Effects of extreme temperatures on childhood allergic respiratory diseases with and without sensitization to house dust mites in Shanghai, China

Abstract

BackgroundThe negative impacts of environmental factors on allergic respiratory diseases (ARD) in children have gotten a lot of attention recently. However, the influence of climatic conditions, especially extreme temperatures, on childhood ARD induced by house dust mites (HDM-ARD) is uncertain. ObjectiveWe aimed to quantify the associations between outpatient visits for HDM-ARD and extreme temperatures in Shanghai, China. MethodsA distributed lag nonlinear model combined with Quasi-Poisson generalized linear model was used to analyze data. ResultsDaily mean temperature was significantly associated with outpatient visits for childhood ARD and HDM-ARD. Exposure to extreme temperatures increased the cumulative relative risks of outpatient visits for ARD and HDM-ARD in children (RRlag0–28 for the 5th percentile of Tmean: 2.97, 95% confidence interval (CI): 1.25, 7.06; RRlag0–28 for the 95th percentile of Tmean: 2.85, 95% CI: 1.03, 7.86). Boys were vulnerable to extreme lower temperature, while girls were more sensitive to extreme higher temperature in both ARD and HDM-ARD. The effect seemed to be most pronounced among 6–11 years of age school children. ConclusionOur study presents quantitative evidence that extreme temperatures prompted outpatient visits for children with ARD, especially HDM-ARD, in Shanghai, China. These findings might have significant consequences for developing appropriate preventive measures for vulnerable populations.