Structural and Functional Features on Quantitative Chest Computed Tomography in the Korean Asian versus the White American Healthy Non-Smokers

Korean J Radiol. 2019 Jul;20(7):1236-1245. doi: 10.3348/kjr.2019.0083.

Abstract

Objective: Considering the different prevalence rates of diseases such as asthma and chronic obstructive pulmonary disease in Asians relative to other races, Koreans may have unique airway structure and lung function. This study aimed to investigate unique features of airway structure and lung function based on quantitative computed tomography (QCT)-imaging metrics in the Korean Asian population (Koreans) as compared with the White American population (Whites).

Materials and methods: QCT data of healthy non-smokers (223 Koreans vs. 70 Whites) were collected, including QCT structural variables of wall thickness (WT) and hydraulic diameter (Dh) and functional variables of air volume, total air volume change in the lung (ΔVair), percent emphysema-like lung (Emph%), and percent functional small airway disease-like lung (fSAD%). Mann-Whitney U tests were performed to compare the two groups.

Results: As compared with Whites, Koreans had smaller volume at inspiration, ΔVair between inspiration and expiration (p < 0.001), and Emph% at inspiration (p < 0.001). Especially, Korean females had a decrease of ΔVair in the lower lobes (p < 0.001), associated with fSAD% at the lower lobes (p < 0.05). In addition, Koreans had smaller Dh and WT of the trachea (both, p < 0.05), correlated with the forced expiratory volume in 1 second (R = 0.49, 0.39; all p < 0.001) and forced vital capacity (R = 0.55, 0.45; all p < 0.001).

Conclusion: Koreans had unique features of airway structure and lung function as compared with Whites, and the difference was clearer in female individuals. Discriminating structural and functional features between Koreans and Whites enables exploration of inter-racial differences of pulmonary disease in terms of severity, distribution, and phenotype.

Keywords: Airway wall thickness; Hydraulic luminal diameter; Image registration; Percent emphysema-like lung; Percent functional small airway disease-like lung.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Asian People
  • Asthma / diagnostic imaging
  • Asthma / physiopathology*
  • Female
  • Forced Expiratory Volume
  • Humans
  • Lung / diagnostic imaging
  • Lung / physiopathology
  • Lung / ultrastructure*
  • Male
  • Middle Aged
  • Non-Smokers
  • Prevalence
  • Pulmonary Disease, Chronic Obstructive / diagnostic imaging
  • Pulmonary Disease, Chronic Obstructive / physiopathology*
  • Pulmonary Emphysema / diagnostic imaging
  • Pulmonary Emphysema / physiopathology*
  • Republic of Korea
  • Respiratory Function Tests
  • Retrospective Studies
  • Tomography, X-Ray Computed / methods*
  • United States
  • White People