The influence of meteorological factors on the occurrence of trauma and motor vehicle collisions in Tokyo

Good weather for a ride (or not?): how weather conditions impact road accidents - a case study from Wielkopolska (Poland)

This study offers a likely assessment of extreme meteorological events' impact on human perceptivity, frame of mind or even health during driving which might have had a consequence as a car accident. Research covered an analysis of car accidents during period 2010-2019 in the Wielkopolska (Poland) and four indices like maximum daily temperature, maximum value of humidex, difference between maximum temperatures observed from day to day and also difference between mean atmospheric pressure at the sea level observed from day to day. A distributed lag nonlinear model (DLNM) approach was used to obtain the relationship between these indices and car accidents. Our finding evidence that the "good weather for a ride" conditions are actually generating an increased risk of accidents. For indices related to high temperature, i.e., maximum temperature and humidex, it was possible to identify the critical values by which the risks of car accidents were the highest.

Enhancing health resilience in Japan in a changing climate

Climate change poses significant threats to human health, propelling Japan to take decisive action through the Climate Change Adaptation Act of 2018. This Act has led to the implementation of climate change adaptation policies across various sectors, including healthcare. In this review, we synthesized existing scientific evidence on the impacts of climate change on health in Japan and outlined the adaptation strategies and measures implemented by the central and local governments. The country has prioritized tackling heat-related illness and mortality and undertaken various adaptation measures to mitigate these risks. However, it faces unique challenges due to its super-aged society. Ensuring effective and coordinated strategies to address the growing uncertainties in vulnerability to climate change and the complex intersectoral impacts of disasters remains a critical issue. To combat the additional health risks by climate change, a comprehensive approach embracing adaptation and mitigation policies in the health sector is crucial. Encouraging intersectoral communication and collaboration will be vital for developing coherent and effective strategies to safeguard public health in the face of climate change.

Evaluating the short-term effect of ambient temperature on non-fatal outdoor falls and road traffic injuries among children and adolescents in China: a time-stratified case-crossover study

Although studies have suggested that non-optimal temperatures may increase the risk of injury, epidemiological studies focusing on the association between temperature and non-fatal injury among children and adolescents are limited. Therefore, we investigated the short-term effect of ambient temperature on non-fatal falls and road traffic injuries (RTIs) among students across Jiangsu Province, China. Meteorological data and records of non-fatal outdoor injuries due to falls and RTIs among students aged 6-17 were collected during 2018-2020. We performed a time-stratified case-crossover analysis with a distributed lag nonlinear model to examine the effect of ambient temperature on the risk of injury. Individual meteorological exposure was estimated based on the address of the selected school. We also performed stratified analyses by sex, age, and area. A total of 57322 and 5455 cases of falls and RTIs were collected, respectively. We observed inverted U-shaped curves for temperature-injury associations, with maximum risk temperatures at 18 °C (48th of daily mean temperature distribution) for falls and 22 °C (67th of daily mean temperature distribution) for RTIs. The corresponding odds ratios (95% confidence intervals) were 2.193 (2.011, 2.391) and 3.038 (1.988, 4.644) for falls and RTIs, respectively. Notably, there was a significant age-dependent trend in which the temperature effect on falls was greater in older students (P-trend < 0.05). This study suggests a significant association between ambient temperature and students' outdoor falls and RTIs. Our findings may help advance tailored strategies to reduce the incidence of outdoor falls and RTIs in children and adolescents.

ELECTRONIC SUPPLEMENTARY MATERIAL

Supplementary material is available in the online version of this article at 10.1007/s11783-023-1705-1 and is accessible for authorized users.

The risk of injuries during work and its association with precipitation: New insight from a sentinel-based surveillance and a case-crossover design

Background

Injuries during work are often exogenous and can be easily influenced by environmental factors, especially weather conditions. Precipitation, a crucial weather factor, has been linked to unintentional injuries, yet evidence of its effect on work-related injuries is limited. Therefore, we aimed to clarify the impact of precipitation on injuries during work as well as its variation across numerous vulnerability features.

