D2.126 - Analysis of Clinical Characteristics and Airway Morphological Structure Parameters in Patients with Bronchial Asthma Combined with Bronchiectasis

Asthma comorbid with bronchiectasis is not uncommon, yet there are limited studies reporting on this condition. This study aims to compare the differences in demographic characteristics, fractional exhaled nitric oxide (FeNO), and pulmonary function between asthma patients with bronchiectasis and those with asthma alone, and to explore the differences in airway morphology between the two groups through three-dimensional quantitative CT scans.

This study enrolled 140 patients diagnosed with asthma comorbid with bronchiectasis and 144 gender- and age-matched inpatients with asthma alone. Based on eosinophil counts, patients were categorized into a non-eosinophilic asthma (NEA) group and an eosinophilic asthma (EA) group. Clinical data and chest CT/HRCT results were analyzed. Fully automated three-dimensional quantitative measurements of airway morphology were performed using FACT-Digital Lung TM software. 

In the NEA group, patients with asthma comorbid with bronchiectasis exhibited lower BMI, longer duration of asthma, a higher prevalence of corticosteroid therapy, and more severe impairment of pulmonary function compared to those with asthma alone. In addition, significant reductions were observed in FEV1, FEV1% predicted, FEV1/FVC, FEV1/VC max, PEF, MEF75, MEF50, MEF25, MMEF75/25, MVV, and DLCO. There were no statistically significant differences in EOS, EOS%, immunoglobulin E (IgE), and FeNO between the asthma-alone group and the comorbidity group. Differences in height, weight, and gender had an impact on airway morphological analysis. After adjusting for body surface area (BSA), statistically significant differences were observed in L/BSA, D/BSA, LA/BSA, WA/BSA, and LA%/BSA between patients with asthma complicated with bronchiectasis and those with asthma alone in the NEA group. In contrast, no statistically significant differences in the above indicators were found between the two subgroups in the EA group.

In the NEA group, patients with asthma comorbid with bronchiectasis had a lower BMI, a longer duration of asthma history, a higher prevalence of corticosteroid therapy, and more severe impairment of lung function. Additionally, airway remodeling was observed in the proximal airways, suggesting that this patient population has a unique clinical phenotype.