Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, New York University School of Medicine, New York, NY 10016, USA.
Department of Population Health, New York University School of Medicine, New York, NY 10016, USA.
Int J Environ Res Public Health. 2019 Apr 20;16(8):1421. doi: 10.3390/ijerph16081421.
The evolution of lung function, including assessment of small airways, was assessed in individuals enrolled in the World Trade Center Environmental Health Center (WTC-EHC). We hypothesized that a bronchodilator response at initial evaluation shown by spirometry or in small airways, as measured by forced oscillation technique (FOT), would be associated with improvement in large and small airway function over time. Standardized longitudinal assessment included pre and post bronchodilator (BD) spirometry (forced vital capacity, FVC; forced expiratory volume in 1 second, FEV) and FOT (resistance at 5 Hz, R; resistance at 5 minus 20 Hz, R). Longitudinal changes were assessed using linear mixed-effects modelling with adjustment for potential confounders (median follow-up 2.86 years; 95% measurements within 4.9 years). Data demonstrated: (1) parallel improvement in airflow and volume measured by spirometry and small airway function (R and R) measured by FOT; (2) the magnitude of longitudinal improvement was tightly linked to the initial BD response; and (3) longitudinal values for small airway function on FOT were similar to residual abnormality observed post BD at initial visit. These findings suggest presence of reversible and irreversible components of small airway injury that are identifiable at initial presentation. These results have implications for treatment of isolated small airway abnormalities that can be identified by non-invasive effort independent FOT particularly in symptomatic individuals with normal spirometry indices. This study underscores the need to study small airway function to understand physiologic changes over time following environmental and occupational lung injury.
肺功能的演变，包括小气道的评估，在世界贸易中心环境健康中心（WTC-EHC）登记的个体中进行了评估。我们假设初始评估时通过肺活量计或强制振荡技术（FOT）测量的小气道显示出支气管扩张剂反应，与随时间推移大、小气道功能的改善有关。标准化的纵向评估包括初始支气管扩张剂（BD）后肺量计（用力肺活量，FVC；第一秒用力呼气量，FEV）和 FOT（5 Hz 时的阻力，R；5 减去 20 Hz 时的阻力，R）的预和后测量。使用线性混合效应模型进行纵向变化评估，并对潜在混杂因素进行调整（中位随访 2.86 年；95%的测量值在 4.9 年内）。数据表明：（1）通过肺活量计测量的气流和容积以及通过 FOT 测量的小气道功能（R 和 R）的平行改善；（2）纵向改善的幅度与初始 BD 反应密切相关；（3）FOT 上小气道功能的纵向值与初始就诊时 BD 后观察到的残留异常相似。这些发现表明，在初始表现时，小气道损伤存在可逆转和不可逆转的成分。这些结果对治疗孤立的小气道异常具有意义，这些异常可以通过非侵入性的、独立于努力的 FOT 来识别，特别是在肺功能指数正常的有症状个体中。本研究强调需要研究小气道功能，以了解环境和职业性肺损伤后随时间的生理变化。
