M. Tommola and colleagues raise an important and hotly debated diagnostic criterion of asthma–chronic obstructive pulmonary disease overlap syndrome (ACOS): an age threshold of 40 years for the asthma component of ACOS. We agree with their comment that asthma can develop later in life and these patients may respond well to inhaled corticosteroids and novel biologics, similar to those with childhood-onset asthma [1]. Thus, in the roundtable consensus report [2], we suggested that the asthma component of ACOS could be fulfilled by a clinical diagnosis of asthma before age 40 years or in those without a clinical diagnosis of asthma before 40 years by demonstrating an improvement in forced expiratory volume in 1 s (FEV1) of ≥400 mL following short-acting β2-agonist therapy. While a significant bronchodilatory response (BDR) is a common feature in both asthma and chronic obstructive pulmonary disease (COPD) [3], it is very unusual for COPD patients to demonstrate a BDR of ≥400 mL in FEV1 without a concomitant diagnosis of asthma [4]. To further improve the specificity of the asthma component of ACOS, we also suggested that in addition to all three major criteria, patients fulfil at least one of the three minor criteria: 1) a history of atopy or allergic rhinitis; 2) a BDR of ≥200 mL in FEV1 on two separate visits; or 3) peripheral eosinophil count of ≥300 cells per μL. While none of these criteria has been validated in ACOS, we believe that these criteria are clinically workable and may be useful in identifying patients with asthma with reasonable precision. Future work will be needed to refine these criteria based on high-grade data. While the ACOS criteria have not been validated, they are clinically workable and may identify asthma precisely http://ow.ly/qLSL30cOh4Z

中文翻译：

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如果使用哮喘的年龄限制为 40 岁，则担心会漏诊哮喘-COPD 重叠综合征

M. Tommola 及其同事提出了一个重要且备受争议的哮喘-慢性阻塞性肺疾病重叠综合征 (ACOS) 诊断标准：ACOS 哮喘成分的年龄阈值为 40 岁。我们同意他们的意见，即哮喘可在生命后期发展，这些患者可能对吸入性皮质类固醇和新型生物制剂反应良好，类似于儿童期哮喘 [1]。因此，在圆桌会议共识报告 [2] 中，我们建议在 40 岁之前临床诊断为哮喘或在 40 岁之前没有临床诊断哮喘的患者中，通过证明强迫症的改善可以满足 ACOS 的哮喘成分短效 β2 激动剂治疗后 1 秒呼气量 (FEV1) ≥ 400 mL。虽然显着的支气管扩张反应 (BDR) 是哮喘和慢性阻塞性肺疾病 (COPD) 的共同特征 [3]，但 COPD 患者在 FEV1 中表现出 ≥ 400 mL 的 BDR 而没有同时诊断出哮喘是非常罕见的[4]。为了进一步提高 ACOS 哮喘成分的特异性，我们还建议，除了所有三个主要标准外，患者还至少满足三个次要标准中的一个：1）特应性或过敏性鼻炎病史；2) 两次单独就诊时 FEV1 的 BDR ≥ 200 mL；或 3) 外周嗜酸性粒细胞计数≥300 个细胞/μL。虽然这些标准都没有在 ACOS 中得到验证，但我们相信这些标准在临床上是可行的，并且可能有助于以合理的精度识别哮喘患者。未来的工作将需要根据高等级数据完善这些标准。虽然 ACOS 标准尚未得到验证，但它们在临床上是可行的，并且可以准确地识别哮喘 http://ow.ly/qLSL30cOh4Z