SH Ho Research Center in Respiratory Diseases, Division of Respiratory Medicine, Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong.
Respirology. 2020 Mar;25(3):259-266. doi: 10.1111/resp.13660. Epub 2019 Aug 6.
Airway inflammation accompanying exacerbations varies among individuals with some having neutrophilic, while others showing eosinophilic inflammation. This study assessed the cut-off values of blood eosinophil count for identifying subjects with longer hospital length of stay (LOS) with acute exacerbations of chronic obstructive pulmonary disease (AECOPD).
Patients were recruited at presentation to the hospital with an AECOPD. Complete blood picture with differential count was taken on admission. Patients were treated with a standard course of systemic corticosteroid and antibiotic and evaluated at 8 weeks post-exacerbation for lung function measurement and 6-min walk. They were followed up in 1 year for any readmissions or mortality. Cut-off values of eosinophils for assessment of longer LOS were calculated using receiver operating characteristic (ROC) curve analysis.
A total of 346 patients with admission eosinophil count were included in the analysis (333 (96.2%) were males; mean ± SD age: 74.9 ± 7.8 years; mean forced expiratory volume in 1 s (FEV ): 43.4 ± 16.3% predicted). The median (interquartile range (IQR)) of the absolute peripheral eosinophil count, percent eosinophil count and LOS were 0.11 (0.25) × 10 /L, 1 (3) % and 5 (7) days, respectively. Using the median LOS of ≥5 days as the cut-off, ROC analysis of the cut-off value of eosinophil count associated with longer LOS was at <2% (area under the curve (AUC): 0.666, P < 0.001) while absolute eosinophil count was at <0.144 × 10 /L (AUC: 0.645, P < 0.001). These eosinophil cut-off values could predict longer LOS independent of age, lung function and previous hospital admissions, but had no association with readmissions for AECOPD and mortality at 12 months.
An eosinophil value of <0.144 × 10 /L on admission or <2% was associated with longer hospital LOS for AECOPD.
伴有加重的气道炎症在个体之间存在差异，有些表现为中性粒细胞炎症，而另一些则表现为嗜酸性粒细胞炎症。本研究评估了血嗜酸性粒细胞计数的截断值，以确定慢性阻塞性肺疾病（COPD）急性加重（AECOPD）患者的住院时间（LOS）较长。
在 AECOPD 住院时招募患者。入院时进行全血细胞计数和分类计数。患者接受标准疗程的全身皮质类固醇和抗生素治疗，并在 AECOPD 后 8 周进行肺功能测量和 6 分钟步行评估。在 1 年内对任何再入院或死亡进行随访。使用接受者操作特征（ROC）曲线分析计算嗜酸性粒细胞截断值，以评估较长 LOS。
共纳入 346 例入院时嗜酸性粒细胞计数患者进行分析（333 例（96.2%）为男性；平均年龄（标准差）：74.9±7.8 岁；平均用力呼气量（FEV1）：43.4±16.3%预测值）。绝对外周血嗜酸性粒细胞计数、嗜酸性粒细胞百分比和 LOS 的中位数（四分位间距（IQR））分别为 0.11（0.25）×109/L、1（3）%和 5（7）天。使用中位 LOS≥5 天作为截断值，嗜酸性粒细胞计数与较长 LOS 相关的截断值的 ROC 分析结果为<2%（曲线下面积（AUC）：0.666，P<0.001），而绝对嗜酸性粒细胞计数为<0.144×109/L（AUC：0.645，P<0.001）。这些嗜酸性粒细胞截断值可独立于年龄、肺功能和既往住院情况预测较长的 LOS，但与 12 个月时 AECOPD 的再入院和死亡率无关。
入院时嗜酸性粒细胞值<0.144×109/L 或<2%与 AECOPD 的住院时间较长有关。
