Ambulance Services Associated with Extreme Temperatures and Fine Particles in a Subtropical Island

Yu-Chun Wang,Yasmin Zafirah,Yi-Jhih Chen,Fung-Chang Sung,Yu-Kai Lin,Shih-Chan Hung

doi:10.1038/s41598-020-59294-8

Abstract

This study evaluated the association between the risk of events requiring ambulance services and the ambient temperature and particulate matter of 2.5 μm (PM2.5) and 10 μm (PM10) for populations living in subtropical Taiwan. We used a distributed lag nonlinear model with a quasi-Poisson function to assess the roles of ambient temperature, PM10 and PM2.5 in the use of ambulance services for respiratory distress, coma and unconsciousness, chest pain, lying down in public, headaches/dizziness/vertigo/fainting/syncope and out-of-hospital cardiac arrest (OHCA). The relative risk (RR) and 95% confidence interval (CI) of each specific event were calculated in association with the ambient conditions. In general, the events that required ambulance services had a V-shaped or J-shaped association with the temperature, where the risks were higher at extreme temperatures. The RR of each event was significant when the patients were exposed to temperatures in the 5th percentile (<15 °C); patients with OHCA had the highest adjusted RR of 1.61 (95% CI = 1.47–1.77). The risks were also significant for coma/unconsciousness, headaches/dizziness/vertigo/fainting/syncope, and OHCA but not for respiratory distress, chest pain and lying down in public, after exposure to the 99th percentile temperatures of >30 °C. The risks for use of ambulance services increased with PM exposure and were significant for events of respiratory distress, chest pain and OHCA after exposure to the 99th percentile PM2.5 after controlling for temperatures. Events requiring ambulance services were more likely to occur when the ambient temperature was low than when it was high for the population on the subtropical island of Taiwan. The association of the risk of events requiring ambulance services with PM were not as strong as the association with low temperatures.

Highlights

The increased frequency and intensity of extreme climate events are important public health concerns[1]
The present study evaluated the relationship between the use of ambulance services and the ambient temperature conditions and fine particulate matter of 2.5 μm and 10 μm (PM2.5 and PM10)
The present study showed that the relative risks of respiratory distress, chest pain, and of-hospital cardiac arrest (OHCA) among ambulance services associated with daily PM10 and PM2.5 in the 99th percentile increased after controlling for temperature (Table 3)

Summary

Introduction

The increased frequency and intensity of extreme climate events are important public health concerns[1]. Studies have reported that ambient temperature and air pollution are important factors with significant impacts associated with various morbidities and mortalities[2,3,4]. In Taiwan, the cumulative 6-day relative risk of emergency room visits for OHCA reaches 1.73 when the mean temperature is 14 °C in comparison to when it is >27 °C after controlling for air pollution[12]. Studies found that the ambulance dispatch services in Italy and Japan increased due to emergency events of OHCA, respiratory disorders and chest pain, etc., during a period with extreme temperatures[16,17]. Ambulance call-out data provide new and valuable real-time information that is useful for assessing the impacts of environmental conditions, such as temperature and air pollution, on human health[22]. The present study evaluated the relationship between the use of ambulance services and the ambient temperature conditions and fine particulate matter of 2.5 μm and 10 μm (PM2.5 and PM10)

Methods

Results

Discussion

Conclusion