Kobayashi Seiichi, Hanagama Masakazu, Yamanda Shinsuke, Ishida Masatsugu, Yanai Masaru
Department of Respiratory Medicine, Japanese Red Cross Ishinomaki Hospital, Ishinomaki, Japan.
Int J Chron Obstruct Pulmon Dis. 2016 Sep 7;11:2117-2123. doi: 10.2147/COPD.S113647. eCollection 2016.
The clinical phenotypes and underlying mechanisms of asthma-COPD overlap syndrome (ACOS) remain elusive. This study aimed to investigate a comparison of COPD patients with and without ACOS, focusing on inflammatory biomarkers, in an outpatient COPD cohort.
We conducted a cross-sectional study analyzing prospectively collected data from the Ishinomaki COPD Network registry. All participants were diagnosed with COPD, confirmed by using spirometry, and were aged 40-90 years and former smokers. Patients with features of asthma including both variable respiratory symptoms and variable expiratory airflow limitation were identified and defined as having ACOS. Then, the inflammatory biomarkers such as fractional exhaled nitric oxide level, blood eosinophil count and percentage, total immunoglobulin E (IgE) level, and presence of antigen-specific IgE were evaluated.
A total of 257 patients with COPD were identified, including 37 (14.4%) with ACOS. Patients with ACOS tended to be younger, have a shorter smoking history, and use more respiratory medications, especially inhaled corticosteroids and theophylline. Mean fractional exhaled nitric oxide level was significantly higher in those with ACOS than in those without ACOS (38.5 parts per billion [ppb] vs 20.3 ppb, <0.001). Blood eosinophil count and percentage were significantly increased in those with ACOS (295/mm vs 212/mm, =0.032; 4.7% vs 3.2%, =0.003, respectively). Total IgE level was also significantly higher, and presence of antigen-specific IgE was observed more frequently in patients with ACOS. Receiver operating characteristic curve analysis indicated that the sensitivity and specificity of these biomarkers were relatively low, but combinations of these biomarkers showed high specificity for ACOS diagnosis.
These results provide evidence that these inflammatory biomarkers can be used to support the diagnosis of ACOS.
哮喘-慢性阻塞性肺疾病重叠综合征（ACOS）的临床表型及潜在机制仍不明确。本研究旨在对慢性阻塞性肺疾病门诊队列中合并和不合并ACOS的患者进行比较，重点关注炎症生物标志物。
我们进行了一项横断面研究，分析前瞻性收集的石卷慢性阻塞性肺疾病网络登记处的数据。所有参与者均通过肺量计确诊为慢性阻塞性肺疾病，年龄在40 - 90岁之间，且均为既往吸烟者。具有哮喘特征（包括可变的呼吸道症状和可变的呼气气流受限）的患者被识别并定义为患有ACOS。然后，评估炎症生物标志物，如呼出一氧化氮分数水平、血液嗜酸性粒细胞计数及百分比、总免疫球蛋白E（IgE）水平以及抗原特异性IgE的存在情况。
共识别出257例慢性阻塞性肺疾病患者，其中37例（14.4%）患有ACOS。患有ACOS的患者往往更年轻，吸烟史更短，使用更多的呼吸药物，尤其是吸入性糖皮质激素和茶碱。ACOS患者的平均呼出一氧化氮分数水平显著高于无ACOS患者（38.5 ppb对20.3 ppb，<0.001）。ACOS患者的血液嗜酸性粒细胞计数及百分比显著升高（分别为295/mm对212/mm，P = 0.032；4.7%对3.2%，P = 0.003）。ACOS患者的总IgE水平也显著更高，且抗原特异性IgE的存在更为常见。受试者工作特征曲线分析表明，这些生物标志物的敏感性和特异性相对较低，但这些生物标志物的组合对ACOS诊断具有较高的特异性。
这些结果提供了证据，表明这些炎症生物标志物可用于支持ACOS的诊断。
