Expression And Clinical Significance Of GDF-15 In Serum Of Patients With Frequent Exacerbation Of COPD

Objective:To detect the expression level of GDF-15 in peripheral blood of patients with COPD,and to explore the correlation and clinical significance between the change of GDF-15 expression level and the frequency of COPD acute exacerbation,and the predictive value of GDF-15 expression level on different outcomes in patients with frequent exacerbation.Methods:(1)Seventy-two patients who were diagnosed as COPD in the Second Department of Respiratory Medicine of the First Hospital of Bethune,Jilin University from September 2020 to January 2021 were selected.According to the frequency of acute exacerbations within 1 year before admission,CIVOPD patients were divided into group A(infrequent plus recombination,≤2 times/year)and group B(frequent plus recombination,>2 times/year).Meanwhile,30 healthy subjects who underwent physical examination in Physical Examination Center of Jilin University from September 2020 to January 2021 were selected as the healthy control group.(2)The general demographic characteristics of the selected patients were collected.Common clinical indicators for patients with COPD were enrolled.The percentage of forced respiration volume in the first second(FEV1%pred)of lung function parameters was measured by pulmonary function meter.The concentration of GDF-15 in peripheral blood of all subjects was determined by enzyme linked immunosorbent assay(ELISA).(3)SPSS22.0 was used for data analysis.The general data characteristics of each group were compared between groups;The expression level of GDF-15 in peripheral blood of each group was analyzed by rank sum test.Spearman correlation coefficient was used to analyze the correlation between GDF-15 expression level and frequency of acute exacerbation.Receiver operating characteristic(ROC)curve and area under curve(AUC)were used to analyze the specificity and sensitivity of GDF-15 in evaluating the frequency of acute exacerbation and the different outcomes in patients with frequent recombination.Results:(1)There was no significant difference in age,gender,smoking history,drinking history and other general information between infrequent and frequent recombination and control group(p>0.05).(2)There were statistically significant differences in FEV1/pred(%),Pa O2,Pa C02,Sa O2,FIB and frequency of acute exacerbation between infrequent and frequ~Vent recombination patients(p<0.05),while there were no statistically significant differences in time of disease,CRP,PCT,LAC,D-Dimer and BNP(p>0.05).(3)The expression level of GDF-15 in peripheral blood increased in healthy control group,infrequent recombination and frequent recombination(Frequent addition of recombination group>Not frequent addition of recombination group>controls group),and there were significant differences among all groups(p<0.001).The expression level of GDF-15 was positively correlated with the frequency of acute exacerbation(r=0.645,p<0.001).The area under the ROC curve for GDF-15 evaluation of frequent aggravation was 0.856.(4)A total of 11 patients in the COPD group had poor outcomes and received non-invasive ventilator assisted ventilation or nasal high-flow oxygen inhalation.8(25%)patients with frequent recombination and 3(7.5%)patients with infrequent recombination were added,and there was a difference between the groups(p<0.05).Frequent addition and recombination were divided into poor prognosis group and no adverse prognosis group.The expression level of GDF-15 in the poor prognosis group was higher than that in the no adverse prognosis group(p=0.001).There were significant differences in FIB,BNP,Lac,Pa O2 and FEV1/pred(%)between the two groups(p<0.05).The area under the ROC curve of GDF-15 for evaluating poor prognosis in group B was0.896.Conclusion:(1)The levels of PaO2,SaO2 and FEV1/pred(%)in COPD patients with frequent addition of recombination were lower than those in patients with infrequent exacerbation,while the levels of Pa CO2 and FIB were higher than those in patients with infrequent exacerbation.(2)The expre~Vs~Ision level of GDF-15 increased in both infrequent and frequent recombination,but the expression level was higher in serum of frequent recombination patients,and there was a positive correlation between the expression level of GDF-15 and the frequency of acute exacerbation.(3)Patients with frequent plus recombination had a higher proportion of poor prognosis than patients with infrequent plus recombination,and patients with poor prognosis showed higher expression levels of GDF-15.