Methods

Records on the work-related injury during 2016-2020 were obtained from four sentinel hospitals in Guangzhou, China, and were matched with the daily weather data during the same period. We applied a time-stratified case-crossover design followed by a conditional logistic regression to evaluate the association between precipitation and work-related injuries. Covariates included wind speed, sunlight, temperature, SO ₂, NO ₂, and PM _2.5. Results were also stratified by multiple factors to identify the most vulnerable subgroups.

Results

Daily precipitation was a positive predictor of work-related injuries, with each 10 mm increase in precipitation being associated with an increase of 1.57% in the rate of injuries on the same day and 1.47-1.14% increase of injuries on subsequent 3 days. The results revealed that precipitation had a higher effect on work-related injuries in winter (4.92%; 95%CI: 1.77-8.17%). The elderly (2.07%; 95%CI: 0.64-3.51%), male (1.81%; 95%CI: 0.96-2.66%) workers or those with lower educational levels (2.58%; 95%CI: 1.59-3.54%) were more likely to suffer from injuries on rainy days. There was a higher risk for work-related injuries caused by falls (2.63%; 95%CI: 0.78-4.52%) or the use of glass products (1.75%; 95%CI: 0.49-3.02%) on rainy days.

Conclusions

Precipitation was a prominent risk factor for work-related injury, and its adverse effect might endure for 3 days. Certain sub-groups of workers were more vulnerable to injuries in the rain.

The relationship between ambient temperatures and road traffic injuries: a systematic review and meta-analysis

Traffic accidents cause considerable economic losses and injuries. Although the adverse effects of a change in ambient temperatures on human health have been widely documented, its effects on road traffic safety are still debated. This systematic review and meta-analysis was performed to synthesize available data on the association between ambient temperature and the risks of road traffic accidents (RTAs) and traffic accident injuries (TAIs). We searched 7 different databases to locate studies. The subgroup analyses were stratified by temperature type, temperature exposure, region, mean temperature, mortality, study period, statistical model, and source of injury data. This study was registered with PROSPERO under the number CRD42021264660. This is the first meta-analysis to investigate the association between ambient temperature and road traffic safety. A total of 34 high-temperature effect estimates were reported, and two additional studies reported the relationship between low temperatures and TAI risk. The meta-analysis results found a significant association between the high temperature and RTAs, and the pooled RR was 1.025 (95%CI 1.014, 1.035). The risk of TAI was also significantly associated with temperature increases. Subgroup analyses found that using daily mean temperatures, the RR value of road traffic accidents was 1.024 (95%CI 0.939, 1.116), and the RR value of road traffic injuries was 1.052 (95%CI 1.024, 1.080). Hourly temperatures significantly increased the risk of RTA, while the risk of TAI was not significantly increased by hourly temperature. The sensitivity analysis indicated that the results were stable, and no obvious publication bias was detected. The results of this systematic review and meta-analysis suggest that increases in ambient temperature are associated with an increased risk of RTAs and TAIs. These findings add to the evidence of the impact of ambient temperature on road traffic safety.

Effect of weather variables on the incidence of trauma: A retrospective study at a single tertiary hospital center for 4 years

The occurrence of trauma is associated with various factors, including weather. We aimed to elucidate the relationship between local weather factors and the incidence of trauma to effectively manage and treat patients in a community setting. A retrospective study was conducted at a single center from January 2016 to December 2019. The study participants were trauma patients in the Cheongju area where the regional trauma center is located. Weather data including average daily temperature (°C), rainfall duration (hours), amount of rainfall (mm), average relative humidity (%), wind speed (m/s), and total sunlight hours per day were collected. One-way analysis of variance, correlation analysis, and linear regression analysis were performed. The average age of the participants (n = 3352) was 52.69 years. As regards seasonal difference in the incidence of trauma, there were more patients in spring than in winter (2.42/day vs 2.06/day, P = .05). The highest number of average daily trauma incidents occurred from April to June, and the difference between this value and that from January to February was significant (F = 2.20, P = .01). According to the distributed lag nonlinear model (DLnM), the relative risk is greater than 1 when the mean temperature is high (>15°C) compared to when the temperature is low (<15°C). The trauma patient prevalence was the highest at high wind speed (4.5 m/s). When the total amount of sunlight was long (>Ref. 8 hours), the trauma patient prevalence was relatively higher than the median value (lag = 0). DLnM analysis results showed that the relative risk of trauma patients increased as the amount of precipitation increased, and the incidence of trauma increased when the relative humidity was 40% to 50%. Multiple linear regression analysis revealed that high average daily temperatures and long average daily total sunlight hours resulted in an increased incidence of trauma (F = 6.605, P < .001). An increase in temperature, an increase in the daily sunlight hours, an increase in rainfall, high wind speed, and relative humidity of 40% to 50% are associated with a relatively high risk of trauma.

