Application Value Of HBP And SAA In COPD Patients With CAP

Objective（s）:To investigate the correlation between heparin-binding protein（HBP）,serum amyloid A（SAA）and chronic obstructive pulmonary disease（COPD）with community-acquired pneumonia（CAP）,acute exacerbation of chronic obstructive pulmonary disease（AECOPD）,and to evaluate their role and clinical application value in the early diagnosis and disease evaluation of COPD with CAP.Methods:154 COPD patients hospitalized for worsening respiratory symptoms in the Department of Respiratory and Critical Care Medicine of the First People’s Hospital of Kunming from December 2021 to January 2023 were selected as the experimental group and divided into AECOPD group（n=30）and COPD with CAP group（n=124）according to imaging changes（chest CT）.COPD+CAP group patients were divided into low,medium and high risk groups according to the Pneumonia Severity Index（PSI）score;40 COPD patients in the stable COPD（SCOPD）who visited the outpatient department at the same time were selected as the control group.Collect the baseline data,vital signs,blood routine,routine biochemical indicators,blood gas analysis,pulmonary function,C-reactive protein（CRP）,procalcitonin（PCT）,interleukin-6（IL-6）,white blood cell（WBC）and other indicators of the subjects in each group,determine the HBP and SAA levels by immunofluorescence dry quantification and immunoturbidimetry,respectively,and compare the HBP and SAA differences among the three groups of SCOPD,AECOPD and COPD+CAP;then analyze the differences between HBP and SAA in different risk groups of COPD+CAP by pairwise comparison between groups,study the correlation between HBP,SAA and risk stratification of PSI death by Spearman correlation analysis,explore the correlation between HBP and SAA levels and the percentage of predicted forced expiratory volume in 1 second（FEV₁%pred）and forced expiratory volume in the first second（FEV₁/FVC）of pulmonary function in COPD+CAP group,and draw ROC curve to evaluate whether HBP and SAA have higher value in the early diagnosis of COPD with CAP.Results:1、The levels of HBP,SAA,CRP,PCT,IL-6 and WBC in patients with SCOPD,AECOPD and COPD+CAP were compared.The results showed that the levels of HBP,SAA,CRP,PCT and IL-6 in patients with SCOPD,AECOPD and COPD+CAP were statistically different（P<0.05）,and the levels of each index were COPD+CAP group>AECOPD group>SCOPD group;the WBC levels were not significantly different among the three groups（P>0.05）;the levels of HBP,SAA,CRP and IL-6 in patients with SCOPD,AECOPD-AECOPD+CAP and SCOPD-COPD+CAP were compared between the two groups（P<0.05）;the PCT levels in patients with AECOPD-COPD+CAP were not significantly different（P>0.05）,and there was no significant difference between patients with SCOPD-AECOPD and SCOPD-COPD+CAP（P<0.05）.2、the patients in the COPD+CAP group were stratified for the risk of death according to the PSI score,and the results showed that there were differences in the levels of HBP,SAA,CRP,PCT,and IL-6 between the groups（P<0.05）,and the levels of the above indicators also increased with the increase of the risk of death in the COPD+CAP group;however,the WBC levels were not significantly different between the groups（P>0.05）;the HBP,SAA,and CRP levels were significantly different between the low,medium,and high groups（P<0.05）;the PCT and IL-6levels were not significantly different between the medium and high groups（P>0.05）,and there were significant differences between the low–medium groups and the low–high groups（P<0.05）;WBC was not significantly different between the low,medium,and high groups（P>0.05）;The results showed that the levels of HBP,SAA,CRP,PCT and IL-6 were positively correlated with the risk stratification of death（r>0,P<0.05）,while WBC was not correlated with the risk stratification of death（P>0.05）.3、The correlation between HBP and SAA levels and FEV₁%pred and FEV₁/FVC in COPD+CAP group was analyzed.The results showed that HBP and SAA were negatively correlated with FEV₁%pred and FEV₁/FVC（r<0,P<0.05）.4、ROC curve analysis showed that the AUC of HBP,SAA,CRP,PCT,IL-6 and WBC were 0.943,0.933,0.899,0.804,0.833 and 0.527,respectively,and the AUC of HBP was the largest.When HBP was set at a cutoff value of 15.61 ng/ml,the sensitivity and specificity were 91.7%and 95.3%,respectively,all of which were the highest,and the diagnostic value was the largest;when SAA was set at a cutoff value of 7.81 mg/L,the sensitivity and specificity were 89.2%and 90.5%,respectively,and the diagnostic value was high;when HBP and SAA were combined,the AUC was0.956,and the combined diagnostic value was high.Conclusion（s）:1、Compared with AECOPD and COPD patients,HBP and SAA increased more significantly in COPD patients with CAP,and HBP and SAA can be used for the auxiliary diagnosis of COPD patients with CAP.2、HBP and SAA were positively correlated with the severity of illness and pulmonary function injury in COPD patients with CAP,and HBP and SAA were of certain value in assessing the severity of illness and pulmonary function in COPD patients with CAP.3、Compared with CRP,PCT,IL-6 and other traditional infection markers,HBP has the highest diagnostic value for COPD with CAP,followed by SAA,and the diagnostic value is better than a single index when the two indicators are tested in combination.