Almeshari Mohammed A, Alobaidi Nowaf Y, Stockley James A, Stockley Robert A, Nagakumar Prasad, Sutton Benjamin Paul, Sapey Elizabeth
Rehabilitation Health Sciences Department, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia.
Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK.
J Asthma Allergy. 2025 Mar 6;18:377-389. doi: 10.2147/JAA.S489893. eCollection 2025.
Physiological evidence of small airways dysfunction (SAD) is present in some patients with asthma and is associated with poor disease control. It is unclear if this represents a distinct phenotype of asthma or if it is an early manifestation of the disease. The study aimed to evaluate SAD in asthma and its clinical associations.
A retrospective analysis of routinely collected health data obtained from adults referred for routine spirometric assessment as part of their clinical management. The Maximal Mid-Expiratory Flow (MMEF) z-scores were used to assess the prevalence and association factors for SAD. Pre- and post-bronchodilator data of MMEF and FEV in patients with and without SAD or airflow obstruction (AO) were analysed.
A total of 1094 patients were included. 366 (33.5%) had evidence of SAD of whom 261 (71.3%) also had AO. Current smokers were at an increased risk of having SAD (OR: 2.05; 95% CI: 1.43-2.93). 214 patients had Bronchodilator response (BDR) data with 157 (73.4%) demonstrating BDR for MMEF and 121 (56.5%) for FEV. SAD at baseline was associated with a significant BDR for FEV (OR of 3.59 (95% CI: 1.77-7.57)) and MMEF (OR of 2.89 (95% CI: 1.41-5.95)). Males were less likely to have a positive BDR for MMEF than females (OR of 0.46; 95% CI: 0.24-0.89).
SAD is common in asthma and is related to the presence of AO, cigarette smoking and is associated with increased BDR for both FEV and MMEF. The assessment of SAD in routine clinical practice may help identify airway impairment early for the initiation of targeted therapies.
小气道功能障碍（SAD）的生理证据在部分哮喘患者中存在，且与疾病控制不佳相关。目前尚不清楚这是哮喘的一种独特表型，还是疾病的早期表现。本研究旨在评估哮喘中的SAD及其临床关联。
对作为临床管理一部分而接受常规肺量计评估的成年人的常规收集的健康数据进行回顾性分析。最大呼气中期流量（MMEF）z评分用于评估SAD的患病率和相关因素。分析了有或无SAD或气流阻塞（AO）患者的支气管扩张剂使用前后MMEF和FEV的数据。
共纳入1094例患者。366例（33.5%）有SAD证据，其中261例（71.3%）也有AO。当前吸烟者患SAD的风险增加（比值比：2.05；95%置信区间：1.43 - 2.93）。214例患者有支气管扩张剂反应（BDR）数据，其中157例（73.4%）MMEF显示有BDR，121例（56.5%）FEV显示有BDR。基线时的SAD与FEV（比值比为3.59（95%置信区间：1.77 - 7.57））和MMEF（比值比为2.89（95%置信区间：1.41 - 5.95））的显著BDR相关。男性MMEF的BDR阳性可能性低于女性（比值比为0.46；95%置信区间：0.24 - 0.89）。
SAD在哮喘中常见，与AO的存在、吸烟相关，且与FEV和MMEF的BDR增加有关。在常规临床实践中评估SAD可能有助于早期识别气道损伤，以便启动靶向治疗。