National temporal variation in major trauma in England, Wales and Northern Ireland

Introduction

Trauma is one of the leading causes of mortality worldwide, but little is known of the temporal variation in major trauma across England, Wales and Northern Ireland. Proper workforce and infrastructure planning requires identification of the caseload burden and its temporal variation.

Materials and Methods

The Trauma Audit Research Network (TARN) database for admissions attending Major Trauma Centres (MTCs) between 1st April 2011 and 31st March 2018 was analysed. TARN records data on all trauma patients admitted to hospital who are alive at the time of admission to hospital. Major trauma was classified as an Injury Severity Score (ISS) >15.

Results

A total of 158,440 cases were analysed. Case ascertainment was over 95% for 2013 onwards. There was a statistically significant variation in caseload by year (p < 0.0001), times of admissions (p < 0.0001), caseload admitted during weekends vs weekdays, 53% vs 47% (p < 0.0001), caseload by season with most patients admitted during summer (p < 0.0001). The ISS varied by time of admission with most patients admitted between 1800 and 0559 (p < 0.0001), weekend vs weekday with more severely injured patients admitted during the weekend (p < 0.0001) and by season p < 0.0001). Discussion and Conclusion: There is a significant national temporal variation in major trauma workload. The reasons are complex and there are multiple theories and confounding factors to explain it. This is the largest dataset for hospitals submitting to TARN which can help guide workforce and resource allocation to further improve trauma outcomes.

The influence of foehn winds on the incidence of severe injuries in southern Bavaria - an analysis of the TraumaRegister DGU®

Background

Foehn describes a wind which occurs in areas with close proximity to mountains. The presence of foehn wind is associated with worsening health conditions.

This study analyzes the correlation between a foehn typical circulation and the incidence for suffering a severe trauma.

Methods

This is a retrospective, multicentre observational register study. The years from 2013 to 2016 were analyzed for the presence of foehn winds. A logistic regression analysis with the number of daily admitted trauma patients as the primary target value was performed in dependence of foehn winds.

Southern Bavaria is a typical foehn wind region. Individuals were treated in 37 hospitals of Southern Bavaria which participate in the TraumaRegister DGU®, an international register that includes all severe trauma patients, mainly in Germany.

We analyzed patients with an Injury Severity Score (ISS) of at least nine with admission to intensive care units or prior death in the emergency room.

Results

6215 patients were enrolled in this study. A foehn-typical circulation was present on 65 days (4.5%). 301 patients (5%) suffered a trauma with an ISS ≥ 9 on a foehn day. The mean ISS was 20.2 (9–75). On average, 4.3 patients (0–15 patients) were admitted on a daily basis due to a severe trauma.

The multivariate regression analysis revealed a daily increase of 0.87 individuals (p = 0.004; 95% CI 0.23–1.47) on foehn days. During spring 1.07 patients (p = < 0.001; 95% CI 0.72–1.42), in summer 1.98 patients (p = < 0.001; 95% CI 1.63–2.32), in fall 0.63 (p = < 0.001; 95% CI 0.28–0.97) and on Saturdays, 0.59 patients (p = < 0.001; 95% CI 0.24–0.93) were additionally admitted due to severe trauma.

Conclusion

Foehn winds are significantly associated with severe trauma in trauma centers of the TraumaNetzwerk DGU®.

