Environmental factors affecting seasonality of ambulance emergency service visits for exacerbations of asthma and COPD

Abstract

:Objective: The aim of this study was to assess the association of severe exacerbations of asthma and Chronic Obstructive Pulmonary Disease (COPD) requiring ambulance emergency service (AES) visits with meteorological parameters and influenza outbreaks. Methods: The records of patients calling the AES in 2007 and 2008 in the urban area of Lodz due to dyspnea were analyzed. Information on 25 daily reported meteorological parameters was obtained from the local meteorological service and data on influenza outbreaks obtained from the national surveillance service. Results: During the winter months, a significantly higher mean daily number of AES visits for both COPD and asthma were noticed when compared to the summer. Interestingly, the number of daily AES visits correlated with several weather parameters, and the multiple regression analysis confirmed a negative correlation with minimum temperature, mean temperature and the dew point for both diseases (R = 0.526; p < 0.01; R = 0.577; p < 0.01 and R = 0.589; p < 0.01). Furthermore, the increased number of AES visits also correlated with a new number of cases of influenza infections as reported by local influenza surveillance system (rs = 77.6%; p < 0.001 and rs = 80.8%; p < 0.001 for asthma and COPD, respectively). Conclusion: Seasonality of AES visits for asthma and COPD are similar and seems to be related to specific weather conditions and to influenza outbreaks.