| Objective:To analyze the changes of air quality,meteorological factors and the number of hospitalizations for cardiovascular diseases in Urumqi,to quantitatively assess the lagged and cumulative effects of atmospheric pollutants on the number of daily hospitalizations for cardiovascular diseases,to explore the effects of meteorological factors on the number of hospitalizations for cardiovascular diseases,and to provide scientific guidance for the prevention and control of cardiovascular diseases in hospitals in the region.Methods:In this study,daily data on air pollutants and meteorological factors were collected from January 1,2019 to December 31,2021 in Urumqi city.Air pollutants included fine particulate matter,respirable particulate matter,sulfur dioxide,nitrogen dioxide,carbon monoxide,and ozone,and meteorological factors included daily average temperature,relative humidity,daily average air pressure,daily average wind speed,and diurnal temperature difference to describe the temporal distribution of air pollutants and meteorological factors and changes in air quality index.Correlation between atmospheric pollutants and meteorological factors in Urumqi city was analyzed using Spearman correlation.Daily hospitalization data for cardiovascular diseases were collected from three tertiary and four secondary hospitals in Urumqi from 2019 to 2021,and a distribution lagged nonlinear model was used to study the effect of atmospheric pollutants on the number of hospitalizations for cardiovascular diseases,using the relative risk and 95%confidence interval of each 10μg/cm3 increase in pollutants on hospitalizations for cardiovascular diseases,as well as by age and The analysis was stratified by age and gender.We analyzed the effects of different meteorological factors（diurnal temperature difference,relative humidity and mean air pressure）on the number of daily hospitalizations for cardiovascular and cerebrovascular diseases and their lagged effects by establishing a"cross-based"function of lag time and meteorological factors,and evaluated the effects of meteorological factors on the number of hospitalizations for cardiovascular and cerebrovascular diseases.Results:1.The total number of days with good air quality in Urumqi from 2019 to 2021 is695,accounting for more than half of the total number of days.AQI,PM2.5,PM10,SO2,NO2,CO all show seasonal trends of high in winter and spring,low in summer and autumn,and O3 shows the opposite trend.The meteorological factors all show seasonal fluctuations.2.The total number of hospitalizations for cardiovascular and cerebrovascular diseases was99,018,with an average daily occurrence of 90 cases,a male to female ratio of 0.96:1,and a ratio of 1:1.13 for young（<65 years old）to old（≥65 years old）.3.PM2.5,PM10,SO2,NO2,and CO were positively correlated with each other,and O3was negatively correlated with other pollutants,relative humidity,and daily average air pressure,and all indicators were statistically significant（P<0.05）,except for the diurnal temperature difference,which was not correlated with PM10 and SO2.4.under the single pollutant model,the maximum effect value was 1.025（95%CI:1.009,1.041）for each 10μg/m3 increase in PM2.5 concentration at a 7-day lag.the relative risk of PM10 at a 1-day lag was 1.005（95%CI:1.000,1.009）.There was no immediate risk effect of NO2 on cardiovascular disease hospitalizations.There was a cumulative lagged effect of CO on cardiovascular disease hospitalizations.There was no significant effect of SO2and O3 on cardiovascular disease hospitalizations.PM2.5,PM10,SO2,and CO have greater risk effects on men and young adults than on women and older adults 5.The exposure-response curve of the effect of diurnal temperature difference on hospitalization for cardiovascular diseases was approximately"J"shaped,and the higher the diurnal temperature difference,the stronger the effect on hospitalization for cardiovascular diseases.Men and the elderly were more sensitive to high diurnal temperature differences.There was no immediate effect of high relative humidity on the relative risk of hospitalization for cardiovascular disease.The maximum relative risk at a lag of 4 days was 1.170（95%CI:1.057,1.294）when the relative humidity was 98%.Women and the elderly were more sensitive to high relative humidity.The maximum 1-day lagged risk effect was 1.514（95%CI:1.205,1.902）when the mean air pressure was 932 hpa.Males were more sensitive to high mean air pressure.Conclusion:From 2019 to 2021,the air quality of Urumqi city was improved year by year,except for O3,the air pollutants showed the pollution characteristics of high in winter and spring,low in summer and autumn,and the air pollutants and meteorological factors showed certain seasonal and cyclical trends.PM2.5 had the strongest effect on the risk of cardiovascular and cerebrovascular disease hospitalization,and O3 and SO2 had no significant effect.The lagged effects of PM2.5,PM10,SO2 and CO on cardiovascular disease hospitalization were greater in males and young adults than in females and older adults.Males and older adults were more sensitive to high diurnal temperature differences;females and older adults were more sensitive to high relative humidity;and males were more sensitive to high mean air pressure. |