The association between meteorological variables and road traffic injuries: a study from Macao

Objective

Correlation analysis and multiple linear regression analysis were conducted to estimate the influence of meteorological factors on road traffic injuries stratified by severity. Crash rate was defined as mean monthly road traffic accidents per 1,000 vectors.

Design

Ecological time-series study.

Setting

Macao traffic accident registry database between January 1st, 2001 and November 31st, 2016.

Participants

In total, 393,176 traffic accidents and 72,501 cases of road traffic injuries (RTIs) were enrolled; patients’ severity was divided into mild injury, required hospitalisation, and death.

Exposure

Variation of monthly meteorological factors.

Main outcome measure

Weather-condition-related road traffic accidents, injuries, and deaths.

Results

Windy weather significantly correlated with increased number of traffic accidents among all transport vectors (r = .375 to .637; p < 0.001). Multiple linear regression showed temperature (B = 0.704; p < 0.05) and humidity (B =  − 0.537; p < 0.001) were independent factors for mild injury. The role of windy weather was relatively more obvious among patients with severe injuries (B = 0.304; p < 0.001) or those who died (B = 0.015; p < 0.001). A longer duration of sunshine was also associated to RTI-related deaths (B = 0.015; p < 0.001). In total, 13.4% of RTIs were attributable to meteorological factors and may be preventable.

Conclusion

The World Health Organization stated that RTIs are a major but neglected public health challenge. This study demonstrates meteorological factors have significant effects on any degree of RTIs. The results may not be generalized to other climates or populations while the findings may have implications in both preventing injuries and to announce safety precautions regarding trauma and motor vehicle collisions to the general public by public agencies.

[Effect of City-Specific Characteristics on Association between Heat and Ambulance Dispatches]

OBJECTIVES

In this multicity study, we aimed to elucidate the city-specific factors affecting the association of high ambient temperature with ambulance dispatches due to acute illnesses.

METHODS

We used the data of ambulance dispatches in 27 cities in Japan with more than 500,000 population excluding Tokyo, from May to September from 2012 to 2015. We included patients 20 years and older (≥20 years) and stratified them into three age groups (20-59, 60-79, and ≥80 years). We explored the city-specific pattern of the daily relative temperature (in temperature percentiles) and the risk of ambulance dispatches for each age group using a distributed lag nonlinear model and estimated the city-specific relative risks of ambulance dispatches at the 95/99 percentile temperature compared with the 77.6 percentile temperature defined as the reference temperature (Tref). Then, the estimates were combined by performing meta-analyses for each age group. We also applied meta-regression models to explore whether the city-specific characteristics modified the association of temperature with ambulance dispatches.

RESULTS

The relative risks of the 95th percentile with respect to Tref were 1.14 (95% confidence interval (CI): 1.12, 1.16), 1.16 (95% CI: 1.13, 1.20), 1.13 (95% CI: 1.10, 1.16), and 1.13 (95% CI: 1.00, 1.16), for all-age (≥20) and age-stratified groups (20-59, 60-79, and ≥80 years), respectively. We observed a higher relative risk for the ≥20 years age group in the cities with higher proportions of single-elderly, single-mother, and single-father households. We also found that the relative risk for the 20-59 years age group was higher in the cities with a higher proportion of blue-collar workers.

CONCLUSIONS

The present study provides insights into city-specific characteristics modifying heat-related health effects.

Seasonal Variation of Trauma in Western Massachusetts: Fact or Folklore?

Background

Previous studies have demonstrated a significant relationship between weather or seasons and total trauma admissions. We hypothesized that specific mechanisms such as penetrating trauma, motor vehicle crashes, and motorcycle crashes (MCCs) occur more commonly during the summer, while more falls and suicide attempts during winter.

Methods

A retrospective review of trauma admissions to a single Level I trauma center in Springfield, Massachusetts from 01/2010 through 12/2015 was performed. Basic demographics including age, Injury Severity Score (ISS), and length of stay were collected. Linear regression analysis was used to test the association between monthly admission rates and season, year, injury class, and mechanism of injury, and whether seasonal variation trends were different according to injury class or mechanism.

