Relationship Between Atopic Dermatitis Outpatient Visits And Air Pollution And The Expression Of CD63 And CD203c In Peripheral Blood Basophils

Part 1Objectives:Studying the relationship between the concentrations of particulate matter(PM_2.5,PM₁₀)and gaseous pollutants（NO₂,SO₂）and the number of patients with atopic dermatitis in Lanzhou.Methods:Based on Poisson distribution generalized additive model and controlling the confounding factors such as seasonality,long-term trend and day of week effect,the outpatient information of patients with atopic dermatitis from January1,2013 to December 31,2019,as well as the data of air pollutants and meteorological conditions in the same period were collected to study the influence of PM_2.5,PM₁₀,NO₂ and SO₂ concentrations on the outpatient visit of atopic dermatitis.Results:In the single pollutant model,PM_2.5 and PM₁₀ had the most obvious effect on the number of patients with atopic dermatitis at lag0,but there was no statistical significance;NO₂ also had the most obvious effect at lag0,and there was a lag effect.The excess risk（ER）and 95%confidence interval（95%CI）of the number of patients with atopic dermatitis were 1.95%（95%CI:1.09%～2.82%）,which were statistically significant.The effect of SO₂ on lag6 was the most obvious.For every 10μg/m³ increase in SO₂ concentration,the number of outpatient visits increased by 1.55%（95%CI:0.48%～2.54%）.The analysis of gender,age and season showed that particulate matter was only sensitive to men.The results showed that PM_2.5 and PM₁₀concentrations increased by 0.91%and 0.22%for each 10μg/m³ increase,respectively.Gaseous pollutants are sensitive to both men and women,and NO₂ is more effective for men than for women.The male increased 1.78%with the increase of NO₂concentration by 10μg/m³,while the female was more sensitive to SO₂.The female increased 2.56%with the increase of SO₂ concentration by 10μg/m³.The influence of gaseous pollutants（NO₂,SO₂）in infants was higher than that in other age groups.For each 10μg/m³ increase in NO₂ and SO₂,the infant group increased by 2.35%and1.57%,respectively,with statistical significance.NO₂ had a significant effect on the population aged 13-59 years old,with an increase of 1.39%for every 10μg/m³ of NO₂.Only NO₂ in the gaseous pollutants had an impact on outpatient visits in cold and warm seasons,with ER values of 2.35%and 1.89%,respectively,with statistical significance.The influence of particulate matter(PM_2.5,PM₁₀)on outpatient visits in winter was significant,but not statistically.In the two pollutant model,PM_2.5,PM₁₀and SO₂were introduced,and NO₂ significantly increased the number of patients with atopic dermatitis compared with the single pollutant model.The interaction between PM_2.5 and NO₂,PM₁₀ and NO₂,SO₂ and NO₂was significant.Conclusion:The air pollutants(PM_2.5,PM₁₀,NO₂,SO₂)in Lanzhou City were closely related to the number of outpatients with atopic dermatitis,and the increased concentration of NO₂ and SO₂ was more likely to increase the risk of atopic dermatitis.Part 2Objectives:The number and activation degree of basophils of peripheral in AD patients and healthy volunteers were detected by flow cytometry.The relationship between the number and activation degree of basophils in the two groups was analyzed,and the correlation between the change of basophils activation degree in peripheral blood of AD patients and the severity of the disease was analyzed.Methods:From April 2020 to September 2020,30 patients with AD were selected from the Department of Dermatology of the first hospital of Lanzhou University,and 30 healthy people with matched gender,age and case group were selected from the physical examination center of our hospital during the same period.Flow cytometry was used to detect the number and activation level of basophils in peripheral blood of AD group and healthy control group.Then,the correlation between basophil activation and EASI score,total Ig E,serum complement C₃,C₄ and immunoglobulin（Ig G,Ig A,Ig M）was analyzed.Results:the serum total Ig E level,peripheral basophil count and basophil percentage of AD patients were higher than those of healthy control group（P<0.05）,and the basophil CD63⁺,CD203c⁺and CD63⁺CD203c⁺activation percentage were also higher than those of control group（P<0.05）.Basophil activation in peripheral blood of AD patients was positively correlated with EASI score（r=0.907,P=0.000）,serum complement C₃（r=0.448,P=0.013）,C₄（r=0.701,P=0.000）,total Ig E（r=0.223,P=0.235）,Ig G（r=0.381,P=0.037）,but not Ig A and Ig M（P>0.05）.Conclusion:Compared with the normal control group,the number and activation of basophils in peripheral blood of AD patients are increased,which is related to the severity of AD.