Kruskal-Wallis tests, with the significance level set at P  < 0.05.

RESULTS

Forty-two focus groups responded, representing 36 countries: 21 (50%) high-income, seven (16.7%) low-income, five (11.9%) lower middle-income and nine (21.4%) upper middle-income countries, representing 31 of the 22 UN regions. According to the World Risk Index, the respondent countries belonged to the different categories as follows: very low risk, 6 (14%); low risk, 8 (19%); medium risk, 5 (12%); high risk, 8 (19%) and very high risk, 14 (34%). The estimated impact of climate change on national health systems had a mean score of 6.75 (SD = 2.16), while on Emergency Medical Systems was 6.96 (SD = 2.05). Overall, assessment and preparedness measures were reported by just 21.4 and 37.6% of respondents, respectively. Analysis by income did not show significant differences, with the exception of food supply. The main differences in the analysis by region were the risks of extreme weather events, vector-borne diseases and wildfires, whereas the World Risk Index was food and chain of supplies. Education and integration of health services were indicated by all as the main mitigation actions.

CONCLUSION

Geographical position and country risk index influence risk perception among focus groups more than income economy, with vector-borne diseases, extreme weather events and food shortages being the threats with the most variability. The most important actions identified to mitigate Climate Change effects are educational and strategic plans.

A digital heat early warning system for older adults

Extreme heat events lead to considerable health burden and are becoming more severe and frequent, calling for the development of effective population-based and individualised heat early warning systems. We developed an individualised heat early warning system and tested it in 78 older adults' ( ≥ 65 years) homes in Southeast Queensland, Australia. Quantitative and qualitative data from this proof-of-concept testing study showed that the Ethos system performed well on a standard usability scale (mean score of 78 on the System Usability Scale). Following a summer-time use of this early warning system, there were increases in heat preparedness (P < 0.001, marginal homogeneity tests) but no significant increases in heat health risk perception or the uptake of low-cost cooling measures (e.g., hand/forearm bath, fans). This proof-of-concept research demonstrated the usability of this tailored, actionable, real-time digital heat early warning system, although the effectiveness of the system remains to be evaluated in a robust trial design.

Psychometric analysis of work organization and fatigue instruments and their relationship with occupational accidents: a structural equation modeling approach

BACKGROUND

Work organization significantly impacts occupational incidents and fatigue in hospital settings, particularly among nurses. This study aimed to evaluate the psychometric properties of instruments measuring work organization and fatigue and to examine their relationship with occupational accidents.

METHODS

A cross-sectional study was conducted in 2019 with 200 nurses working in hospitals in Qom, Iran using the stratified sampling method. Data were collected using three standardized tools: the Work Organization Questionnaire, the Fatigue Checklist, and a demographic information questionnaire. Structural equation modeling was employed to analyze the data, while instrument validity and reliability were assessed through Cronbach's alpha, composite reliability, and average variance extracted (AVE). Analysis was performed using Smart PLS and SPSS V20.

RESULTS

The analysis revealed a significant relationship between work organization and occupational accidents (t = 3.22, p < 0.05). However, the relationships between work organization and fatigue (t = 0.03) and between fatigue and occupational accidents (t = 1.49) were not statistically significant. The Work Organization Questionnaire (WOAQ) demonstrated robust validity and reliability, making it suitable for assessing occupational risks in hospital environments. In contrast, the Fatigue Questionnaire (CIS) exhibited acceptable validity but insufficient reliability (Cronbach's alpha < 0.7), highlighting the need for further refinement.

CONCLUSION

This study revealed that the Work Organization Questionnaire has acceptable validity and reliability, making it suitable for hospital settings, while the Fatigue Questionnaire requires further revision. It is recommended that hospital administrators optimize work schedules and provide fatigue management training, and policymakers utilize validated tools to reduce occupational risks and enhance workplace safety.

Leveling of triggers: a comprehensive summative content analysis of factors contributing to physical violence in emergency medical services

BACKGROUND

The literature has identified numerous factors that contribute to workplace violence, ranging from environmental stressors to interpersonal conflict. However, a gap remains in our understanding of the specific factors associated with physical violence, particularly concerning its frequency and perceived significance.

METHODS

A summative content analysis was conducted via the electronic survey platform Porsline in Iran for data collection. In April 2024, EMTs working in urban, road, and air bases in western Iran participated in the study. In total, 358 EMTs were selected via convenience sampling. They provided open-ended responses to the following question: "What do you believe are the most significant factors contributing to physical violence in your workplace?"

