Abstract:

Objective　To investigate the value of the ratio of neutrophil to platelet count in the prediction of prognosis of patients with severe pneumonia. Methods　One hundred and forty-seven elderly patients with complete data diagnosed as severe pneumonia at Jinqiu Hospital from December 2018 to December 2020 were collected for the retrospective study, including 87 males and 60 females who were 65-85 years old. Taking 28 days of treatment as the observation period, the patients were divided into a survival group (118 cases) and a death group (29 cases) according to the situation after the treatment. The general data of the enrolled patients, such as gender, age, disease history, etc., were collected and recorded. The white blood cell count (WBC), C-reactive protein (CRP), procalcitonin (PCT), absolute number of neutrophils (NEUT), platelet count (PLT), and other indicators were detected in all the patients; the NPR(NEUT/PLT) was calculated. The basic data, medical history, acute physiology, and chronic health evaluation Ⅱ (APACHE Ⅱ) scores, WBC, CRP, PCT, PLT, Lac, NPR×100, and other indicators of the two groups before and after the treatment were compared and analyzed. The meaningful indicators screened by single factor analysis were analyzed by multifactor logistic regression analysis. NPR×100 was analyzed by receiver operating characteristic curve (ROC). χ² and t tests were applied. Results　The PLT was much higher and the levels of NPR×100, PCT, and Lac and APACHE Ⅱ score were significantly lower in the survival group than in the death group [(157.73±16.99)×10⁹/L vs. (120.48±14.06)×10⁹/L, (9.00±4.08) vs. (15.78±6.26), (12.20±3.09) ng/L vs. (14.06±3.04) ng/L, (1.04±0.27) mmol/L vs. (1.73±0.27 )mmol/L, and (22.25±5.17) vs. (29.79±4.90)], with statistical differences (t=10.916, 7.139, 2.913, 12.330, and 7.107; all P<0.05). Multivariate logistic regression analysis showed that PLT, NPR×100, and Lac were important factors for monitoring the patients' prognosis (P=0.003, 0.007, and 0.008). The area under the ROC of NPR×100 for predicting the patients' prognosis within 24 hours after admission was 0.858; the optimal cut-off value of NPR was 12.960; the sensitivity was 0.729; the specificity was 0.887; the Jordan index was 0.616. Conclusions　High APACHE Ⅱ score, high NPR, high PCT, high Lac, and low PLT can all indicate poor prognosis of patients with severe pneumonia, with good predictive value for the disease prognosis. PLT, NPR, and Lac can be used as independent risk factors for predicting 28 d mortality. NPR has a good sensitivity and a good specificity in predicting the death risk of patients with severe pneumonia, so it is worthy of further study.

Key words:

Severe pneumonia, Neutrophil to platelet count ratio, Prognosis

摘要：

目的　探讨中性粒细胞与血小板计数比值对重症肺炎患者预后的预测价值。方法　收集辽宁省金秋医院2018年12月至2020年12月诊断为重症肺炎治疗的具有完整数据资料的老年患者147例进行回顾性研究，其中男87例，女60例，年龄65～85岁，以治疗28 d为观察期，根据治疗后情况将患者分为生存组和死亡组，其中生存组118例，死亡组29例。收集并记录入组患者一般资料，如性别、年龄、疾病史等。检测患者体内白细胞计数（WBC）、C-反应蛋白（CRP）、降钙素原（PCT）、中性粒细胞绝对数（NEUT）、血小板计数（PLT）等指标，并计算NPR（NEUT/PLT）。对两组患者治疗前后的基础资料、病史、急性生理与慢性健康评价Ⅱ（APACHE Ⅱ） 评分、WBC、CRP、PCT、PLT、Lac、NPR×100等指标，单因素筛查有意义指标行多因素logistic 回归分析。对NPR×100采用受试者工作特征曲线（ROC）分析。统计学方法采用χ²检验、t检验。结果　生存组PLT水平明显高于死亡组［（157.73±16.99）×10⁹/L比（120.48±14.06）×10⁹/L］，同时生存组NPR×100、PCT、Lac、APACHE Ⅱ评分明显低于死亡组［（9.00±4.08）比（15.78±6.26）、（12.20±3.09）ng/L比（14.06±3.04）ng/L、（1.04±0.27）mmol/L比（1.73±0.27）mmol/L、（22.25±5.17）分比（29.79±4.90）分］，差异均有统计学意义（t=10.916、7.139、2.913、12.330、7.107，均P<0.05）。多因素logistic 回归分析示PLT、NPR×100、Lac是监测重症肺炎患者预后的重要因素（P=0.003、0.007、0.008），患者入院24 h内NPR×100值对重症肺炎预后判断价值的ROC曲线下面积为0.858，NPR最佳界值为12.960，灵敏度0.729，特异度0.887，约登指数为0.616。结论　高APACHEⅡ评分、高NPR、高PCT、高Lac及低PLT均可提示重症肺炎患者预后不良，对疾病预后有较好的预测价值。PLT、NPR及Lac可作为预测患者28 d病死率的独立危险因素。NPR在预测重症肺炎患者死亡风险方面具有较好的灵敏度和特异度，值得进行深入研究。

关键词:

重症肺炎, 中性粒细胞与血小板计数比值, 预后