社区获得性肺炎患者外周炎症比值与凝血功能的关系研究

Study on the Relationship between Peripheral Inflammation Ratio and Coagulation Function in Patients with Community-Acquired Pneumonia

摘要: 目的：探讨社区获得性肺炎(community-acquired pneumonia, CAP)患者外周血炎症指标比值与凝血功能参数的变化特征，分析其相互关系，并评估炎症比值在传统指标基础上的增量诊断价值。方法：选取确诊为CAP的住院患者及同期健康体检者，采用回顾性病例–对照研究方式，对外周血中中性粒细胞/淋巴细胞比值(neutrophil-to-lymphocyte ratio, NLR)、血小板/淋巴细胞比值(platelet-to-lymphocyte ratio, PLR)、系统免疫炎症指数(systemic immune-inflammation index, SII)以及C反应蛋白(C-reactive protein, CRP)及凝血参数进行比较分析。组间差异采用Mann-Whitney U检验，在CAP组内通过Spearman相关分析，并分别构建不同炎症比值的多因素Logistic回归模型，结合ROC曲线、AIC/BIC及重分类指标评价模型判别效能。结果：CAP患者多项炎症指标及凝血相关参数水平高于健康对照(均P < 0.05)。NLR、PLR和SII与FIB、D-二聚体水平呈正相关(均P < 0.01)。多因素Logistic回归分析提示，CRP和FIB是区分CAP与健康对照的相对稳定的独立相关因素(均P < 0.05)。模型比较显示，不同炎症比值模型的AIC/BIC差异较小。重分类分析结果显示，引入NLR和PLR后模型的总体重分类能力显著改善(NRI均P < 0.01)，而SII未显示增量判别价值；各模型的IDI均未达统计学显著性(P > 0.05)。结论：CAP患者普遍存在炎症反应增强并伴随凝血功能改变，部分炎症比值指标(NLR、PLR)在传统炎症及凝血指标基础上具有一定补充价值，而SII的增量诊断意义有限。联合评估炎症与凝血相关指标，有助于更全面地反映CAP的实验室特征。

Abstract: Objective: To investigate alterations in peripheral inflammatory ratio indices and coagulation parameters in patients with community-acquired pneumonia (CAP), and to assess the incremental diagnostic value of inflammatory ratios beyond conventional laboratory markers. Methods: This retrospective case-control study included hospitalized patients with CAP and healthy individuals undergoing routine physical examinations. The neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), C-reactive protein (CRP), and coagulation parameters were compared between groups. Group differences were assessed using the Mann-Whitney U test. Associations between inflammatory and coagulation indices were evaluated using Spearman correlation analysis. Separate multivariable logistic regression models incorporating different inflammatory ratios were constructed, and model performance was assessed using receiver operating characteristic (ROC) curves, Akaike and Bayesian information criteria (AIC/BIC), and reclassification indices. Results: Patients with CAP exhibited significantly higher levels of inflammatory and coagulation-related parameters than healthy controls (all P < 0.05). NLR, PLR, and SII were positively correlated with fibrinogen and D-dimer levels (all P < 0.01). Multivariable analysis identified CRP and fibrinogen as stable independent factors associated with CAP (all P < 0.05). Model comparison showed minimal differences in AIC and BIC. Reclassification analysis demonstrated that adding NLR or PLR significantly improved overall risk reclassification (NRI P < 0.01), whereas SII provided no incremental benefit. No model showed significant improvement in integrated discrimination improvement (P > 0.05). Conclusion: CAP is characterized by enhanced inflammation accompanied by coagulation abnormalities. NLR and PLR offer limited supplementary diagnostic value beyond traditional markers, whereas SII shows little incremental utility. Jointly assessing inflammation and coagulation-related indicators helps to more comprehensively reflect the laboratory characteristics of CAP.