RESULTS

The analysis resulted in a comprehensive list of 1,407 descriptions, organized into 20 subcategories and further consolidated into ten main categories. The category with the highest frequency was "legal and policy deficiencies," with a frequency of 3103, and the category with the lowest frequency was "workplace culture and professional satisfaction," with 579. The categories based on frequency and significance included "legal and policy deficiencies," "cultural and societal barriers," "insufficient training and practical skills," "shortcomings in organizational safety and support," "interpersonal and operational pressures," "organizational culture and workforce dynamics," "barriers to effective prehospital care," "resource and infrastructure limitation," "challenges in interagency coordination and support," and "workplace culture and professional satisfaction."

CONCLUSION

Legal reforms addressing legal inadequacies, enhancing organizational support systems, and implementing targeted training programs to mitigate conflicts are essential for fostering a safer working environment. By addressing these pressing issues, healthcare facilities can enhance emergency care, safeguard the well-being of emergency responders, and increase the quality of emergency medical services for communities.

Challenges of providing of special care services in hospitals during emergencies and disasters: a scoping review

BACKGROUND

The ability of hospitals to provide special care services for critically ill or injured patients during emergencies and disasters poses very significant challenges that necessitate the response in-place plans. the increasing frequency of such events, coupled with limited hospital resources and increasing patient volumes, underscores the urgency of addressing these issues. Specifically, this study aims to identify the challenges faced by hospitals in providing special services during disasters.

METHOD

This scoping review, conducted in 2024, based upon the framework developed by Arksey and O'Malley. An extensive search of Literature searching was performed using gray literature and databases including Google Scholar, PubMed, Web of Science, and Scopus. Applying the selection criteria, a total of 33 relevant studies were identified that discuss the challenges faced when providing special care services in hospitals during emergencies and disasters. Results are presented in accordance with the PRISMA checklist to ensure quality and transparency. Data was analyzed through a systematic coding process where common themes across the studies were identified.

RESULTS

This review identified 15 distinct challenges associated with providing special care services in hospitals during emergencies and disasters: limited resources, inadequate infrastructure, lack of pre-hospital care, financial constraints, failures in the emergency response system, triage, deficiencies in management structure, planning, and preparation, communication and coordination deficits, training and protocols development, employee welfare challenges, challenges of continuity of care, increased demand, different and complex needs of patients, ethical challenges, imbalance in distribution of service resources.

CONCLUSIONS

Response in a hospital to the needs of special care during a disaster has to be responded to with more effective preparedness through comprehensive disaster preparedness plans, better communication and coordination, and training of staff and allocation of resources. In particular, standardized triage protocols and ethical frameworks will provide the foundation for the optimization of resource use in emergency responses. Better communication among departments and also with other outside organizations will improve how resources are used to better achieve good patient outcomes within emergency responses.

The Impact of Global Warming on the Rise in Heat-Related Illnesses in Emergency Medical Services

PURPOSE

Global warming is one of the critical problems affecting health, society, and the economy. High temperatures are linked to an increase in heat-related illnesses, which have significantly impacted the public health system, particularly emergency medical services (EMS). Analyzing the pattern of heat-related illness cases in EMS can improve resource utilization and preparedness within the public health system.

PATIENTS AND METHODS

A retrospective study was conducted on EMS data from Srinagarind Hospital, Thailand, covering the summer months (February to May) from 2020 to 2024. Patients with heat-related illnesses were identified in the EMS database using the 10th revision of the International Classification of Diseases (ICD-10) version 2019, specifically codes under "T67 Effects of Heat and Light", which include heat stroke, heat syncope, heat cramps, heat exhaustion, and heat fatigue.

RESULTS

A total of 136 EMS operations from the hospital's database were analyzed. In the summer 2024 group, 95.7% (N=44) of the patients were male. The majority of EMS triage cases required resuscitation (P = 0.020). Outdoor activity was identified as a significant factor related to heat illness, with rates of 83.3%, 92.9%, 93.3%, 97.1%, and 93.5% over the five years of the study. The activation time was 1.30 minutes for the summer of 2024 and 1.24 minutes for the summer of 2023. Notably, the average scene time in the summer 2024 group was significantly longer at 25.2 minutes, compared to 12.0 minutes in the summer 2020 group (P<0.001).

