Clinical Significance Of Serum Albumin To Globulin Ratio In Patients With Acute Exacerbation Of Chronic Obstructive Pulmonary Disease

Background and ObjectiveAcute exacerbation of chronic obstructive pulmonary disease(AECOPD)is one of the common and multiple respiratory diseases and has become one of the major public health problems in the world.Albumin to globulin ratio(AGR)is combines the two indexes of albumin and globulin,which can reflect the nutritional status and inflammation condition of patients.At present,it is applied in tumor,heart failure,Non-ST-elevation myocardial infarction,myasthenia gravis and other diseases in domestic and foreign studies as an indicator of good prognosis for patients.Although there are currently studies using albumin and globulin in patients with AECOPD respectively,there are fewer studies using AGR in AECOPD;the purpose of this study was to investigate the clinical significance of the ratio of serum albumin to globulin in patients with acute exacerbation of chronic obstructive pulmonary disease:including the predictive value of prognosis,severity and assessment of lung function.Materials and MethodsRetrospective analysis was used to collect clinical data of 126 patients admitted to the Department of Respiratory and Critical Care Medicine,Second Affiliated Hospital of Zhengzhou University from January 2016 to May 2018 with the first diagnosis of AECOPD,94 males and females 32 cases,with an average age of(73.68± 8.34)years old.The general information of the patients included gender,age,height,weight,body mass index(BMI),smoking history,drinking history,length of hospital stay and comorbidities,pulmonary function indicators:forced expiratory volume in the first second(FEV1),forced vital capacity(FVC),forced expiratory volume in the first second as percentage of predicted volume(FEV1%pred),ratio of forced expiratory volume in the first second to forced vital capacity(FEV1/FVC),admission 24h Laboratory indicators:including serum total protein(TP),albumin(ALB),interleukin-6(IL-6),C-reactive protein(CRP),procalcitonin(PCT);globulin(GLB)calculated from total protein and albumin,GLB=TP-ALB,AGR＝ALB/(TP-ALB),chest CT results and sputum culture results.Follow-up performed by telephone and consulting medical records,the endpoint event of this study was re-admission or death due to AECOPD within one year.May 2019 and the number of re-admission,the number of re-admission times and the number of deaths due to AECOPD within one year after discharge were counted.The study subjects were grouped according to different prognosis:① Poor prognosis group:that was to be re-admitted to hospital for treatment or death due to acute exacerbation within one year of discharge;② Good prognosis group:that was,no re-admission for treatment due to acute exacerbation within one year of discharge,60 poor prognosis group,66 cases with good prognosis and 11 deaths.The general information,biochemical indexes and inflammation indexes were compared between the two groups.According to the ROC curve,considering the sensitivity and specificity,the optimal cutoff value of AGR for predicting the prognosis outcomes of AECOPD patients was 1.295.Therefore,with the optimal cutoff value as the critical value the study subjects were divide into high AGR group(AGR≥1.295)and low AGR group(AGR<1.295),the general information,lung function,inflammation indexes,and prognosis indexes were compared between the two groups.Pearson or Spearman correlation analysis was used to analyze the correlation between AGR and BMI,CRP,IL-6,PCT,FEVi%pred,length of hospital stay and prognosis.Results1.The study subjects were grouped according to the different prognosis:66 cases with good prognosis,20 females,46 males,with an average of age(72.32±8.61)years old,and 60 cases with poor prognosis,12 females,48 males,with an average age(75.18±7.85)years old.There was no statistical difference in gender,age,BMI,smoking history,and drinking history between the two groups(P>0.05).The length of hospital stay in the group with good prognosis was shorter than that in the group with poor prognosis,and there was a statistically significant difference(P<0.05).The albumin and AGR levels in the good group were higher than those in the poor prognosis group,and the globulin levels were lower than those in the poor prognosis group.There were statistically significant difference(P<0.05).The total protein levels in the good prognosis group were higher than those in the poor prognosis group,but the differences were not significant.And there was no statistical significance(P>0.05);the levels of CRP,IL-6 and PCT in the group with good prognosis were lower than those in the group with poor prognosis,and there were statistically significant differences(P<0.05).2.According to the results of ROC curve analysis,the study subjects were divided into high AGR group(AGR>1.295)and low AGR group(AGR<1.295):76 the high AGR group,57 males and 19 females,with an average age of(72.80 ± 8.26)years old,and 50 cases in the low AGR group,37 cases in males and 13 cases in females.The average age was(75.02 ± 8.38)years old.There were no statistical differences in age,gender,smoking history and drinking history between the two groups(P>0.05).The levels of BMI,FEVi%pred,FVC(%pred)and FEV1/FVC%in the high AGR group were higher than those in the low AGR group,and there were statistically significant differences(P<0.05).The CRP,IL-6,PCT levels,and chest CT lung inflammation positive rates in the high AGR group were lower than those in the low AGR group,and there were a statistically significant differences(P<0.05).The positive rate of sputum culture was lower than that in the low AGR group,but the difference was not significant and statistically significant(P>0.05).In the high AGR group,patients who were re-admitted due to acute exacerbation within one year 19 cases(25%),including 2 deaths(2.6%),and 41 patients(82%)in the low AGR group,of which 9(18%)died,and there was a statistically significant difference(P<0.05).The hospital stay of patients in the high AGR group was shorter than that in the low AGR group,and there was a statistically significant difference(P<0.05).3.Correlation analysis between AGR and BMI,CRP,PCT,IL-6,FEV 1%perd,length of hospital stay and prognosis in patients with AECOPD:AGR was linearly negatively correlated with CRP(r=-0.431,P=0.000),and PCT was linearly negative correlation(r=-0.412,P=0.000),IL-6 showed a linear negative correlation(r=-0.542,P=0.000),hospital stay time showed a linear negative correlation(r=-0.508,P=0.000),and the prognosis was linear negative correlation(r=-0.501,P=0.000),and linear positive correlation with BMI(r=0.196,P=0.028),FEV1%pred was linear positive correlation(r=0.215,P=0.016).Conclusion1.AGR took into account both ALB and GLB levels,was not affected by blood concentration and dilution,and could simultaneously reflect the body’s nutritional status and inflammatory response.2.AGR was negatively correlated with some indicators related to inflammatory response.3.AGR could be used as an index to evaluate the severity of pulmonary function in patients with AECOPD.4.AGR could be used as an index to predict the prognosis of patients with AECOPD.