Ho Jung Jeong, Hyun Lee, Keumhee C Carriere, Jung Hoon Kim, Jin-Hyung Han, Beomsu Shin, Byeong-Ho Jeong, Won-Jung Koh, O Jung Kwon, Hye Yun Park

The association between positive bronchodilator response (BDR) at baseline and the effect of long-term bronchodilator therapy has not been well elucidated in patients with bronchiectasis. The aims of our study were to explore the association between positive BDR at baseline and lung-function improvement following long-term (3-12 months) bronchodilator therapy in bronchiectasis patients with airflow limitation. The medical records of 166 patients with clinically stable bronchiectasis who underwent baseline pre- and postbronchodilator spirometry and repeated spirometry after 3-12 months of bronchodilator therapy were retrospectively reviewed. For analysis, patients were divided into two groups, responders and poor responders, based on achievement of at least 12% and 200 mL in forced expiratory volume in 1 second (FEV1) following bronchodilator therapy from baseline FEV1. A total of 57 patients (34.3%) were responders. These patients were more likely to have positive BDR at baseline than poor responders (38.6% [22 of 57] vs 18.3% [20 of 109], P=0.004). This association persisted after adjustment for other confounding factors (adjusted odds ratio 2.298, P=0.034). However, we found FEV1 improved significantly following long-term bronchodilator therapy, even in patients without positive BDR at baseline (change in FEV1 130 mL, interquartile range -10 to 250 mL; P<0.001). Positive BDR at baseline was independently associated with responsiveness to long-term bronchodilator therapy in bronchiectasis patients with airflow limitation. However, FEV1 improvement was also evident in bronchiectasis patients without positive BDR at baseline, suggesting that these patients can benefit from long-term bronchodilator therapy.