基于淋巴细胞计数的多参数模型对间质性肺病急性加重合并肺部感染患者预后的预测价值研究

BackgroundPatients with interstitial lung diseaseILDare prone to acute exacerbationAE-ILDwith infection being a significant trigger. AE-ILD patients exhibit high mortality rates and poor prognosesyet domestic research on this population remains limited. ObjectiveTo investigate the clinical predictive value of dynamic changes in peripheral blood lymphocyte countLYMfor 28-day prognosis in AE-ILD patients with pulmonary infection and to establish a corresponding prognostic prediction model. MethodsA retrospective cohort study included AE-ILD patients hospitalized in the Department of Respiratory Medicine at the Affiliated Hospital of Xuzhou Medical University from January 2022 to June 2024. Patients were stratified into survivaln=37and non-survivaln=65groups based on 28-day outcomes. Data collected included demographicssexagediagnosisILD subtypecomorbiditiesdisease severity scoresAPACHE IISOFAand laboratory parameterswhite blood cell countWBCneutrophil countNEUlymphocyte count on days 13and 5 d1 LYMd3 LYMd5 LYMhemoglobinHbplatelet countPLTprocalcitoninPCTC-reactive protein CRPalbuminALbtotal bilirubinT-billactate dehydrogenaseLDHcreatinineScractivated partial thromboplastin timeAPTTpartial pressure of oxygenPaO2partial pressure of carbon dioxidePaCO2fraction of inspired oxygenFiO2PaO2/FiO2 ratioP/Fand lactateLac. Intergroup differences were analyzedand statistically significant variables were identified. Receiver operating characteristicROCcurves evaluated prognostic predictive capacity. Univariate and multivariate Cox proportional hazards regression analyses were conducted using R software. Scores were assigned to each indicator based on the hazard ratio HR. A nomogram prediction model was constructed. After calculating the total score of each indicator, risk stratification was established. The ROC curve of the prediction model was drawn to evaluate its predictive value. The survival curves of 28-day prognosis of AE-ILD patients with different risk stratifications were plotted using R software, and the 28-day survival rates of patients in different groups were compared. ResultsThe non-survival group exhibited higher than APACHE II scoresSOFA scoresPCTCRPand LDHP<0.05but lower than d3 LYMd5 LYMALband P/FP<0.05. Dynamic LYM trends divergednon-survivors showed progressive lymphopeniawhile survivors demonstrated lymphocyte recovery. The results of the ROC curve showed that the AUCs of d3 LYM , d5 LYM , APACHE II score, and SOFA score in predicting the 28-day prognosis of patients with AE-ILD were 0.723, 0.764, 0.733, and 0.704, respectively. Multivariate Cox regression identified P/FHR=2.0195%CI=1.08-3.75PCTHR=2.1495%CI=1.02-4.49HbHR=2.3495%CI=1.22-4.48d5 LYMHR=2.4095%CI=1.01-5.70as independent predictors of 28-day mortality. The nomogram model was constructed based on d5 LYMP/FPCT and Hb. The AUC value of this model for predicting 28-day mortality in AE-ILD patients was 0.85395%CI=0.781-0.925with the optimal cut-off value being 2. The sensitivity and specificity were 88.24% and 82.35%respectively. According to the results of the optimal risk stratification, 0-2 is classified as the low-risk group, and 3-6 is classified as the high-risk group. There were significant differences on the 28-day survival rates between the two groups of patients2 =51, P<0.001. ConclusionLymphopenia is associated with increased 28-day mortality in AE-ILD patients with pulmonary infection. The nomogram model incorporating LYM-d5P/FPCTand Hb provides a clinically practical tool for risk stratification and prognostic assessment.