Predictive value of serum procalcitonin for acute kidney injury during acute exacerbation of chronic obstructive pulmonary disease

Objective To explore the predictive value of serum procalcitonin(PCT)during acute exacerbation of chronic obstructive pulmonary disease(COPD).Methods According to whether acute kidney injury(AKI)occurred after admission,the patients were divided into two groups of N-AKI and AKI.Apart from dependent variables,clinical data parameters were designated as independent variables.Logistic regression was utilized for estimating the propensity score value and propensity score matching 1:1 nearest neighbor matching adopted.Then the balance of clinical data between two groups after matching was tested and serum level of PCT between two groups at admission was compared by t-test.Pearson’s correlation analysis was utilized for examining the correlation between Ccr and related parameters.Logistic regression model was utilized for evaluating the effect of serum PCT level on AKI.And ROC curve of serum level of PCT was plotted for predicting AKI in patients with acute exacerbation of COPD(P<0.05)and the difference was statistically significant.Results With propensity score matching,a total of 62 pairs of matching were successful in two groups.After matching,clinical data parameters with significant inter-group difference reached balance after matching,and the balance of other parameters without significant difference also significantly improved.After matching,serum PCT levels were significantly different between two groups,serum level of PCT was significantly higher in AKI group than that in N-AKI group(2.4±0.5 vs 0.8±0.3,P<0.05).Pearson’s correlation analysis showed that Ccr was significantly negatively correlated with PaCO₂,D-dimer and PCT.Cox analysis indicated that with an increment of serum PCT by 1 ng/mL,the risk of AKI after acute exacerbation of COPD increased by 158%(HR:1.58;95% CI:1.15-3.62;P=0.038),the sensitivity and specificity of optimal cut-off value of PCT with 1.7 mg/L at admission predicting AKI in patients with acute exacerbation of COPD were 81.6% and 76.5% respectively and the AUROC was 0.778(95%CI:0.712-0.821).Conclusion Serum PCT≥1.7 mg/L at admission is an independent predictor of AKI during acute exacerbation of COPD patients.It may be used as one of the reference parameters for evaluating patient prognosis.