[CT imaging of COPD--importance of phenotyping (emphysema dominant and airway disorder dominant)].

We have been engaged in the analysis of the distribution of low attenuation area (LAA) representing emphysema, and the measurement of airway dimensions using CT images from the view point of phenotyping of COPD. (1) L AA% (area ratio of LAA to all lung area) did not correlate with reversibility to bronchodilators, whereas WA% (area ratio of bronchial wall to cross section of bronchus) positively correlated with reversibility. Thus, bronchodilators may be effective in proportional to the extent of airway disorders. (2) The incidence of Gc*1F(+) was significantly higher in patients with severe emphysema. These results indicate that the patients with Gc*1F(+) have rapid development of emphysema. (3) Polymorphism of MMP-9 (C -1562T) was associated with upper lung dominant emphysema in patients with COPD. (4) CT measurements of emphysema were greater in the patients with anorexia nervosa than in historical control subjects (p<0.001). Furthermore, there were significant correlations between the body mass index and the CT measures of emphysema. These data demonstrate that emphysema-like changes are present in the lungs of patients who are chronically malnourished.