Department of Respiratory Medicine, Concord Repatriation General Hospital, Concord, New South Wales, Australia.
Airway Physiology and Imaging Group and Woolcock Emphysema Centre, Woolcock Institute of Medical Research, Glebe, New South Wales, Australia.
Respirology. 2021 Jun;26(6):566-573. doi: 10.1111/resp.14053. Epub 2021 Apr 1.
Asthma guidelines emphasize the importance of assessing lung function and symptoms. The forced oscillation technique (FOT) and its longitudinal relationship with spirometry and symptoms are unresolved. We examined concordance between longitudinal spirometry, FOT and symptom control, and determined FOT limits of agreement in stable asthma.
Over a 3-year period, adults with asthma attending a tertiary clinic completed the asthma control test (ACT), fraction of exhaled nitric oxide (FeNO), FOT and spirometry. Analysis included between-visit concordance for significant change using Cohen's kappa (κ) and stable asthma FOT limits of agreement.
Data (n = 186) from 855 visits (mean ± SD 4.6 ± 3.0 visits), 114 ± 95 days apart, were analysed. Between-visit concordance was moderate between reactance at 5 Hz (X5) and forced expiratory volume in 1 s (FEV ) (κ = 0.34, p = 0.001), and weak between ACT and FEV (κ = 0.18, p = 0.001). Change in FeNO did not correlate with lung function or ACT (κ < 0.05, p > 0.1). Stable asthma between visits (n = 75; 132 visits) had reduced lung function variability, but comparable concordance to the entire cohort. Limits of agreement for FEV (0.42 L), resistance at 5 Hz (2.06 cm H O s L ) and X5 (2.75 cm H O s L ) in stable asthma were at least twofold greater than published values in health.
In adults with asthma, there is moderate concordance between longitudinal change in FOT and spirometry. Both tests relate poorly to changes in asthma control, highlighting the need for multi-modal assessment in asthma rather than symptoms alone. The derivation of longitudinal FOT limits of agreement will assist in its clinical interpretation.
哮喘指南强调评估肺功能和症状的重要性。振荡技术（FOT）及其与肺活量和症状的纵向关系尚未解决。我们检查了纵向肺活量、FOT 和症状控制之间的一致性，并确定了稳定哮喘中 FOT 的一致性界限。
在 3 年期间，在一家三级诊所就诊的哮喘患者完成了哮喘控制测试（ACT）、呼气一氧化氮分数（FeNO）、FOT 和肺活量。分析包括使用 Cohen's kappa（κ）检查显著变化的访间一致性，以及稳定哮喘 FOT 的一致性界限。
分析了来自 855 次就诊（平均±标准差 4.6±3.0 次就诊）的数据，两次就诊之间间隔 114±95 天。电抗在 5Hz（X5）和 1 秒用力呼气量（FEV ）之间的访间一致性为中度（κ=0.34，p=0.001），ACT 和 FEV 之间的一致性为弱（κ=0.18，p=0.001）。FeNO 的变化与肺功能或 ACT 无关（κ<0.05，p>0.1）。两次就诊之间的稳定哮喘（n=75；132 次就诊）的肺功能变异性降低，但与整个队列的一致性相当。稳定哮喘中 FEV（0.42L）、5Hz 阻力（2.06cm H O s L ）和 X5（2.75cm H O s L ）的一致性界限至少是健康人群中公布值的两倍。
在哮喘患者中，FOT 和肺活量的纵向变化之间存在中度一致性。这两种测试与哮喘控制的变化相关性较差，这强调了在哮喘中需要进行多模态评估，而不仅仅是症状评估。FOT 纵向一致性界限的推导将有助于其临床解释。
