Association Of Gaseous Air Pollutants And Daily Outpatient Visits For Urticaria In Lanzhou

Objective To determine the relationship between gaseous air pollutants and outpatient visit for urticaria,and the sensitivity of different seasons,gender,and age groups to gaseous air pollutants in Lanzhou,China.Methods Data of daily urticaria outpatient visits,concentrations of gaseous pollutants?SO₂,NO₂,O₃8h?and meteorological variables during the period from 2013.1.18 to 2017.12.31 were collected.A distributed lag nonlinear model?DLNM?was used to analyze the exposure-effect relationship between gaseous pollutants?SO₂,NO₂,O₃8h?and Daily Outpatient Visits for urticaria,based on the control of long-term trends and“day of-week”effects,At the same time,the model was established based on the different groups.Results 1.In the single pollution model,every increase of 10?g/m³of NO₂ and SO₂ concentration had the most significant lag effect on the outpatient visits of urticaria in lag0d and lag07,effect values were 4.60%,3.15%,6.25%and 3.35%,respectively.each increase of 10?g/m³ of O₃8h concentration had the most significant effect on the daily outpatient visits of the whole population in Lag2d and lag06,the daily outpatient visits decreased by 0.50%and 0.75%,respectively.2.In the single pollution model,after the gender stratification analysis,NO₂ and SO₂ concentration increase 10?g/m³ outpatient visits for male outpatients with urticaria slightly higher than women,the effect in lag0d,lag0d,lag07d and lag01d,male outpatients with urticaria,outpatient visits respectively increased by 4.74%,3.92%and 5.93%,3.57%.the concentration of O₃8h increased by 10?g/m³,the number of male urticaria outpatients decreased by 0.92%and 1.29%in lag2d and lag06d,respectively,but the effect on the number of female urticaria outpatients was not statistically significant.3.In the single pollution model,after stratifying depending on age,NO₂ and SO₂concentration increase 10?g/m³,the impact on the 0¹8 years old adolescent outpatients with urticaria,compared with other two groups of age groups of outpatients with urticaria effect significantly,in lag0d,lag0d,lag07d and lag02d reaches the effect value,respectively.effect values were 5.55%,5.58%,7.50%,5.78%,respectively.For every 10?g/m³ increase in O₃8h concentration,the effect on elderly urticaria outpatients aged?65 years was the most obvious,and the daily outpatient visits at lag2d and lag04d were reduced to 1.17%and 1.71%,respectively.4.In the single pollution model,After the division of cold and warm seasons,every increase of NO₂ and SO₂ concentration of 10?g/m³ on the daily outpatient visits of urticaria population in cold season was significantly higher than that in warm season,and the influence was 5.15%and 2.87%respectively in lag0d.The effect of every increase of O₃8h concentration of 10?g/m³ in different seasons on the daily outpatient visits of urticaria showed a two-way effect,the effect of every increase of O₃8h concentration of 10?g/m³ in warm season was positive correlation with the daily outpatient visits of the whole population of urticaria while the effect show the negative correlation in cold season,the effect value were 0.63%and-1.04%.5.Results of the study on the relationship between exposure and response:the change of SO₂ and NO₂ concentration had a linear relationship with the daily outpatient visits of urticaria,while the exposure and response graph of O₃8h concentration and the daily outpatient visits of urticaria presented a u-shaped segmented linear trend.6.SO₂ and O₃8h were included in the double-pollution model,the correlation between NO₂ and daily outpatient visits for urticaria increased and decreased,respectively.After adjusting the concentrations of SO₂ and NO₂,the correlation between O₃8h and urticaria outpatient visits was weakened.Conclusions 1.The number of daily outpatient service for urticaria was p ositively correlated with the changes of SO₂ and NO₂ concentration in the air,and the positive correlation between NO₂ and daily outpatient for urticaria was more significant than that of SO₂.The change of SO₂ and NO₂ concentration had a linear relationship with the daily outpatient visits of urticaria.2.The sensitivity of daily urticaria outpatient visits to air pollutants varies among different gender and age groups,with male and aged 0¹8 urticaria outpatients being the most sensitive to changes in SO₂ and NO₂ concentrations.3.After stratification in cold and warm seasons,the correlation effect between O₃8h and urticaria showed a two-way effect,which may be related to different concentration levels,that is,a negative correlation at a certain concentration and a positive correlation at another concentration level.the exposure and response graph of O₃8h concentration and the daily outpatient visits of urticaria presented a u-shaped segmented linear trend.4.Three gaseous pollutants?SO₂,NO₂ and O₃8h?,have interactive effects on the daily outpatient visits of urticaria.