Results

A total of 8886 admissions had a mean age of 44.6 and mean ISS of 11.9. Regression analysis showed significant seasonal variation in blunt compared with penetrating trauma (p<0.001), MCC (p<0.001), and falls (p=0.002). In addition, seasonal variation differed according to injury class or mechanism. There were significantly lower rates of MCCs in winter compared with all other seasons and conversely higher rates of total falls in winter compared with other seasons.

Discussion

A significant seasonal variation in blunt trauma, MCC, and falls was observed. This has potential ramifications for resource allocation, including trauma prevention programs geared toward mechanisms of injury with significant seasonal variation.

Level of evidence

Retrospective Review, Level IV.

Temporal variation in major trauma admissions

INTRODUCTION

Trauma is a significant cause of morbidity and mortality in the UK. Since the inception of the trauma networks, little is known of the temporal pattern of trauma admissions.

METHODS

Trauma Audit and Research Network data for 1 April 2011 to 31 March 2013 were collated from two large major trauma centres (MTCs) in the South East of England: Brighton and Sussex University Hospitals NHS Trust (BSUH) and St George's University Hospitals NHS Foundation Trust (SGU). The number of admissions and the injury severity score by time of admission, by weekdays versus weekend and by month/season were analysed.

RESULTS

There were 1,223 admissions at BSUH and 1,241 at SGU. There was significant variation by time of admission; there were more admissions in the afternoons (BSUH p<0.001) and evenings (SGU p<0.001). There were proportionally more admissions at the weekends than on weekdays (BSUH p<0.001, SGU p=0.028). There was significant seasonal variation in admissions at BSUH (p<0.001) with more admissions in summer and autumn. No significant seasonal variation was observed at SGU (p=0.543).

CONCLUSIONS

The temporal patterns observed were different for each MTC with important implications for resource planning of trauma care. This study identified differing needs for different MTCs and resource planning should be individualised to the network.

Investigating the relationship between weather and violence in Baltimore, Maryland, USA

BACKGROUND

It is a common refrain at major urban trauma centers that caseloads increase in the heat of the summer. Several previous studies supported this assertion, finding trauma admissions and crime to correlate positively with temperature. We examined links between weather and violence in Baltimore, MD, through trauma presentation to Johns Hopkins Hospital and crime reports filed with the Baltimore Police Department.

METHODS

Crime data were obtained from the Baltimore City Police Department from January 1, 2008 to March 31, 2013. Trauma data were obtained from a prospectively collected registry of all trauma patients presenting to Johns Hopkins Hospital from January 1, 2007 to March 31, 2013. Weather data were obtained from the National Climatic Data Center. Correlation coefficients were calculated and negative binomial regression was used to elucidate the independent associations of weather and temporal variables with the trauma and crime data.

RESULTS

When adjusting for temporal and meteorological factors, maximum daily temperature was positively associated with total trauma, intentional injury, and gunshot wounds presenting to Johns Hopkins Hospital along with total crime, violent crime, and homicides in Baltimore City. Associations of average wind speed, daily precipitation, and daily snowfall with trauma and crime were far weaker and, when significant, nearly universally negative.

CONCLUSION

Maximum daily temperature is the most important weather factor associated with violence and trauma in our study period and location. Our findings suggest potential implications for hospital staffing to be explored in future studies.

Effect of weather and time on trauma events determined using emergency medical service registry data

INTRODUCTION

Trauma admissions are associated with weather and temporal factors; however, previous study results regarding these factors are contradictory. We hypothesised that weather and temporal factors have different effects on specific trauma events in an emergency medical service (EMS) system.

METHODS

EMS data from January 1, 2009, to December 31, 2010, were obtained from the fire department of Taipei City and associated with the local weather data. EMS trauma events were categorised into total trauma, traffic accidents (TAs), motorbike accidents (MBAs), and falls. Hourly data on trauma patients were analysed using the zero-inflated Poisson model.

