The Clinical Characteristics Of Asthma-chronic Obstructive Pulmonary Disease Overlap Syndrome

Background:The coexistence of asthma and chronic obstructive pulmonary disease(COPD) are common,the treatment goal of ACOS is the same as that of asthma and COPD.The treatment mainly depends on long-acting beta-2 receptor agonist(LABA) combined with inhaled corticosteroids(ICS) or long-acting anti-cholinergic drugs(LAMA) combined with ICS But there is no unified diagnostic criteria of ACOS. Therefore, it is necessary to clarify the clinical features of ACOS, which are helpful to early diagnosis and treat the disease.Objective:The aim of this study is to find the differences among ACOS,COPD alone and asthma alone, to evaluate the factors predicting asthma coexisting with COPD among all of these asthma patients,to evaluate the factors predicting COPD coexisting with asthma among all of these COPD patients,to investigate the difference of ACOS with unequal severity stage.Methods:All of these ACOS,asthma alone and COPD alone patients were analyzed restrospectively,who were admitted to the department of respiratory medicine of the our Hospital from January 2014 to June 2014.The general characteristic,past history,auxiliary examination,length of hospital stay of the three groups were compared.According to the forced expiratory volume in one second/predicated value, the ACOS were divided into mild or moderate group, severe group and very severe group.We compared one group with the other two groups respectively.Multi-factor logistic regression analysis was performed to study the risk factors for asthma complicated with COPD and the risk factors for COPD complicated with asthma.The above statistical analysis were accomplished by SPSS 17.0.Results:1.Basic characteristics: The scale of male patients in ACOS group and COPD alone group are separately more than that in asthma alone group(P<0.001,P=0.001). The patients in the ACOS group and COPD alone group are separately older than the patients of asthma alone group(P<0.001,P<0.001), The patients in the COPD alone group are older than that of ACOS group.2.Past History: Compared with the asthma group, less patients had surgery history in ACOS group and COPD alone group( P=0.005,P=0.013).The proportion of patients with history of allergies in COPD group is less than that of asthma group(P=0.008).The proportion of paitient with smoking history in ACOS group and COPD alone group are separately bigger than that of asthma group(P=0.001,P<0.001).3.Auxiliary examination: The proportion of people with increased percentage of neutrophils in ACOS group and in asthma group alone are separately lower than that of COPD alone group(P=0.002,P<0.001).The proportion of people with increased percentage of eosinophilic granulocyte in asthma alone group is higher than that of COPD alone group(P=0.015).ACOS patients and COPD alone patients are separately easier to be with lower albumin( P<0.001,P<0.001) and lower pre albumin(P=0.008,P=0.002) than asthma alone patients.The proportion of people with abnormal creatinine in ACOS is higher than that of asthma alone group(P=0.010).Compared with asthma alone group or COPD alone group, ACOS group is more prone to have abnormal ALT(P=0.016,P=0.016).4.Other aspects:The BMI value of ACOS group and COPD alone group are separately lower than that of asthma(P<0.001,P<0.001)and the BMI value of ACOS group is higher than that of COPD group(P=0.003).The proportion of people with pneumonia in COPD alone group is higher than that of asthma alone group(P<0.001).The value of FEV1%pred(P<0.001,P<0.001)and the value of FEV1/FVC after inhaled bronchial diastolic agent(P<0.001,P<0.001)of ACOS group or COPD group is separately significantly lower than that of asthma alone group.The value of FEV1/FVC after inhaled bronchial diastolic agent of ACOS is significantly lower than that of COPD alone group(P=0.046).The course of disease of ACOS and COPD alone group are separately longer than that of asthma group(P<0.001,P<0.001).The length of hospital stay of in COPD alone group is longer than that of asthma group(P=0.017).5.The smoking index of severe ACOS is less than that of very severe ACOS( P=0.006).The value of FEV1/FVC after inhaled bronchial diastolic agent of mild to moderate ACOS is separately higher than that of severe ACOS and very severe ACOS(P=0.005,P<0.001)),the value of FEV1/FVC after inhaled bronchial diastolic agent of severe ACOS is higher than that of very severe ACOS(P=0.001).Conclusion:1.The more severe the ACOS patient is,the lower the value of FEV1/FVC after inhaled bronchial diastolic agent is.2.The COPD patient with elder age is not prone to coexist with asthma,the COPD patient with higher BMI is more prone to coexist with asthma.3.Male asthma patients are prone to coexist with COPD,asthma patients with lower BMI are more easily combined with COPD, these elder asthma patients are more likely to be associated with COPD, asthma patients with longer duration are easier to coexist with COPD.