CONCLUSION

Outdoor activity was the most significant risk factor associated with increased heat-related illnesses. Other contributing factors included male gender, age between 20-40 years, scene temperatures above 35°C, and prolonged scene times exceeding 15 minutes.

Development, validation and reliability of scales and items for heat wave risk assessment of pregnant women

INTRODUCTION

The 1.2 °C rise of global ambient temperature since the pre-industrial era has led to an increase the intensity and frequency of heatwaves. Given the heightened vulnerability of pregnant women to heat stress, there is an urgent need for tools which accurately assess the knowledge, risk, and perception of pregnant woman toward heatwaves, enabling effective policy actions. In this research, we developed and validated tools to evaluate pregnant women's perceptions of heat wave risks and behaviors.

METHOD

We developed 50 items across seven constructs using the Health Belief Model, identified through a systematic literature review. The constructs comprised 8 Knowledge(K) items, 4 in Perceived Vulnerability (PV), 5 in Perceived Severity (PS), 6 in Perceived Benefit (PB), 4 in Perceived Barrier (PBa), 5 in Cue to Action(Cu) and 18 in Adaptation(A). Cognitive testing was performed with a separate group of pregnant women(n = 20). The tested tools were then administered to 120 pregnant women residing during the spring-summer 2023. Construct validation utilized exploratory factor analysis.

RESULTS

The Principal Axis Factoring Method was employed in the EFA with oblimin rotation for 51 items, considering communality > 0.20, and aiming to extract three factors. Across the three factors with Cronbach's alpha > 0.70, a total of 11 items were distributed. Factor 1 included Perceived Severity (PS1, PS2, PS3 and PS5); Factor 2 included Cue to Action (Cu1, Cu2, Cu3, and Cu4); and Factor 3 encompassed Perceived Vulnerability (PV1, PV2, PV4). Only two of the retained items had factor loadings > 0.50, namely PV4 and PS5. Consequently, the three constructs measuring Perceived Severity, Cues to Action, and Perceived Vulnerability using the HBM among pregnant women were deemed valid.

CONCLUSION

Our study has successfully validated a highly reliable tool which stands ready for application in assessing pregnant women's risk perception regarding heatwaves.

Assessment of nursing managers' awareness and hospital preparedness for disasters: a cross-sectional study

INTRODUCTION

Preparedness, focused on planning, training, and research, is one of the primary stages of the disaster management cycle. Accordingly, this study was conducted to determine the level of awareness in nursing managers and the preparedness of hospitals for disasters in the hospitals of Sanandaj, the capital of Kurdistan Province.

METHODS

This cross-sectional study was conducted in 2023, with a total of 167 Nursing Managers in Sanandaj selected as the research sample using a census approach. Data were collected using a demographic information form, WHO Hospital Emergency Response Checklist, and managers' emergency awareness questionnaire. Data were analyzed using Chi-square tests, Fisher's exact test, independent t-tests, analysis of variance (ANOVA), and Pearson correlation. Data analysis was performed using SPSS v26 (P < 0.05).

FINDINGS

The results indicated that the overall mean score of managers' awareness was 77.89%, categorized as good. The assessment of hospital preparedness showed that the overall emergency preparedness level of hospitals in Sanandaj was 69.23%, considered strong. Among the dimensions of hospital preparedness, the highest score was in the command-and-control dimension at 83.33%, while the lowest was in the human resources dimension at 56.66%.

CONCLUSION

The findings indicated a high level of awareness among nursing managers and a strong level of hospital preparedness in Sanandaj. However, improving and enhancing specific dimensions may require targeted educational and organizational approaches.

Coping with extreme heat: current exposure and implications for the future

A preview of how effective behavioral, biological and technological responses might be in the future, when outdoor conditions will be at least 2°C hotter than current levels, is available today from studies of individuals already living in extreme heat. In areas where high temperatures are common-particularly those in the hot and humid tropics-several studies report that indoor temperatures in low-income housing can be significantly hotter than those outdoors. A case study indicates that daily indoor heat indexes in almost all the 123 slum dwellings monitored in Kolkata during the summer were above 41°C (106°F) for at least an hour. Economic constraints make it unlikely that technological fixes, such as air conditioners, will remedy conditions like these-now or in the future. People without access to air conditioning will have to rely on behavioral adjustments and/or biological/physiological acclimatization. One important unknown is whether individuals who have lived their entire lives in hot environments without air conditioning possess natural levels of acclimatization greater than those indicated by controlled laboratory studies. Answering questions about the future will require more studies of heat conditions experienced by individuals, more information on indoor versus outdoor heat conditions, and a greater understanding of the behavioral and biological adjustments made by people living today in extremely hot conditions.

