Small airway dysfunction may mediate the association between body mass index and severe asthma exacerbations.

IF 23.8 1区医学 Q1 RESPIRATORY SYSTEM

European Respiratory Journal Pub Date : 2026-09-25 Print Date: 2026-09-01 DOI:10.1183/13993003.00150-2026

Andrea Portacci, Laura Ventura, Francesco Menzella, Remo Poto, Alvise Berti, Carlo Lombardi, Pasquale Comberiati, Giovanna Elisiana Carpagnano, Zuzana Diamant, Ian M Adcock, Brian Lipworth, Omar Usmani, Marcello Cottini, Rory Chan

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引用次数: 0

Abstract

Background: Obesity is associated with poorer asthma outcomes and an increased risk of exacerbations, but the underlying mechanisms remain incompletely understood. Small airway dysfunction (SAD) may represent a key mechanistic link between excess body weight and adverse asthma outcomes.

Methods: In this multicentre observational study, adult patients with asthma underwent clinical characterisation, spirometry and impulse oscillometry (IOS). SAD was defined using a composite criterion based on small airway resistance (frequency dependence of resistance between 5 and 20 Hz (R _5-20)), reactance area (AX) and ratio of peripheral airway to total airway resistance ((R _5-20)/R ₅). Associations between body mass index (BMI), SAD and severe asthma exacerbations were assessed using multivariable regression models. Non-linear relationships were explored using generalised additive models, and mediation analyses quantified the contribution of SAD to the obesity-exacerbation association.

Results: Among 1169 patients, IOS-defined SAD was significantly more prevalent in individuals with BMI ≥30 kg·m^-2. Increasing BMI was associated with worse IOS parameters (p<0.0001), following a non-linear pattern with steeper deterioration beyond BMI values of ∼28-30 kg·m^-2. SAD was independently associated with obesity (adjusted OR 2.11, 95% CI 1.56-2.86) and with severe asthma exacerbations in the previous year (adjusted OR 2.01, 95% CI 1.53-2.65) (both p<0.0001). Mediation analyses showed that SAD accounted for 26-41% of the association between obesity and exacerbation risk (p=0.004 and p=0.03). Spirometry indices provided limited additional information.

Conclusion: Oscillometry-defined SAD represents a non-linear functional trait underlying the association between obesity and severe asthma exacerbations, supporting its clinical relevance in obese patients with asthma and identifying SAD as a potential treatable trait.

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小气道功能障碍可能介导体重指数与严重哮喘发作之间的关联。

背景：肥胖与哮喘预后较差和加重风险增加有关，但其潜在机制仍不完全清楚。小气道功能障碍（SAD）可能是超重和不良哮喘结局之间的关键机制联系。方法：在这项多中心观察性研究中，对成年哮喘患者进行临床特征、肺活量测定和脉冲振荡测定（IOS）。采用基于外周气道阻力（R5-20）、电抗面积（AX）和外周气道与总气道阻力(R5-20)/R5的复合标准定义SAD。使用多变量回归模型评估体重指数（BMI）、SAD和严重哮喘加重之间的关系。利用广义加性模型探讨了非线性关系，并通过中介分析量化了SAD对肥胖-恶化关联的贡献。结果：在1169例患者中，ios定义的SAD在BMI≥30 kg·m-2的个体中更为普遍。BMI增加与较差的振荡参数相关（p-2）。SAD与肥胖（校正OR 2.11, 95% CI 1.56-2.86）和前一年的严重哮喘发作（校正OR 2.01, 95% CI 1.53-2.65）独立相关。解释：振荡测量定义的小气道功能障碍（SAD）代表了肥胖和严重哮喘发作之间关联的非线性功能特征，支持其在肥胖哮喘患者中的临床相关性，并确定SAD是一种潜在的可治疗特征。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

European Respiratory Journal 医学-呼吸系统

CiteScore

27.50

自引率

3.30%

发文量

345

审稿时长

2-4 weeks

期刊介绍： The European Respiratory Journal (ERJ) is the flagship journal of the European Respiratory Society. It has a current impact factor of 24.9. The journal covers various aspects of adult and paediatric respiratory medicine, including cell biology, epidemiology, immunology, oncology, pathophysiology, imaging, occupational medicine, intensive care, sleep medicine, and thoracic surgery. In addition to original research material, the ERJ publishes editorial commentaries, reviews, short research letters, and correspondence to the editor. The articles are published continuously and collected into 12 monthly issues in two volumes per year.