WEATHER FACTORS AND AMBULANCE CALLS FOR RESPIRATORY CAUSES IN THE CITY OF PETROZAVODSK

Abstract

Aim: To study associations between selected weather factors on the number of ambulance calls for selected respiratory diseases in the city of Petrozavodsk, Northwest Russia. Methods: Data on the number of ambulance calls in the city of Petrozavodsk were obtained for the period from 2015-2017. Associations between weather factors and the number of ambulance calls for respiratory diseases were studied by correlation analysis. Pearson's correlation coefficients were calculated. Separate analyses were performed for acute upper respiratory tract infections (J06), viral pneumonia (J12), acute bronchitis (J20) and asthma (J45). An additional analysis was performed for the warm- (14 months with the mean monthly temperature from +9.8 to +18.4 °C) and the cold (22 months with a temperature from -14.9 to +5.0 °C) seasons. Results: The overall number of ambulate calls for viral pneumonia decreased during the study period. Significant associations between air temperature and atmospheric pressure and the number of calls for respiratory deceases, particularly for acute respiratory tract infections. During the cold season the influence of the temperature factor on the number of calls decreased for the most cases except acute bronchitis. The lowest number of calls for acute bronchitis was observed during summers. In summer, the number of calls for acute bronchitis was positively associated with wind speed and inversely associated with mean temperature and humidity. The number of calls for acute respiratory infections was positively associated with intraday increase in barometric pressure and wind speed. In autumn, significant correlations were observed between the North-West wind, which carries air pollutants from the industrial part of the city to the residential area and the number ambulance calls. In winter, an inverse association between humidity and ambulance calls for viral pneumonia was found. In spring, significant associations between the number of ambulance calls for several respiratory causes and cloudiness were observed. Conclusion: Significant associations between weather factors and the number of ambulance calls for respiratory causes were observed in the city of Petrozavodsk. Our results can contribute to better planning of ambulance services in town.