Health system adaptations for extreme heat: Protocol for an international scoping review of reviews

OBJECTIVE

The objective of this study is to map the international evidence for extreme heat related adaptation strategies by health systems, with a particular focus on how heat-vulnerable populations and local situational awareness are considered in these strategies.

INTRODUCTION

Since the Paris Climate Accords in 2015, awareness has increased of the health risks posed by extreme heat along with interest in adaptations which aim to reduce heat-health-risks for vulnerable populations. However, the extant literature on these adaptations suggest they are insufficient, and call for research to examine whether, how, and what adaptations for extreme heat are effective as public health interventions.

INCLUSION CRITERIA

We will include English-language review articles describing and/or evaluating health system adaptations for extreme heat. Health systems will be defined broadly using the WHO Building Blocks model [1] and adaptations will range from the individual level to institutional, regional and national levels, with particular attention to localisation and the protection of vulnerable individuals.

METHODS

A comprehensive literature search of the published literature will be conducted using MEDLINE, Embase, CINAHL, the Cochrane Library and Web of Science. Searches will be limited to reviews published since 2015 in the English language. Results will be exported to EndNote for screening (with a sample checked by two reviewers to ensure consistency). A complementary search for related reports by major international agencies (e.g. WHO; International Association of Emergency Managers), as well as local searches for current guidance and case studies, will be conducted in parallel. Data from included papers will be presented in tables with a narrative commentary.

Vulnerability assessment of heat waves within a risk framework using artificial intelligence

Current efforts to adapt to climate change are not sufficient to reduce projected impacts. Vulnerability assessments are essential to allocate resources where they are needed most. However, current assessments that use principal component analysis suffer from multiple shortcomings and are hard to translate into concrete actions. To address these issues, this article proposes a novel data-driven vulnerability assessment within a risk framework. The framework is based on the definitions from the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, but some definitions, such as sensitivity and adaptive capacity, are clarified. Heat waves that occurred between 2001 and 2018 in Quebec (Canada) are used to validate the framework. The studied impact is the daily mortality rates per cooling degree-days (CDD) region. A vulnerability map is produced to identify the distributions of summer mortality rates in aggregate dissemination areas within each CDD region. Socioeconomic and environmental variables are used to calculate impact and vulnerability. We compared abilities of AutoGluon (an AutoML framework), Gaussian process, and deep Gaussian process to model the impact and vulnerability. We offer advice on how to avoid common pitfalls with artificial intelligence and machine-learning algorithms. Gaussian process is a promising approach for supporting the proposed framework. SHAP values provide an explanation for the model results and are consistent with current knowledge of vulnerability. Recommendations are made to implement the proposed framework quantitatively or qualitatively.

Heat stress reduces brown adipose tissue activity by exacerbating mitochondrial damage in type 2 diabetic mice

Epidemiological evidence shows that diabetic patients are susceptible to high temperature weather, and brown adipose tissue (BAT) activity is closely related to type 2 diabetes (T2DM). Activation of BAT under cold stress helps improve T2DM. However, the impact of high temperature on the activity of BAT is still unclear. The study aimed to investigate the impact of heat stress on glucose and lipid metabolism in T2DM mice by influencing BAT activity. High-fat feeding and injecting streptozotocin (STZ) induced model of T2DM mice. All mice were randomly divided into three groups: a normal(N) group, a diabetes (DM) group and a heat stress diabetes (DMHS) group. The DMHS group received heat stress intervention for 3 days. Fasting blood glucose, fasting serum insulin and blood lipids were measured in all three groups. The activity of BAT was assessed by using quantitative real-time PCR (qRT-PCR), electron microscopy, and PET CT. Furthermore, the UHPLC-Q-TOF MS technique was employed to perform metabolomics analysis of BAT on both DM group and DMHS group. The results of this study indicated that heat stress aggravated the dysregulation of glucose and lipid metabolism, exacerbated mitochondrial dysfunction in BAT and reduced the activity of BAT in T2DM mice. This may be related to the abnormal accumulation of branched-chain amino acids (BCAAs) in the mitochondria of BAT.