Abstract: Objective　This study aims to determine whether nutritional status is a risk factor contributing to the severity of pneumonia in elderly patients with community-acquired pneumonia （CAP） and to investigate the predictive value of mini nutritional assessment （MNA） in severe pneumonia.Methods　A total of 131 elderly patients with community-acquired pneumonia hospitalized in the General Department of Beijing Chao-yang Hospital （from 2016 to 2017） were enrolled.All patients were divided into non-severe pneumonia group （n=77） and severe pneumonia group （n=54）．The pneumonia data including clinical factors and laboratory data were recorded.Multivariable Logistic stepwise regression analysis was performed to investigate the risk factors of patients with severe pneumonia，and the receiver operating characteristic（ROC） curve to assess the predictive value of MNA score in severe pneumonia.Results　Of 131 elderly patients with CAP，54 subjects were severe pneumonia （41.2%），and 45 had malnutrition （34.4%）．Age，incidence of malnutrition，proportion of CAP with chronic obstructive pulmonary disease，proportion of CAP with chronic heart failure，proportion of CAP with cerebrovascular disease，oxygen partial pressure，serum creatinine level and blood urea nitrogen level in two groups were significantly different （P<0.05）．According to the results of multivariable Logistic stepwise regression analysis，malnutrition，CAP combining chronic obstructive pulmonary disease and CAP combining chronic heart failure were risk factors of severe pneumonia （P<0.05）．The accuracy of MNA score predicted severe pneumonia was 0.804 〔95%CI（0.724，0.884）〕 as measured by the area under the ROC curve.The best cut-off point in MNA score was 17.5 （17 for malnutrition） and the sensitivity and specificity rate were 86.3% and 66.7%.Conclusion　Malnutrition may be considered as an independent factor of severe pneumonia in elderly patients with community-acquired pneumonia，and MNA score has predictive value for severe pneumonia.

Key words: Community-acquired pneumonia, Aged, Malnutrition, Severity of pneumonia, Severe pneumonia

摘要： 目的　探讨老年社区获得性肺炎患者营养状况对肺炎严重程度的影响以及微型营养评估法（MNA）评分对重症肺炎的预测价值。方法　选取2016—2017年在北京朝阳医院综合科住院的131例老年社区获得性肺炎患者为研究对象。根据患者肺炎严重程度，将所有患者分为非重症肺炎组（n=77）和重症肺炎组（n=54）。收集患者一般资料和实验室检查指标。采用多因素Logistic逐步回归分析探讨患者发生重症肺炎的影响因素，采用受试者工作特征（ROC）曲线评估MNA评分对重症肺炎的预测价值。结果　131例老年社区获得性肺炎患者中，重症肺炎54例（41.2%），营养不良45例（34.4%）。两组患者年龄、营养不良发生率、合并慢性阻塞性肺疾病比例、合并慢性心力衰竭比例、合并陈旧脑血管病比例、血气分析氧分压、血肌酐、血尿素氮比较，差异有统计学意义（P<0.05）。是否营养不良、是否合并慢性阻塞性肺疾病、是否合并慢性心力衰竭是老年社区获得性肺炎患者发生重症肺炎的影响因素（P<0.05）。MNA评分预测社区老年患者发生重症肺炎的ROC曲线下面积为0.804〔95%CI（0.724，0.884）〕。MNA评分预测重症肺炎的最佳截断点为17.5分（MNA评分判定营养不良标准为17分），对应的灵敏度和特异度分别为86.3%和66.7%。结论　营养不良为老年社区获得性肺炎患者发生重症肺炎的独立影响因素，MNA评分对重症肺炎发生有一定的预测价值。

关键词: 社区获得性肺炎, 老年人, 营养不良, 肺炎严重程度, 重症肺炎