Investigation of the effect of air pollution levels on hospital admissions caused by respiratory diseases in an industrial city for the years 2016-2020 with case crossover study design

In this study, hospital admissions due to respiratory system diseases in an industrial city, some characteristics of air pollution and meteorological data, and the effects of air pollutant levels on hospital admissions were investigated. The research is an observational ecological study and a case crossover design was used in the study. The data were obtained by obtaining permission from the relevant units. Annual averages of air pollutant levels of 3 air quality monitoring stations measuring in the province were found above the limit values in the vast majority. In the correlation analysis between the meteorological and air pollution data, a statistically significant relationship was found between the parameters at different levels. In the first part of the study, 8224 hospital admissions were included. İn the second part of the case crossover method analysis, 7065 admissions were included in the conditional logistic regression model. %73.8 of the total 8224 admissions for 5 years were due to Asthma and %26.2 to COPD. %68.8 of total admissions for asthma are women, %74.8 of total admissions for COPD are men. A statistically significant relationship found between admissions according to diseases and age and gender. According to the results of conditional logistic regression analysis; a statistically significant relationship not found between each 10μg/m³ increase in 2-day lag of PM₁₀ concentrations and 5year total Asthma and COPD admissions. An increase of 10µg/m³ in PM₁₀ levels in the 2-day lag period in the hot season decreased by 0.66 times COPD admissions was found statistically significant. When the 2020 pandemic year was excluded from the model, a statistically significant relationship was found between each 10 µg/m³ increase in 2-day lag of PM₁₀ level and the COPD admissions. It was found that exposure to a 10 µg/m³ increase in PM₁₀ level increased COPD admissions 1.22 times. There is no significant relationship was found between PM₁₀ levels and Asthma admissions. Key words: Air pollution, Asthma, COPD, Case-crossover, Hospital admissions