LungenClinic Grosshansdorf, Airway Research Center North, German Center for Lung Research, Grosshansdorf, Germany.
Department of Pneumology and Critical Care Medicine, Thoraxklinik, University of Heidelberg, Translational Lung Research Center Heidelberg, German Center for Lung Research, Heidelberg, Germany; Department of Biomedical Informatics, Heinrich-Lanz-Center, University Medical Center Mannheim, Mannheim, Germany.
J Allergy Clin Immunol Pract. 2021 Sep;9(9):3359-3368.e1. doi: 10.1016/j.jaip.2021.04.035. Epub 2021 Apr 27.
Little is known about the role of small airway dysfunction (SAD) and its complex relation with asthma control and physical activity (PA).
To investigate the interrelations among SAD, risk factors for asthma severity, symptom control, and PA.
We assessed SAD by impulse oscillometry and other sophisticated lung function measures including inert gas washout in adults with asthma (mild to moderate, n = 140; severe, n = 128) and 69 healthy controls from the All Age Asthma Cohort. We evaluated SAD prevalence and its interrelation with risk factors for asthma severity (older age, obesity, and smoking), type 2 inflammation (sputum and blood eosinophils, fractional exhaled nitric oxide), systemic inflammation (high-sensitivity C-reactive protein), asthma control (AC), and PA (accelerometer for 1 week). We applied a clinical model based on structural equation modeling that integrated causal pathways among these clinical variables.
The prevalence of SAD ranged from 75% to 90% in patients with severe asthma and from 53% to 64% in mild to moderate asthma. Severe SAD was associated with poor AC and low PA. Structural equation modeling indicated that age, obesity, obesity-related systemic inflammation, T2 inflammation, and smoking are independent predictors of SAD. Small airway dysfunction was the main determinant factor of AC, which in turn affected PA. Obesity affected AC directly and through its contribution to SAD and low PA. In addition, PA had bidirectional associations with obesity, SAD, and AC. Structural equation modeling also indicated interrelations among distal airflow limitation, air trapping, and ventilation heterogeneity.
Small airway dysfunction is a highly prevalent key feature of asthma that interrelates a spectrum of distal lung function abnormalities with risk factors for asthma severity, asthma control, and physical activity.
人们对小气道功能障碍（SAD）的作用及其与哮喘控制和体力活动（PA）的复杂关系知之甚少。
研究 SAD 与哮喘严重程度的危险因素、症状控制和 PA 之间的相互关系。
我们通过脉冲震荡法评估了哮喘患者（轻度至中度，n=140；重度，n=128）和 69 名健康对照者的 SAD 及其他复杂肺功能指标，包括惰性气体清除率。我们评估了 SAD 的患病率及其与哮喘严重程度的危险因素（年龄较大、肥胖和吸烟）、2 型炎症（痰和血嗜酸性粒细胞、呼出的一氧化氮分数）、系统性炎症（高敏 C 反应蛋白）、哮喘控制（AC）和 PA（1 周加速度计）之间的关系。我们应用了一种基于结构方程模型的临床模型，该模型整合了这些临床变量之间的因果途径。
重度哮喘患者 SAD 的患病率为 75%90%，轻度至中度哮喘患者为 53%64%。严重 SAD 与 AC 差和 PA 低有关。结构方程模型表明，年龄、肥胖、肥胖相关的系统性炎症、2 型炎症和吸烟是 SAD 的独立预测因素。小气道功能障碍是 AC 的主要决定因素，AC 反过来又影响 PA。肥胖直接影响 AC，并通过对 SAD 和低 PA 的影响间接影响 AC。此外，PA 与肥胖、SAD 和 AC 之间存在双向关联。结构方程模型还表明，远端气流受限、空气滞留和通气异质性之间存在相互关系。
SAD 是哮喘的一个高度普遍的关键特征，它将一系列远端肺功能异常与哮喘严重程度的危险因素、哮喘控制和体力活动联系起来。
