Role Of Noninvasive Methods For Assessing Stable Non-Cystic Fibrosis Bronchiectasis

Background: Bronchiectasis is characterized by the abnormal dilation of lung airways. Only some patients with bronchiectasis may clinically benefit from the treatment recommended in the guidelines of the European Respiratory Society. The value of noninvasive methods for assessing the clinical phenotypes of stable-state non-cystic fibrosis (non-CF) bronchiectasis for treatable characteristics has not been adequately studied.Methods: Eighty-nine patients with stable non-CF bronchiectasis were retrospectively enrolled. Patient characteristics, fractional exhaled nitric oxide (FeNO) values, and the results of blood tests for inflammatory markers, pulmonary function test, high-resolution computed tomography (HRCT), and bronchial hyper-responsiveness test or bronchodilator reversibility test were obtained. These data were used to assess the factors associated with the clinical phenotype of bronchiectasis.Results: The majority of the patients were female (60.67%) and have an average age of 59.08±15.09 years old. The predicted percentages of forced expiratory volume in 1 s (FEV1) and the ratio of FEV1 and forced vital capacity were 56.17%±23.16% and 65.58%±15.26%, respectively. Eighteen (20.22%) of the patients with bronchiectasis had emphysema. The presence of emphysema in bronchiectasis was associated with a high airflow obstruction level. Seventeen (10.10%) of the patients with bronchiectasis had asthma. FeNO was significantly higher in the group of patients with bronchiectasis and asthma than in the other two groups (p < 0.01). The erythrocyte sedimentation rate (ESR) of the bronchiectasis alone group was higher than those of the other two groups. Significant negative correlations were found between ERS and FeNO levels (p = 0.02, r = −0.338), between HRCT score and FeNO levels (p = 0.04, r = −0.229), and between FEV1 (% predicted) and HRCT scores (p = 0.0007, r = −0.3629). A significant positive correlation was found between ERS and HRCT scores (p = 0.0001, r = 6326).Conclusion: A remarkable proportion of patients with bronchiectasis have emphysema or asthma. Biomarkers, such as FeNO, and conventional lung function tests should be routinely used for phenotyping bronchiectasis for potential targeted therapy. ESR can be used as a biomarker to reflect the level of systemic inflammation and the severity of bronchiectasis. These approaches will provide a better understanding of patients with bronchiectasis and their clinical phenotypes and lead to a more individualized and effective therapy.