RESULTS

The hourly incidence of total trauma increased with the magnitude of precipitation (incidence rate ratio [IRR]=1.06, 1.09, and 1.11 in light, moderate, and heavy rain, respectively), and this effect was more prominent in fall patients than in patients with other injuries (IRR=1.07, 1.21, and 1.32). However, the hourly incidence of TAs and MBAs was associated only with light rain (IRR=1.11 and 1.06, respectively). An hour of sunshine exposure was associated with an increase in the hourly incidence of all groups, and higher temperatures were associated with an increased hourly incidence of total trauma, TAs, and MBAs, but not falls. The hourly incidence of falls increased only in late fall and winter. Compared with the hourly incidence between 3 am and 7 am, the hourly incidence of all groups plateaued between 7 am and 11 pm and declined from 11 pm to 3 am. During the plateau period, 2 peaks in the incidence of TAs (IRR=5.03 and 5.07, respectively) and MBAs (IRR=5.81 and 5.51, respectively) were observed during 7-11 am and 3-7 pm. The hourly incidence of total trauma, TAs, and MBAs plateaued during workdays, peaked on Fridays, declined on Saturdays, and troughed on Sundays. The incidence of falls increased only on Mondays (IRR=1.09).

CONCLUSIONS

Weather and temporal factors had different impacts on the incidence of traffic-related accidents and falls. Therefore, EMS data may have implications in preventing injuries and planning resource use for prehospital trauma rescue.

What is the effect of the weather on trauma workload? A systematic review of the literature

BACKGROUND

Hospital admission rates for a number of conditions have been linked to variations in the weather. It is well established that trauma workload displays significant seasonal variation. A reliable predictive model might enable targeting of high-risk groups for intervention and planning of hospital staff levels. To our knowledge there have been no systematic reviews of the literature on the relationship between weather and trauma workload, and predictive models have thus far been informed by the results of single studies.

METHODS

We conducted a systematic review of bibliographic databases and reference lists up to June 2014 to identify primary research papers assessing the effect of specified weather conditions including temperature, rainfall, snow, fog, hail, humidity and wind speed on trauma workload, defined as admission to hospital, fracture or a Road Traffic Accident (RTA) resulting in a seriously injured casualty or fatality.

RESULTS

11,083 papers were found through electronic and reference search. 83 full papers were assessed for eligibility. 28 met inclusion criteria and were included in the final review; 6 of these related to the effect of the weather on trauma admissions, one to ambulance call out for trauma, 13 to fracture rate and 8 to RTAs. Increased temperature is positively correlated with trauma admissions. The rate of distal radius fractures is more sensitive to adverse weather than the rate of hip fractures. Paediatric trauma, both in respect of trauma admissions and fracture rate, is more sensitive to the weather than adult trauma. Adverse weather influences both RTA frequency and severity, but the nature of the relationship is dependent upon the timecourse of the weather event and the population studied. Important methodological differences between studies limit the value of the existing literature in building consensus for a generalisable predictive model.

CONCLUSIONS

Weather conditions may have a substantial effect on trauma workload independent of the effects of seasonal variation; the population studied and timecourse of weather events appear critical in determining this relationship. Methodological differences between studies limit the validity of conclusions drawn from analysis of the literature, and we identify a number of areas that future research might address.

A time series study on the effects of cold temperature on road traffic injuries in Seoul, Korea

OBJECTIVE

Although traffic accidents are associated with weather, the influence of temperature on injuries from traffic accidents has not been evaluated sufficiently. The objective of this study was to evaluate the effect of temperature, especially cold temperatures, on injuries from traffic accidents in Seoul, Korea. We also explored the relationship of temperature with different types of traffic accident.

METHODS

The daily frequencies of injuries from traffic accidents in Seoul were summarized from the integrated database established by the Korea Road Traffic Authority. Weather data included temperature, barometric pressure, rainfall, snow, and fog from May 2007 to December 2011. The qualitative relationship between daily mean temperature and injuries from traffic accidents was evaluated using a generalized additive model with Poisson distribution. Further analysis was performed using piecewise linear regression if graph the showed non-linearity with threshold.

