基线NLR对重症肺炎患者28天预后的预测价值：一项单中心回顾性队列研究

Predictive Value of Baseline NLR for 28-Day Prognosis of Patients with Severe Pneumonia: A Single-Center Retrospective Cohort Study

摘要: 目的：探讨入住ICU时基线中性粒细胞与淋巴细胞比值(NLR)对重症肺炎患者28天预后的预测价值。方法：采用单中心回顾性队列研究设计，纳入2023年1月至2026年5月珠海市中西医结合医院重症医学科收治的80例重症肺炎患者，根据28天生存状态分为存活组(64例)和死亡组(16例)。比较两组患者基线资料及临床特征，采用受试者工作特征(ROC)曲线评价基线NLR、急性生理学与慢性健康状况评分II (APACHE II)及格拉斯哥昏迷评分(GCS)对28天死亡的预测价值，采用二元Logistic回归分析28天死亡的影响因素。结果：80例患者28天病死率为20.00% (16/80)。死亡组GCS评分低于存活组[4.50 (3.00, 6.75)分比7.50 (5.00, 10.00)分]，APACHE II评分高于存活组[(31.56 ± 10.79)分比(23.77 ± 7.75)分]，PCT水平及入院当天机械通气、血管活性药物、肾脏替代治疗使用率高于存活组，差异均有统计学意义(均P < 0.05)；死亡组基线NLR高于存活组[26.05 (17.04, 37.76)比18.21 (8.36, 33.78)]，但差异无统计学意义(P > 0.05)。ROC曲线分析显示，基线NLR预测28天死亡的曲线下面积(AUC)为0.589 (95% CI 0.433~0.750)，最佳截断值为16.42，对应敏感度81.3%、特异度45.3%；高NLR组(≥16.42) 28天病死率高于低NLR组[27.1% (13/48)比9.4% (3/32)，OR = 3.59，P = 0.052]。多因素Logistic回归分析显示，APACHE II评分是重症肺炎患者28天死亡的独立危险因素(OR = 1.096, 95% CI 1.010~1.188, P = 0.027)。结论：重症肺炎患者基线NLR升高与28天死亡风险增加的趋势相关，以16.42为截断值具有较高敏感度，可作为早期风险筛查的辅助指标；但其独立预测价值有限。APACHE II评分是28天死亡的独立危险因素，临床宜以APACHE II评分等经典病情评估工具为主，联合GCS评分与NLR综合判断患者预后。

Abstract: Objective: To investigate the predictive value of the baseline neutrophil-to-lymphocyte ratio (NLR) at ICU admission for the 28-day prognosis of patients with severe pneumonia. Methods: A single-center retrospective cohort study was conducted. A total of 80 patients with severe pneumonia admitted to the Department of Critical Care Medicine, Zhuhai Hospital of Integrated Traditional Chinese and Western Medicine, from January 2023 to May 2026 were enrolled. According to the 28-day survival status, patients were divided into a survival group (n = 64) and a death group (n = 16). Baseline data and clinical characteristics were compared between the two groups. The predictive values of baseline NLR, Acute Physiology and Chronic Health Evaluation II (APACHE II) score, and Glasgow Coma Scale (GCS) score for 28-day mortality were evaluated using the receiver operating characteristic (ROC) curve analysis. Binary logistic regression analysis was performed to identify risk factors for 28-day mortality. Results: The 28-day mortality rate of the 80 patients was 20.00% (16/80). The GCS score of the death group was lower than that of the survival group [4.50 (3.00, 6.75) vs. 7.50 (5.00, 10.00) points], while the APACHE II score [(31.56 ± 10.79) vs. (23.77 ± 7.75) points], procalcitonin (PCT) level, and the utilization rates of mechanical ventilation, vasoactive agents, and renal replacement therapy on the day of admission were higher in the death group than in the survival group, with statistically significant differences (all P < 0.05). The baseline NLR of the death group was higher than that of the survival group [26.05 (17.04, 37.76) vs. 18.21 (8.36, 33.78)], but the difference was not statistically significant (P > 0.05). ROC curve analysis showed that the area under the curve (AUC) of baseline NLR for predicting 28-day mortality was 0.589 (95% CI 0.433~0.750), with an optimal cut-off value of 16.42, corresponding to a sensitivity of 81.3% and a specificity of 45.3%. The 28-day mortality rate of the high-NLR group (≥16.42) was higher than that of the low-NLR group [27.1% (13/48) vs. 9.4% (3/32), OR = 3.59, P = 0.052]. Multivariate logistic regression analysis revealed that the APACHE II score was an independent risk factor for 28-day mortality in patients with severe pneumonia (OR = 1.096, 95% CI 1.010~1.188, P = 0.027). Conclusion: Elevated baseline NLR in patients with severe pneumonia is associated with a trend toward increased 28-day mortality risk. With a cut-off value of 16.42, NLR demonstrates high sensitivity and may serve as an auxiliary indicator for early risk screening; however, its independent predictive value is limited. The APACHE II score is an independent risk factor for 28-day mortality. In clinical practice, classic disease severity assessment tools such as the APACHE II score should remain the mainstay, combined with the GCS score and NLR for comprehensive prognosis evaluation.