Spatial Correlation Study On Prevalence Rate Of Asthma And Environmental Factors In Jinan

As an incurable chronic respiratory disease,asthma seriously endangers human health,increases the economic burden of the people,and affects the daily life of the masses.In recent years,the rapid rise in the prevalence of asthma has,to a great extent,a potential link with the shift in environmental factors.Identifying the spatial correlation between environmental factors and the prevalence of asthma can help to further promote the pathological mechanism of asthma and provides an objective basis for effective prevention and controls of asthma,the development of related health policies and rational allocation of medical resources..This disquisition was developed on support the National Natural Science Foundation of China（41371395）,Geological Environmental Monitoring Station Project in Shandong Province（Lu Kan Word【2011】14）.The dissertation sets the five urban areas of Ji’nan（Shizhong District,Lixia District,Tianqiao District,Huaiyin District,and Licheng District）as the research area.Based on the data of the 2009asthma patient and 15 environmental factors,which is remote sensing,monitoring,statistics,and interpolation data.Describe spatial distribution characteristics of the prevalence of asthma and the environmental factors,quantitatively analyze the correlation between the two,define the correlation coefficient between various environmental factors and the prevalence of asthma,simulate and predict the risk of asthma and the classification of asthma.By means of mathematical statistics,the geographical detectors,spatial autoregressive model,geographical weighted regression modeling and decision tree model.To explore the spatial correlation between the disease rate of asthma and the environmental factors.The research results are finally summarized as the following conclusions:（1）The number of female asthmatic patients in the study area is higher than that of males,mostly in the age group of 51-70 years old.The prevalence rate of asthma in the Lixia district is the highest and that in Tianqiao district is the lowest.The prevalence of asthma in the neighboring street has spatial similarity,and exist high-high,low-low,low-high accumulation areas.The hot spot gathering area is flat oval.It is located at the junction of Tianqiao District,Lixia District,Huaiyin District,and Shizhong District.The overall prevalence of asthma in the study area presents a spatial pattern that centered on the the center of gravity,a little bit towards the west,decreasing outwardly concentrically circular.The highest incidence cases of asthma was the in September and the lowest in February;it was the highest in autumn（September-November）and the lowest in winter（February-February）;The age range from 51 to 70 has a high risk of asthma.（2）The average annual concentration of CO,NO₂,and SO₂ is lower in the northwest and higher in the southeast.O₃ happens to be the opposite.The average annual concentration of PM₁₀0 in the north is higher than that in the south.The annual average relative humidity in the study area is increasing gradually from the southwest to the center,and the average annual temperature is opposite.The average annual wind speed gradually decreases from southwest to north.The average annual precipitation in the study area decreases from the southwest to the northeast,and the average annual pressure in the north is higher than that in the south.In the research areas,the terrain is higher in the southeast and lower in the northwest,and the vegetation coverage is concentrically increasing gradually from the the center of gravity,a little bit towards the northwest to outward.Major waste gas monitoring companies are located in the northern part of the study area,generally distributed along the southwest-northeast line.The road network density has the distribution characteristic that the northwest is greater than the southeast.The per capita GDP generally shows a characteristic that the southeast and northern borders are lower,and higher in the the center of gravity,a little bit towards east and west.The overlay of environmental factor interpolation maps and patient distribution points reveals that there is a certain correlation between the two.（3）With regard to the degree of spatial correlation between environmental factors and the prevalence of asthma,the annual average concentration of SO₂ has strongly correlation with the prevalence of asthma,and there is a significant impact on the spatial distribution of asthma prevalence.The annual average precipitation has less correlation and has no significant effect.And the influence of the combination of any two environmental factors on the spatial distribution of asthma prevalence will increase.In terms of the direction of environmental factors,NDVI,elevation,average annual air pressure,distance from patient address to key exhaust gas monitoring companies,and patient-to-road distance were negatively correlated with the prevalence of asthma.Other factors were positively correlated.According to the spatial distribution characteristics of various factors,the correlation of PM₁₀0 average annual concentration gradually increases from the southwest to the northeast,the average annual temperature and elevation are exactly opposite.The annual average concentration of SO₂ is centered on the northwestern part and descends semi-circularly eastwards and northwards.The average annual pressure correlation decays gradually from northwest to southeast.Per Capita GDP is gradually decreasing from west to east.The patient-to-road distance coefficient shows a bidirectional change from southwest to northeast and from east to west.（4）Model predictions show that the area of high prevalence of asthma is still concentrated in the central and western regions,take it as the heart with the center of the ring decreasing towards the periphery.Shizhong District and Licheng District occupy the largest area in the high-low value areas of asthma prevalence.The highest risk of asthma prevalence is in Erqi Street.Based on equal intervals,the prevalence of asthma was divided into five risk categories,and the number of streets belonging to the heavy risk area was the highest.NDVI is the most critical factor in predicting the prevalence of street asthma.The distance from the patient’s address to the key exhaust gas monitoring company and the average annual temperature are important to predict the risk of asthma.