Prevalence and clinical implications of bronchiectasis in patients with overlapping asthma and chronic rhinosinusitis: a single-center prospective study

BACKGROUND: As a typical “united airway” disease, asthma-chronic rhinosinusitis (CRS) overlap has recently drawn more attention. Bronchiectasis is a heterogeneous disease related to a variety of diseases. Whether bronchiectasis exists and correlates with asthma-CRS patients has not been fully elucidated. The purpose of the study was to explore the presence and characteristics of bronchiectasis in patients with overlapping asthma and CRS. METHODS: This report describes a prospective study with consecutive asthma-CRS patients. The diagnosis and severity of bronchiectasis were obtained by thorax high-resolution computed tomography (HRCT), the Smith radiology scale and the Bhalla scoring system. CRS severity was evaluated by paranasal sinus CT and the Lund-Mackay (LM) scoring system. The correlations between bronchiectasis and clinical data, fraction of exhaled nitric oxide, peripheral blood eosinophil counts and lung function were analyzed. RESULTS: Seventy-two (40.91%) of 176 asthma-CRS patients were diagnosed with bronchiectasis. Asthma-CRS patients with overlapping bronchiectasis had a higher incidence rate of nasal polyps (NPs) (P = 0.004), higher LM scores (P = 0.044), higher proportion of ≥ 1 severe exacerbation of asthma in the last 12 months (P = 0.003), lower postbronchodilator forced expiratory volume in one second (FEV(1)) % predicted (P = 0.006), and elevated peripheral blood eosinophil counts (P = 0.022). Smith and Bhalla scores were shown to correlate positively with NPs and negatively with FEV(1)% predicted and body mass index. Cutoff values of FEV(1)% predicted ≤ 71.40%, peripheral blood eosinophil counts > 0.60 × 10(9)/L, presence of NPs, and ≥ 1 severe exacerbation of asthma in the last 12 months were shown to differentiate bronchiectasis in asthma-CRS patients. CONCLUSIONS: Bronchiectasis commonly overlaps in asthma-CRS patients. The coexistence of bronchiectasis predicts a more severe disease subset in terms of asthma and CRS. We suggest that asthma-CRS patients with NPs, severe airflow obstruction, eosinophilic inflammation, and poor asthma control should receive HRCT for the early diagnosis of bronchiectasis.