Airway wall thickness and pulmonary functions in patients with bronchial asthma: Assessment with high resolution computed tomography (HRCT) / 천식및알레르기

ABSTRACT

BACKGROUND: The presence of airway wall thickening and its relationship with pulmonary functions or airway hyperresponsiveness (AHR) have not yet been sufficiently clarified in bronchial asthma. OBJECTIVE: We investigated the relation of airway wall thickness to the pulmonary functions and AHR in patients with asthma. METHODS: After baseline measurement of pulmonary functions and PC20 in 24 patients, we measured airway wall thickness (T), internal diameter (d) using HRCT and calculated external diameter (D)[(D)=(d)+ 2x(T)]. We used the T/D ratio as a parameter for comparisons with pulmonary functions and PC20. RESULTS: We measured total 185 airways (upper;92, lower;93). The mean T/D ratio of small airways (diameteror=2mm;n=74) (0.324 +/- 0.028 vs 0.274 +/- 0.033, p<0.001). The mean T/D ratio of each subjects showed significant negative correlation with FEV1(% of predicted) in total (r=-0.407, p=0.048) and small airways (r=-0.468, p=0.024). PC20 showed a tendency of weak negative correlation with mean T/D ratio in small airways (r=-0.290, p=0.179). CONCLUSION: The thicker the airway wall is, the lower the FEV1 (% of predicted) in patients with bronchial asthma. Airway wall thickening occurred predominantly in the small airways.