Chongqing Key Laboratory of Pediatrics, International Science and Technology Cooperation base of Child Development and Critical Disorders, Department of Children's Hospital of Chongqing Medical, Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Department of Clinical Laboratory center, University of Education, 400014, Chongqing, China.
National Clinical Research Center for Child Health and Disorders, Department of Respiratory Medicine, Children's Hospital of Chongqing Medical University, Chongqing, China.
BMC Pulm Med. 2023 Jun 20;23(1):219. doi: 10.1186/s12890-023-02515-3.
Small airways are the major sites of inflammation and airway remodeling in all severities of asthma patients. However, whether small airway function parameters could reflect the airway dysfunction feature in preschool asthmatic children remain unclear. We aim to investigate the role of small airway function parameters in evaluating airway dysfunction, airflow limitation and airway hyperresponsiveness (AHR).
Eight hundred and fifty-one preschool children diagnosed with asthma were enrolled retrospectively to investigate the characteristics of small airway function parameters. Curve estimation analysis was applied to clarify the correlation between small and large airway dysfunction. Spearman's correlation and receiver-operating characteristic (ROC) curves were employed to evaluate the relationship between small airway dysfunction (SAD) and AHR.
The prevalence of SAD was 19.5% (166 of 851) in this cross-sectional cohort study. Small airway function parameters (FEF25-75%, FEF50%, FEF75%) showed strong correlations with FEV% (r = 0.670, 0.658, 0.609, p<0.001, respectively), FEV/FVC% (r = 0.812, 0.751, 0.871, p<0.001, respectively) and PEF% (r = 0.626, 0.635, 0.530, p<0.01, respectively). Moreover, small airway function parameters and large airway function parameters (FEV%, FEV/FVC%, PEF%) were curve-associated rather than linear-related (p<0.001). FEF25-75%, FEF50%, FEF75% and FEV% demonstrated a positive correlation with PC (r = 0.282, 0.291, 0.251, 0.224, p<0.001, respectively). Interestingly, FEF25-75% and FEF50% exhibited a higher correlation coefficient with PC than FEV% (0.282 vs. 0.224, p = 0.031 and 0.291 vs. 0.224, p = 0.014, respectively). ROC curve analysis for predicting moderate to severe AHR showed that the area under the curve (AUC) was 0.796, 0.783, 0.738, and 0.802 for FEF25-75%, FEF50%, FEF75%, and the combination of FEF25-75% and FEF75%, respectively. When Compared to children with normal lung function, patients with SAD were slightly older, more likely to have a family history of asthma and airflow obstruction with lower FEV% and FEV/FVC%, lower PEF% and more severe AHR with lower PC ( all p<0.05).
Small airway dysfunction is highly correlated with large airway function impairment, severe airflow obstruction and AHR in preschool asthmatic children. Small airway function parameters should be utilized in the management of preschool asthma.
小气道是所有严重程度哮喘患者炎症和气道重塑的主要部位。然而，小气道功能参数是否能反映学龄前哮喘儿童的气道功能障碍特征尚不清楚。我们旨在研究小气道功能参数在评估气道功能障碍、气流受限和气道高反应性（AHR）中的作用。
回顾性纳入 851 名被诊断为哮喘的学龄前儿童，以研究小气道功能参数的特征。采用曲线估计分析阐明大小气道功能障碍之间的相关性。采用 Spearman 相关和受试者工作特征（ROC）曲线评估小气道功能障碍（SAD）与 AHR 的关系。
在这项横断面队列研究中，SAD 的患病率为 19.5%（166/851）。小气道功能参数（FEF25-75%、FEF50%、FEF75%）与 FEV%（r=0.670、0.658、0.609，p<0.001）、FEV/FVC%（r=0.812、0.751、0.871，p<0.001）和 PEF%（r=0.626、0.635、0.530，p<0.01）呈强相关性。此外，小气道功能参数和大气道功能参数（FEV%、FEV/FVC%、PEF%）呈曲线相关，而不是线性相关（p<0.001）。FEF25-75%、FEF50%、FEF75%和 FEV%与 PC 呈正相关（r=0.282、0.291、0.251、0.224，p<0.001）。有趣的是，FEF25-75%和 FEF50%与 PC 的相关性系数高于 FEV%（0.282 与 0.224，p=0.031 和 0.291 与 0.224，p=0.014）。预测中重度 AHR 的 ROC 曲线分析显示，FEF25-75%、FEF50%、FEF75%和 FEF25-75%和 FEF75%的曲线下面积（AUC）分别为 0.796、0.783、0.738 和 0.802。与肺功能正常的儿童相比，SAD 患儿年龄稍大，更有可能有哮喘和气流阻塞家族史，且 FEV%和 FEV/FVC%较低，PEF%较低，AHR 更严重，PC 较低（均 p<0.05）。
小气道功能障碍与学龄前哮喘儿童的大气道功能损害、严重气流阻塞和 AHR 高度相关。小气道功能参数应应用于学龄前哮喘的管理。