RESULTS

The incidence of injuries was 216 per 100,000 person-months in Seoul. The effect of temperature on injuries from traffic accidents was minimal during spring and summer. However, injuries showed a more striking relationship with temperature in winter than in other seasons. In winter, the number of injuries increased as the temperature decreased to <0°C. The injuries increased by 2.1% per 1°C decrease under the threshold of the daily average temperature -5.7°C, which is 10-fold greater than the effect of temperature above the threshold. Some groups were more susceptible to injuries, such as young and male drivers, according to the types of traffic accident when the temperature decreased to below the freezing temperature.

CONCLUSIONS

The incidence of injuries increased sharply when the temperature decreased below freezing temperature in winter. Temperature can be effectively used to inform high risk of road traffic injuries, thus helping to prevent road traffic injuries.

Association between temperature and emergency room visits for cardiorespiratory diseases, metabolic syndrome-related diseases, and accidents in metropolitan Taipei

OBJECTIVE

This study evaluated risks of the emergency room visits (ERV) for cerebrovascular diseases, heart diseases, ischemic heart disease, hypertensive diseases, chronic renal failure (CRF), diabetes mellitus (DM), asthma, chronic airway obstruction not elsewhere classified (CAO), and accidents associated with the ambient temperature from 2000 to 2009 in metropolitan Taipei.

METHODS

The distributed lag non-linear model was used to estimate the cumulative relative risk (RR) and confidence interval (CI) of cause-specific ERV associated with daily temperature from lag 0 to lag 3 after controlling for potential confounders.

RESULTS

This study identified that temperatures related to the lowest risk of ERV was 26 °C for cerebrovascular diseases, 18 °C for CRF, DM, and accidents, and 30 °C for hypertensive diseases, asthma, and CAO. These temperatures were used as the reference temperatures to measure RR for the corresponding diseases. A low temperature (14°C) increased the ERV risk for cerebrovascular diseases, hypertensive diseases, and asthma, with respective cumulative 4-day RRs of 1.56 (95% CI: 1.23, 1.97), 1.78 (95% CI: 1.37, 2.34), and 2.93 (95% CI: 1.26, 6.79). The effects were greater on, or after, lag one. At 32°C, the cumulative 4-day RR for ERV was significant for CRF (RR = 2.36; 95% CI: 1.33, 4.19) and accidents (RR = 1.23; 95% CI: 1.14, 1.33) and the highest RR was seen on lag 0 for CRF (RR = 1.69; 95% CI: 1.01, 3.58), DM (RR = 1.69; 95% CI: 1.09, 2.61), and accidents (RR = 1.19; 95% CI: 1.11, 1.27).

CONCLUSIONS

Higher temperatures are associated with the increased ERV risks for CRF, DM, and accidents and lower temperatures with the increased ERV risks for cerebrovascular diseases, hypertensive diseases, and asthma in the subtropical metropolitan.

Descriptive analysis of patients' EMS use related to severity in Tokyo: a population-based observational study

Introduction

Few studies are available on the clinical characteristics of patients using emergency medical transports in Japan. In this study, we aimed to investigate reasons for emergency medical transports and their relation to clinical severity.

Methods

We conducted a 3-year population-based observational study of patients transported by ambulance to emergency departments (ED) in the capital of Japan, Tokyo, which has a population of about 13 million. Demographic data, reasons for transport, and the severity of initial assessment at ED were recorded. Logistic regression was used to determine the odds of the clinical severity of each reason for transport.

Results

The number of emergency medical transports in the three-year study period was 1,832,637. Mean age was 53±26. Males were 976,142 (53%). Overall, 92% of all transported patients were in a mild or moderate medical state and patients with the 17 most frequent reasons for transport occupied 82% (1,506,017) of all transports. Pain was the most frequent reason for transport, followed by traffic accident. Considering all the patients and their reasons for transport, patients whose reason was pain or a traffic accident (29% of all patients) were in a relatively mild state compared with patients with other reasons for transport. Patients in an altered mental state in the prehospital setting (6.8% of all patients) were in a more severe medical state than other patients.

Conclusions

In Tokyo, Japan, 92% of transported patients were in a mild or moderate medical state. In particular, most patients from traffic accidents were in a mild state, even though traffic accidents were the second most frequent reason for transport. Patients in an altered mental state were most likely to be in a severe medical state.

