Evaluation of Airway Wall Thickness Via High-Resolution Computed Tomography in Mild Intermittent Asthma

Abstract

This study aims to evaluate bronchial thickness via thorax high-resolution computed tomography (HRCT) in subjects with mild intermittent asthma in comparison with healthy control subjects. A total of 37 out-patients (mean ± SD age = 36.7 years (9.7 years); 54.8% males) with mild intermittent asthma and 13 healthy control subjects (mean ± SD age = 25.0 years (2.9 years); 61.5% males) were included in this case control study. Data on demographics, pulmonary function test results, and segmental and subsegmental thorax HRCT results were recorded. The ratio of bronchial wall thickness to bronchial lumen diameter (T/D) and bronchial wall area percentage (WA%) were calculated for all cases. Subject and control groups were similar in terms of pulmonary function test results, and total and subsegmental T/D values. Mean ± SD subsegmental WA% values at the level of inferior pulmonary vein (55.6% [16.8%] vs. 41.7% [7.4%], P = .047) and 2 cm above the diaphragm (49.8% [15.8%] vs. 38.6% [10.4%], P = .046) were significantly higher in subjects than control subjects. No significant correlation of overall and subsegmental T/D and WA% values to age in both groups, and to asthma duration in subjects. Our findings revealed an increase in bronchial wall thickness in peripheral airways in subjects with mild intermittent asthma regardless of the duration of asthma. This may indicate a need to also administer anti-inflammatory or bronchodilator therapy, which is effective in peripheral airways during the early period of the disease.