| BackgroundChronic obstructive pulmonary disease（COPD）is a kind of common respiratory disease characterized by irreversible persistent respiratory symptoms and airflow limitation caused by airway and/or alveolar abnormalities.In recent years,the global prevalence of COPD has maintained a high level and continues to rise,and it brings serious disease burden and economic burden to the society and individuals.Studies have found that the prevalence of COPD varies in different regions,which may be related to the environmental factor,economic level,urbanization,population aging and other factors.Gansu Province is located in the western region of China,with lower economic level than other provinces.The prevalence of COPD among rural residents in Gansu Province has not been studied systematically.Therefore,the purpose of study is to explore the basic status and influencing factors of COPD in rural areas of Gansu Province based on the surveillance project of COPD among rural residents in Gansu Province.ObjectiveTo explore the prevalence and risk factors of COPD among residents aged 40 and above in rural areas of Gansu province,so as to provide the scientific basis for Gansu government to formulate policies for the prevention and treatment of COPD.MethodsThis study was based on the Gansu data of the COPD surveillance project for Chinese residents from 2014 to 2015.The sampling survey was conducted by multi-stage cluster random sampling,and the subjects were all local residents aged 40 and above who lived for a long time in rural areas of Dunhuang City,Cheng County and Zhengning County.A total of 1800 subjects were investigated with questionnaire,physical examination and lung function test.The questionnaire included basic demographic information,knowledge of disease,personal and family history,respiratory symptoms,risk factors of COPD,contraindications of lung function examination and so on.Physical examination included height,weight and other indicators,and lung function tests included basic tests and lung function tests after the administration of bronchodilators（salbutamol）.According to GOLD（2017）,COPD was defined as FEV1/FVC less than 0.70 after taking a bronchodilator（salbutamol）,confirming persistent airflow limitation.The general characteristics of the research object were described in two formats,in which quantitative data with normal distribution were expressed as average and standard deviation（（?）±S）,and qualitative data were expressed as frequency and percentage[n（%）].We calculated the prevalence rate of COPD and the severity of airflow limitation in the study population.The difference of COPD prevalence in different characteristics and the relationship between COPD and respiratory symptoms were analyzed by X~2 test.The rank sum test（Mann-Whitney U or Kruskal-Wallis H test）was used to compare the differences in the severity of different patients.Univariate logistic regression and multivariate logistic（forward LR method）were used to analyze the risk factors of COPD,and explored influencing factors of COPD prevalence in different regions and different genders.Results（1）Through collation of data,a total of 1,583 people were qualified and included in the study analysis,including 901 males and 682 females.The average age of the population was（54.1±9.1）years old,and the education level was mainly primary school and below（52.2%）and junior high school to senior high school level（45.2%）.In Gansu rural areas,the awareness rate of COPD name was 5.7%,6.5%for men and 4.7%for women.The knowledge of COPD in these participants were mainly learned from multimedia（television,radio and networks）and hospitals.（2）The prevalence of COPD in the surveyed areas of Gansu was 18.8%.Mild,moderate and severe COPD patients accounted for 78.8%,18.8%and 2.4%,respectively.The severity of airflow limitation in women is higher than in men（P<0.05）.The prevalence rate of COPD was24.2%in males and 11.6%in females,and there were significant differences between different genders（P<0.05）.The prevalence of COPD in different age groups was different and increased with age（P<0.05）.The prevalence rate in Dunhuang City was higher than the other two places,and there were significant differences in the prevalence rate of COPD among Dunhuang City,Cheng and Zhengning County（P<0.05）.The smokers showed significantly higher rate of COPD than non-smokers,and people with primary diseases like respiratory disease and diabetes also had higher COPD prevalence than other people（P<0.05）.There were significant differences in the prevalence of COPD among residents who cooked with different fuels,among which the prevalence of cooking with coal was the highest（P<0.05）.There were 14.5%,12.8%,14.5%and32.3%COPD patients who had symptoms of cough,persistent cough,persistent expectoration and dyspnea,respectively,and the incidence of these respiratory symptoms in COPD patients was higher than that in non-COPD people（P<0.05）.（3）The results of multivariate logistic regression showed that the risk factors of COPD in the surveyed areas of Gansu included older age（40～49 years old as the control group;50～59 years,OR=1.710,95%CI:1.212～2.412;60～69 years,OR=3.164,95%CI:2.226～4.497;70 years and above,OR=4.122,95%CI:2.439～6.968）,male（female as control group,male OR=1.874,95%CI:1.320～2.662）,respiratory disease history（no respiratory disease history as the control group,respiratory disease history OR=1.641,95%CI:1.184～2.275）,smoking（non-smoker as the control group,smoker OR=1.532,95%CI:1.104～2.126）,coal cooking（clean fuel cooking as the control group,coal cooking OR=1.732,95%CI:1.149～2.610）and living in the Hexi area（eastern area as the control group,Hexi area OR=2.435,95%CI:1.617～3.667）.（4）The influencing factors of COPD in Cheng county included gender（male OR=2.219,95%CI:1.137～4.330）,age（50～59 years old,OR=1.993,95%CI:1.033～3.845;60～69 years old,OR=4.234,95%CI:2.230～8.039;among 70 years old,OR=5.267,95%CI:2.225～12.466）,history of respiratory diseases（OR=2.720,95%CI:1.420～5.209）and smoking（OR=1.915,95%CI:1.094～3.351）.The influencing factors of COPD in Dunhuang were gender（male OR=2.692,95%CI:1.682～4.308）and age（50～59 years old OR=2.145,95%CI:1.227～3.749;60～69 years old,OR=3.793,95%CI:2.115～6.801;above 70 years old,OR=25.748,95%CI:5.015～132.195）.Smoking（OR=2.160,95%CI:1.342～3.474）was the influencing factor of COPD in Zhengning county.The influencing factors of female COPD were cooking fuels（coal cooking OR=2.555,95%CI:1.339～4.875）,while the influencing factors of male COPD included history of respiratory disease（OR=1.637,95%CI:1.093～2.452）,smoking（OR=1.643,95%CI:1.168～2.311）and age（50～59 years old,OR=1.902,95%CI:1.234～2.932;60～69years old,OR=3.692,95%CI:2.407～5.663;over 70 years old,OR=5.136,95%CI:2.791～9.451）,diabetes history（OR=2.899,95%CI:1.103～7.619）and living in different areas（Dunhuang OR=2.640,95%CI:1.726～4.039;Cheng county OR=1.514,95%CI:1.014～2.260）.Conclusions（1）The prevalence of COPD among people aged 40 and above in the surveyed area was18.8%,which was relatively higher compared with other regions of China.Therefore,it is of great significance to prevent the further development of COPD.（2）The awareness rate of COPD in the study population is considerably low,only around5.7%,so it is quite necessary to strengthen health education for rural population,improve health literacy,and enhance the awareness of disease prevention.（3）Older age,male,history of respiratory diseases,smoking,cooking with coal,and people living in Hexi area of Gansu are at higher risk of COPD than other groups,suggesting that the prevention and control of COPD should pay more attention to the population with these characteristics. |
