The Effects Of Air Pollution On Daily Respiratory And Cardiovascular Diseases Hospital Admissions In Wuhan

Over the last several decades,rapid urbanization,motorization,and industrialization have led to a marked rise in air pollution,and the negative health impacts of air pollution has become one of the main factors affecting the public health.Associations between outdoor air pollution and adverse health effects for cardiovascular and respiratory disease were well documented in multiple cities at home and abroad.In general,the main method to examine the acute health effects of air pollution in the world is time series studies.This study collected the data of air pollutants（API or AQI,SO₂,NO₂,PM2.5,O₃,CO）and the meteorological data in Wuhan from 1 January,2005 to 31 December,2015 to get knowledge of the characteristics of air pollution in Wuhan.And we also collected the data of daily cardiovascular and respiratory hospital admissions in a first grade general hospital from 1 January,2013 to 31 December,2015.A semi-parametric generalized additive model was used to evaluate the specific influences of air pollutants on public health.The exposure-response relationship curves between daily hospital admissions and air pollutants were plotted to explore the changed trend between the health effect and air pollutant concentration.The two-pollutant models were estimated to eliminate the effect of col-linearity among the pollutants.In addition,we also examined the influences of different subgroups（sex-,age-and season-groups）,respectively,in order to capture the susceptible sub-populations.Better understanding the influences of ambient air pollution on hospital emergency admissions will provide evidence for developing public health policies and risk assessments of ambient air pollution.This study was consisted of the following two parts.Part 1 The condition of air quality in Wuhan during 2005-2015Objective: To analyze the dynamic changes of air quality in Wuhan during 2005-2015,and to get better knowledge of the characteristics of air pollution in Wuhan.Methods: The data of air pollutants and meteorological data were collected from the data center of the government of People’s Republic of China environmental protection department and the Bureau of meteorology.Spearman correlation method was used to explore the relationships between air pollutants and meteorological factors.Results: In 2005-2012,the rates of fine air quality were 74.25%,74.79%,75.62%,80.6%,82.47%,78.08%,83.84% and 87.7% respectively.In 2013-2015,the rates of fine air quality were 42.19%,46.03% and 51.78%.In 2005-2012,the main primary pollutants in Wuhan were PM10 and SO₂.In 2013-2015,the main primary pollutants in Wuhan were PM2.5,O₃,PM10 and NO₂.The mean of API or AQI reached the maximum in winter,followed by spring and autumn,and reached the minimum in summer.SO₂ and PM2.5 were the most serious in winter;PM10 and PM2.5 were the most slight in summer;O₃ was the most serious in summer,followed by spring and autumn,and was the most slight in winter;NO₂ was the most serious in spring and autumn.The correlation coefficients between API and meteorological factors（air pressure,air temperature,humidity and wind speed）were 0.270,-0.208 and-0.349,respectively.The correlation coefficients between AQI and meteorological factors were 0.334,-0.355 and-0.305,respectively.The correlation coefficients were all statistically significant.Conclusion: The rate of fine air quality was significantly decreased and the air pollution was more serious after using AQI index.After 2013,the main primary pollutants in Wuhan were exchanged from PM10 and SO₂ to PM2.5,O₃,PM10 and NO₂.Air pollution in Wuhan was more serious in winter and more slight in summer.There were weak significant correlation between API/ AQI and meteorological factors.Part2 The effects of air pollution on daily respiratory and cardiovascular diseases hospital admissions in Wuhan from 2013 to 2015Objective: To investigate the associations between ambient air pollution and daily hospital admissions of respiratory and cardiovascular diseases,and to explore the specific differences of sex-,age-,and season-subgroups in Wuhan,China.Methods: The air pollution data（SO₂,NO₂,PM2.5,O₃ and CO）,meteorological data（average air pressure,temperature and humidity）and the data of cardiovascular and respiratory diseases hospital admissions in a first grade general hospital in Wuhan were collected from January 1,2013 to December 31,2015.A semi-parametric generalized additive model was used to evaluate the specific influences of air pollutants on daily respiratory and cardiovascular diseases hospital admissions.At the same time,we examined the modifying effects of sex,age,season on the association.Result: The largest significant effects for SO₂,NO₂,PM2.5,O₃ and CO on respiratory hospital admissions were observed at lag1,lag2,lag03,lag02 and lag0 model,respectively.A 10μg/m3 increment in concentrations of SO₂,NO₂,PM2.5,O₃ were associated with 0.69%（95%CI:-2.47%-3.96%）,0.5%（95%CI:-1.66%-2.7%）,0.87%（95%CI:-0.41%-2.17%）and 0.47%（95%CI:-1.02%-1.97%）increases in respiratory hospital admissions,and a 1mg/m3 increment in concentration of CO was associated with 3.03%（95%CI:-9.37%-17.13%）increases in respiratory hospital admissions.The largest significant effects for SO₂,NO₂,PM2.5,O₃ and CO on cardiovascular hospital admissions were observed at lag02,lag02,lag0,lag03 and lag0 model,respectively.A 10μg/m3 increment in concentrations of SO₂,NO₂,PM2.5,O₃ were associated with 4.02%（95%CI: 0.31%-7.88%）,3.75%（95%CI: 1.26%-6.29%）,0.96%（95%CI: 0.1%-1.83%）and 0.97%（95%CI:-0.34%-2.3%）increases in cardiovascular hospital admissions,and a 1mg/m3 increment in concentration of CO was associated with 13.46%（95%CI: 1.62%-26.68%）increases in cardiovascular hospital admissions.In the subgroups analysis,for respiratory diseases,the 95%CIs of the sex-,age-and season-specific associations were（-0.007-0.006）,（-0.005-0.003）,（-0.001-0.004）,（-0.001-0.005）and（-0.019-0.514）,respectively;the 95%CIs of the age-specific associations were（-0.003-0.01）,（-0.001-0.008）,（-0.003-0.002）,（-0.002-0.004）and（0.003-0.516）,respectively;the 95%CIs of the season-specific associations were（-0.01-0.003）,（-0.004-0.003）,（-0.003-0.001）,（-0.004-0.001）and（-0.323-0.111）respectively.For cardiovascular diseases,the 95%CIs of the sex-specific associations were（-0.008-0.007）,（-0.007-0.003）,（-0.002-0.002）,（-0.005-0.001）and（-0.16-0.29）,respectively;The 95%CIs of the age-specific associations were（-0.004-0.01）,（-0.004-0.006）,（-0.001-0.002）,（-0.003-0.002）and（-0.041-0.395）,respectively;The 95%CIs of the season-specific associations were（-0.007-0.006）,（-0.004-0.004）,（-0.001-0.002）,（-0.002-0.003）and（-0.107-0.262）,respectively.Conclusion: Cardiovascular hospital admissions had positive significant relationships with SO₂,NO₂,PM2.5 and CO,but had an insignificant relationship with O₃.Respiratory hospital admissions had insignificant relationships with SO₂,NO₂,PM2.5,O₃ and CO.Except that the sex-specific difference of association between CO and respiratory hospital admissions was significant（≥65>0-65）,the sex,age,season specific differences of air pollutions to respiratory and cardiovascular hospital admissions were not statistically significant.