Assessment of airway remodeling by quantitative computed tomography at various degrees of asthma severity defined according to the Global Initiative for Asthma report: a single-center study.

Abstract

In asthma, airway remodeling is defined as structural changes of the airways. The association between remodeling and asthma severity is still unclear, and there are limited data on the intensity of airway remodeling in various stages of the disease as defined in the Global Initiative for Asthma (GINA) asthma severity classification. Computed tomography (CT) and postprocessing applications are effective tools to assess the intensity of airway remodeling. The aim of this study was to assess the severity of morphometric abnormalities of the respiratory tract in patients with various degrees of asthma severity according to the GINA guidelines. The study included 70 patients with asthma and 29 healthy controls matched for age, sex, and body mass index. Patients were examined with a 128 multislice CT scanner at full inspiration. The measurements were made from the third to the ninth generations of bronchi. Bronchial parameters were compared between patients with severe and nonsevere asthma and healthy controls. We found no differences in the thickness of the bronchial wall, percentage of the wall area, inner and outer bronchial diameters, and the size of the bronchial lumen between severe and nonsevere asthma groups. Significant differences were noted in the thickness of the bronchial wall and the percentage of the wall area between the severe asthma group and the control group (P <0.017) as well as between the nonsevere asthma group and controls (P <0.017). Our findings indicated similar values of CT morphological measures of airway remodeling in all asthma severity groups as defined by the GINA guidelines.