Abstract: Objective　To investigate the prognostic value of neutrophil CD64 index combined with Mini Nutrition Assessment Short Form (MNA-SF) score in elderly patients with community-acquired pneumonia. Methods　A total of 116 patients over 60 years old who were hospitalized and diagnosed with community-acquired pneumonia in Department of Geriatric Medicine, The Second People's Hospital of Lianyungang from January 2020 to December 2021 were selected as the research objects. The MNA-SF nutritional score on admission and C-reactive protein (CRP) and neutrophil CD64 index on the first and third day after admission were recorded. According to the severity of pneumonia, the patients were divided into a severe pneumonia group and a common pneumonia group. In the severe pneumonia group, there were 26 males and 17 females, with an age of (84.02±6.86) years old; there were 41 males and 32 females in the common pneumonia group, with an age of (81.89±8.92) years old. At the same time, they were divided into a death group and a survival group according to the 28-day clinical outcome. There were 11 males and 11 females in the death group, with an age of (85.64±6.18) years old; there were 56 males and 38 females in the survival group, with an age of (81.99±8.54) years old. t test, rank sum test, and chi-square test were used. Results　There were statistically significant differences in the Charlson comorbidibility index [(3.47±1.14) vs. (2.19±1.15)], MNA-SF score [(6.33±2.00) vs. (8.74±2.87)], and white blood cell count (WBC) [(13.64±5.89) ×10⁹/L vs. (9.67±4.08) ×10⁹/L, (11.91±5.76) ×10⁹/L vs. (7.98±2.38) ×10⁹/L], CRP [107.14 (72.06, 165.27) mg/L vs. 50.87 (22.98, 91.13) mg/L, 67.93 (36.99, 111.20) mg/L vs. 16.80 (11.40, 26.06) mg/L], and CD64 index [3.11 (1.78, 5.40) vs. 1.27 (1.14, 2.33), 1.80 (1.14, 3.15) vs. 1.03 (0.69, 1.30)] on the first and third day after admission between the severe pneumonia group and the common pneumonia group (all P<0.05). Among the 116 cases, 22 cases died, with a mortality rate of 18.97%. Compared with those in the survival group, the death group had a higher Charlson comorbidity index and a lower MNA-SF score, with statistically significant differences between the two groups (both P<0.05); there were statistically significant differences in the WBC, CRP, and CD64 index on the first and third day after admission between the two groups (all P<0.05). The areas under the curve (AUC) of CRP, CD64 index, and WBC in predicting prognosis were higher on the third day than those on the first day. The AUC of CRP d1+CD64 index d1+WBC d1+MNA-SF score in predicting prognosis was 0.909, the sensitivity was 95.5%, and the specificity was 72.9%; the AUC of CRP d3+CD64 index d3+WBC d3+MNA-SF score was 0.963, the sensitivity was 95.5%, and the specificity was 85.9%. Logistic regression analysis showed that malnutrition, CRP d3, and CD64 index d1 were risk factors for death in elderly patients with community-acquired pneumonia (all P<0.05). The survival curve (K-M curve) analysis showed that the 28-day survival rate in patients with CD64 index d1 <1.55 was significantly higher than that in patients with CD64 index d1 ≥1.55, and the 28-day survival rate of the two groups was statistically significant (96.55% vs. 65.52%, χ²=18.027, P<0.001). Conclusion　Neutrophil CD64 index combined with MNA-SF nutritional score can guide the clinical treatment and predict the prognosis of elderly patients with community-acquired pneumonia.

Key words: Old age, Community-acquired pneumonia, Neutrophil CD64 index, Malnutrition, Prognosis

摘要： 目的　探讨中性粒细胞CD64指数联合微型营养评定量表（MNA-SF）评分对老年社区获得性肺炎患者预后的预测价值。方法　2020年1月至2021年12月在连云港市第二人民医院老年科住院的116例60周岁以上诊断为社区获得性肺炎的患者为研究对象。记录入院时的MNA-SF评分，以及第1、3天的C-反应蛋白（CRP）和中性粒细胞CD64指数。根据肺炎严重程度分为重症肺炎组43例［男26例、女17例，年龄（84.02±6.86）岁］和普通肺炎组73例［男41例、女32例，年龄（81.89±8.92）岁］，根据28 d临床转归分为死亡组22例［男11例、女11例，年龄（85.64±6.18）岁］和存活组94例［男56例、女38例，年龄（81.99±8.54）岁］。采用t检验、秩和检验、χ²检验。结果　重症肺炎组和普通肺炎组Charlson合并症指数［（3.47±1.14）分比（2.19±1.15）分］、MNA-SF评分［（6.33±2.00）分比（8.74±2.87）分］及入院第1天和第3天的白细胞计数（WBC）［（13.64±5.89）×10⁹/L比（9.67±4.08）×10⁹/L、（11.91±5.76）×10⁹/L比（7.98±2.38）×10⁹/L］、CRP［107.14（72.06，165.27）mg/L比50.87（22.98，91.13）mg/L、67.93（36.99，111.20）mg/L比16.80（11.40，26.06）mg/L］和CD64指数［3.11（1.78，5.40）比1.27（1.14，2.33）、1.80（1.14，3.15）比1.03（0.69，1.30）］比较，差异均有统计学意义（均P<0.05）。116例病例中共有22例死亡，病死率为18.97%；与存活组相比，死亡组的Charlson合并症指数更高，而MNA-SF评分更低，两组间差异均有统计学意义（均P<0.05）；两组之间入院第1、3天的WBC、CRP和CD64指数差异均有统计学意义（均P<0.05）。炎症指标CRP、CD64指数及WBC预测预后的曲线下面积（AUC）均为第3天大于第1天；其中CRP d1+CD64指数d1+WBC d1+MNA-SF评分预测预后的AUC为0.909，灵敏度为95.5%，特异度为72.9%；CRP d3+CD64指数d3+WBC d3+MNA-SF评分的AUC为0.963，灵敏度为95.5%，特异度为85.9%。logistic回归分析显示，营养不良、CRP d3和CD64指数d1是老年社区获得性肺炎患者死亡的危险因素（均P<0.05）。生存曲线（K-M曲线）分析显示，CD64指数d1 <1.55者28 d存活率显著高于CD64指数d1≥1.55者，两组28 d存活率差异有统计学意义（96.55%比65.52%，χ²=18.027，P<0.001）。结论　中性粒细胞CD64指数联合MNA-SF评分可指导老年社区获得性肺炎患者临床治疗和预测预后。

关键词: 老年, 社区获得性肺炎, 中性粒细胞CD64指数, 营养不良, 预后