Etiology and clinical characteristics of bronchiectasis in Taiwan: a multi-center cohort study

Abstract

Bronchiectasis is a chronic respiratory infectious disease with diverse causes and ethnic or geographic differences, but few large-scale studies on the etiology were investigated in Asia. This study aims to determine etiology and clinical features of bronchiectasis in Taiwan. This multi-center cohort study investigated non-CF bronchiectasis patients newly diagnosed from 2002/1/1 to 2016/12/31. The clinical data was retrieved from five medical centers across Taiwan. The index date was bronchiectasis firstly diagnosed. Known diseases that existed before the index date were regarded as etiologies of bronchiectasis. A total of 15,729 adult patients with bronchiectasis were included. Idiopathic (32%) was the most common cause, followed by post-pneumonia (24%). Other causes included post-tuberculosis (12%), chronic obstructive pulmonary disease (14%), asthma (10%), gastroesophageal reflux disease (2%) and rheumatic diseases (2%). Age, gender, lung function and commorbidities were significantly different between idiopathic and known etiologies. 8,487 patients had sputum culture at diagnosis. Pseudomonas aeruginosa (5.3%) was the most common bacteria, followed by non-tuberculosis mycobacteria(NTM) (3.6%), Haemo. influenzae (3.4%) and Kleb. pneumoniae (3.1%), but 6,155(72.1%) with negative sputum culture. NTM ranked first in post-TB patients. Post-TB and post-pneumonia bronchiectasis patients had a higher frequency of chronic lung infection than other groups (p Idiopathic, post-infectious and tuberculosis constituted major bronchiectasis etiologies in Taiwan. Clinical characteristics and sputum microbiology of patients between known etiologies and idiopathic bronchiectasis were different.