Nadeem Syed Ahmed, Zhang Xinyu, Nagpal Prashant, Hoffman Eric A, Chan Kung-Sik, Comellas Alejandro P, Saha Punam K
Department of Radiology, University of Iowa, Iowa City, IA 52242, United States.
Department of Statistics and Actuarial Science, University of Iowa, Iowa City, IA 52242, United States.
Br J Radiol. 2025 Jan 1;98(1165):150-159. doi: 10.1093/bjr/tqae211.
We examine pathways of airway alteration due to wall thinning, narrowing, and obliteration in chronic obstructive pulmonary disease (COPD) using CT-derived airway metrics.
Ex-smokers (N = 649; age mean ± std: 69 ± 6 years; 52% male) from the COPDGene Iowa cohort (September 2013-July 2017) were studied. Total airway count (TAC), peripheral TAC beyond 7th generation (TACp), and airway wall thickness (WT) were computed from chest CT scans using previously validated automated methods. Causal relationships among demographic, smoking, spirometry, COPD severity, airway counts, WT, and scanner variables were analysed using causal inference techniques including direct acyclic graphs to assess multi-pathway alterations of airways in COPD.
TAC, TACp, and WT were significantly lower (P < .0001) in mild, moderate, and severe COPD compared to the preserved lung function group. TAC (TACp) losses attributed to narrowing and obliteration of small airways were 4.59%, 13.29%, and 32.58% (4.64%, 17.82%, and 45.51%) in mild, moderate, and severe COPD, while the losses attributed to wall thinning were 8.24%, 17.01%, and 22.95% (12.79%, 25.66%, and 33.95%) in respective groups.
Different pathways of airway alteration in COPD are observed using CT-derived automated airway metrics. Wall thinning is a dominant contributor to both TAC and TACp loss in mild and moderate COPD while narrowing and obliteration of small airways is dominant in severe COPD.
This automated CT-based study shows that wall thinning dominates airway alteration in mild and moderate COPD while narrowing and obliteration of small airways leads the alteration process in severe COPD.
我们使用CT衍生的气道指标，研究慢性阻塞性肺疾病（COPD）中由于气道壁变薄、狭窄和闭塞导致的气道改变途径。
对来自COPDGene爱荷华队列（2013年9月至2017年7月）的前吸烟者（N = 649；年龄均值±标准差：69±6岁；52%为男性）进行研究。使用先前验证的自动化方法，从胸部CT扫描中计算总气道计数（TAC）、第7代以外的外周TAC（TACp）和气道壁厚度（WT）。使用包括直接无环图在内的因果推断技术，分析人口统计学、吸烟、肺功能测定、COPD严重程度、气道计数、WT和扫描仪变量之间的因果关系，以评估COPD气道的多途径改变。
与肺功能正常组相比，轻度、中度和重度COPD患者的TAC、TACp和WT显著降低（P <.0001）。轻度、中度和重度COPD中，因小气道狭窄和闭塞导致的TAC（TACp）损失分别为4.59%、13.29%和32.58%（4.64%、17.82%和45.51%），而各相应组中因气道壁变薄导致的损失分别为8.24%、17.01%和22.95%（12.79%、25.66%和33.95%）。
使用CT衍生的自动化气道指标可观察到COPD气道改变的不同途径。在轻度和中度COPD中，气道壁变薄是导致TAC和TACp损失的主要因素，而在重度COPD中，小气道狭窄和闭塞起主导作用。
这项基于CT的自动化研究表明，在轻度和中度COPD中，气道壁变薄主导气道改变，而在重度COPD中，小气道狭窄和闭塞主导改变过程。
