Centre for Heart Lung Innovation, St. Paul's Hospital and Department of Medicine, Division of Respirology, University of British Columbia, Vancouver, Canada.
Centre for Heart Lung Innovation, St. Paul's Hospital and Department of Medicine, Division of Respirology, University of British Columbia, Vancouver, Canada.
Chest. 2022 Feb;161(2):330-344. doi: 10.1016/j.chest.2021.09.036. Epub 2021 Oct 6.
Asthma-COPD overlap (ACO) is a heterogeneous condition that describes patients who show persistent airflow limitation with clinical features that support both asthma and COPD. Although no single consensus definition exists to diagnose this entity, common major criteria include a strong bronchodilator reversibility or bronchial hyperreactivity, a physician diagnosis of asthma, and a ≥ 10-pack-year cigarette smoking history. The prevalence of ACO ranges from 0.9% to 11.1% in the general population, depending on the diagnostic definition used. Notably, patients with ACO experience greater symptom burden, worse quality of life, and more frequent and severe respiratory exacerbations than those with asthma or COPD. The underlying pathophysiologic features of ACO have been debated. Although emerging evidence supports the role of environmental and inhalational exposures in its pathogenesis among patients with a pre-existing airway disease, biomarker profiling and genetic analyses suggest that ACO may be a heterogeneous condition, but with definable characteristics. Early-life factors including childhood-onset asthma and cigarette smoking may interact to increase the risk of airflow obstruction later in life. For treatment options, the population with ACO historically has been excluded from therapeutic trials; therefore strong, evidence-based recommendations are lacking beyond first-line inhaler therapies. Advanced therapies in patients with ACO are selected according to disease phenotypes and are based on extrapolated data from asthma and COPD. Research focused on defining biomarkers and evidence-based treatment options for ACO is needed urgently.
哮喘-慢阻肺重叠(ACO)是一种异质性疾病,描述的是具有支持哮喘和 COPD 的临床特征但持续存在气流受限的患者。尽管目前还没有单一的共识定义来诊断这种疾病,但常见的主要标准包括强烈的支气管扩张剂可逆性或支气管高反应性、医生诊断为哮喘以及 ≥ 10 包年的吸烟史。根据使用的诊断定义,ACO 在普通人群中的患病率为 0.9%至 11.1%。值得注意的是,与哮喘或 COPD 患者相比,ACO 患者的症状负担更大、生活质量更差,并且呼吸恶化的频率和严重程度更高。ACO 的潜在病理生理特征存在争议。虽然新出现的证据支持环境和吸入暴露在有预先存在的气道疾病的患者发病机制中的作用,但生物标志物分析和遗传分析表明,ACO 可能是一种异质性疾病,但具有可定义的特征。生命早期因素,包括儿童期发病的哮喘和吸烟,可能会相互作用,增加以后发生气流阻塞的风险。在治疗选择方面,ACO 人群历来被排除在治疗试验之外;因此,除了一线吸入疗法之外,缺乏强有力的、基于证据的推荐。ACO 患者的高级治疗方法是根据疾病表型选择的,并且基于从哮喘和 COPD 中推断的数据。迫切需要针对 ACO 定义生物标志物和基于证据的治疗选择的研究。