Impact of Ambient Air Pollution and Meteorological Factors on Hospital Admission to the Cardiovascular System Disease on Ulaanbaatar City of Mongolia

Background: Mongolia is situated in northern Central Asia. Landlocked between China and Russia, it is a vast expanse of high attitude grassland steppe, desert, and mountain covering an area of 1,565,000 square kilometers. Air pollution is an increasingly series problem in Mongolia. Materials and Methods: This is a time-series cross over study. All health and air pollution data of 2008-2017 was used for this survey. Results: The mean level of SO2 during the cold season was 35.22 μg/m3 and during the warm season it was 4.65 μg/m3. 24 hours PM10 concentration, during the cold season daily average concentration was 226.77 μg/m3. The 8 hours average daily carbon monoxide concentration (1352.85 μg/m3 [95% CI: 1313.07 - 1396.15]) was high during the cold season, ozone concentration (39.10 μg/m3 [95% CI: 37.95 - 40.35]) was high during the warm season. Air quality depends on metrological parameters. All correlation was statistically significant during the whole year and cold season. In total, 288,832 people get admitted to the hospital due to cardiovascular system disease in Ulaanbaatar during the year of 2008-2017. In general, hospitalization is increasing year by year. Significant associations were found for SO2 with hypertensive diseases (I10 - I15), ischemic heart diseases (I20 - I25), cerebrovascular diseases (I60 - I69), diseases of pulmonary circulation and other forms of heart (I00 - I09, I26 - I52) in all lags. For NO2 was less associated with Ischemic heart diseases (I20 - I25) and diseases of pulmonary circulation and other forms of heart (I00 - I09, I26 - I52). For both PM10 and PM2.5, every disease had observed significant RR in lag 0 - 3. Significant associations were found for air pollutants such as PM10, PM2.5, CO, SO2, and O3 in all lags had a statistically significant association with cold season’s cardiovascular system disease admission. As expected during the warm season significant association was found only lag 1 with PM2.5 and lags (0, 1) CO and O3. Conclusion: As expected this study demonstrated significant correlations between cardiovascular morbidity with PM2.5, PM10, NO2, SO2, CO, O3, and some meteorological parameters.