Different influence of outdoor temperature on traumatic and nontraumatic injuries

BACKGROUND

Injuries are affected by weather conditions, which influence various human activities. However, only a few studies have reported an association between injuries and weather conditions despite the fact that extreme weather conditions can occur more frequently with climate change. The goal of this study was to evaluate the association between outdoor temperature and traumatic and nontraumatic injury using emergency ambulance delivery.

METHODS

We designed a prognostic study to evaluate the different effects of outdoor temperature depending on types of injury. Using a generalized additive model, we examined the association between outdoor temperatures and injuries in Korea from 2006 to 2008, adjusting for confounders such as relative humidity, day of the week, and long-term time trends. A random effects model was used to estimate combined effects across all areas.

RESULTS

The city-combined effect estimate for nontraumatic injuries was 1.95% (95% confidence interval, 1.28-2.62%) corresponding to a 1°C increase in mean temperature, whereas the relationship for traumatic injuries was not linear. The risk of nontraumatic injury related to temperature for males and elderly individuals was higher than for females and younger people.

CONCLUSION

The risk of injury attributable to outdoor temperature was found to vary according to the injury type. This information may be useful for developing adaptation strategies related to climate change.

LEVEL OF EVIDENCE

Prognostic study, level III.

Long-term prediction of emergency department revenue and visitor volume using autoregressive integrated moving average model

This study analyzed meteorological, clinical and economic factors in terms of their effects on monthly ED revenue and visitor volume. Monthly data from January 1, 2005 to September 30, 2009 were analyzed. Spearman correlation and cross-correlation analyses were performed to identify the correlation between each independent variable, ED revenue, and visitor volume. Autoregressive integrated moving average (ARIMA) model was used to quantify the relationship between each independent variable, ED revenue, and visitor volume. The accuracies were evaluated by comparing model forecasts to actual values with mean absolute percentage of error. Sensitivity of prediction errors to model training time was also evaluated. The ARIMA models indicated that mean maximum temperature, relative humidity, rainfall, non-trauma, and trauma visits may correlate positively with ED revenue, but mean minimum temperature may correlate negatively with ED revenue. Moreover, mean minimum temperature and stock market index fluctuation may correlate positively with trauma visitor volume. Mean maximum temperature, relative humidity and stock market index fluctuation may correlate positively with non-trauma visitor volume. Mean maximum temperature and relative humidity may correlate positively with pediatric visitor volume, but mean minimum temperature may correlate negatively with pediatric visitor volume. The model also performed well in forecasting revenue and visitor volume.

High temperature effects on out-patient visits and hospital admissions in Chiang Mai, Thailand

OBJECTIVES

This study investigated the short-term effects of temperature on out-patient visits and hospital admissions in Chiang Mai, Thailand. While mortality outcomes in the literature have been reported, there is less evidence of morbidity effects with very few studies conducted in developing countries with subtropical or tropical climate.

METHODS

Time-series regression analysis was employed using generalized negative binomial regression to model the short-term relationships between temperature and morbidity after controlling for seasonal patterns and other potential confounders. Lag effects up to 13 days and effect modification by age (0-14 years, 15-64 years, ≥65 years) were examined.

RESULTS

Temperature effects with wide confidence intervals were found, with an increase in diabetic visits of 26.3% (95% CI: 7.1%-49.0%), and circulatory visits of 19.2% (95% CI: 7.0%-32.8%) per 1 °C increase in temperature above an identified threshold of 29 °C. Additionally, there was a rise of both visits (3.7% increase, 95% CI: 1.5%-5.9%) and admissions (5.8% increase, 95% CI: 2.3%-9.3%) due to intestinal infectious disease in association with each 1 °C increase across the whole temperature range. The effects of temperature were stronger in the elderly though not statistically significant.

CONCLUSIONS

Daily morbidity in Chiang Mai was positively associated with temperature with a lag effect of up to 2 weeks, which was longer than lag effects previously reported. Public health preparedness and interventions should be considered to minimise possible increased hospital visits and admissions during hot weather.