Journal of Asthma and Allergy (Apr 2024)
Usefulness of Computed Tomography for Evaluating the Effects of Bronchial Thermoplasty in Japanese Patients with Severe Asthma
Abstract
Sumiko Abe,1 Mina Yasuda,1,2 Kazunori Tobino,1,2 Sonoko Harada,1,3 Hitoshi Sasano,1 Yuki Tanabe,1 Yuuki Sandhu,1 Tomohito Takeshige,1 Kei Matsuno,1 Tetsuhiko Asao,1 Takuto Sueyasu,2 Saori Nishizawa,2 Kohei Yoshimine,2 Yuki Ko,2 Yuki Yoshimatsu,2 Kosuke Tsuruno,2 Hiromi Ide,2 Haruhi Takagi,1 Jun Ito,1 Tetsutaro Nagaoka,1 Norihiro Harada,1,3,4 Kazuhisa Takahashi1,4 1Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan; 2Department of Respiratory Medicine, Iizuka Hospital, Fukuoka, Japan; 3Atopy (Allergy) Research Center, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan; 4Research Institute for Diseases of Old Age, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, JapanCorrespondence: Norihiro Harada, Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan, Tel +81-3-5802-1063, Fax +81-3-5802-1617, Email [email protected]: Bronchial thermoplasty (BT) improves clinical outcomes and quality of life for patients with severe asthma and has shown sustained reductions in airway narrowing and air trapping in previous CT studies. However, there is a lack of a comprehensive analysis, including CT evaluation, of clinical outcomes in Japanese patients who have undergone BT for severe asthma. This study aimed to evaluate the impact of BT in Japanese asthma patients, with a focus on the CT metric “WA at Pi10” to assess airway disease.Methods: Twelve patients with severe persistent asthma who underwent BT were assessed using ACQ6, AQLQ, pulmonary function tests, FeNO measurement, blood sampling, and chest CT before BT and one year after the third procedure for the upper lobes.Results: The median age of the patient was 62.0 years, 7/12 (58.3%) were male, 4/12 (33.3%) used regular oral corticosteroids, and 8/12 (66.7%) received biologics. Median FEV1% was 73.6%, and median peripheral eosinophil count was 163.8/μL. After one year of BT, ACQ6 scores improved from 2.4 to 0.8 points (p = 0.007), and AQLQ scores improved from 4.3 to 5.8 points (p < 0.001). Significant improvements were also observed in asthma exacerbations, unscheduled visits due to exacerbations, FeNO, and √WA at Pi10 (p < 0.05). The baseline mucus score on the CT findings was negatively correlated with FEV1 (r = − 0.688, p = 0.013) and with the maximum mid-expiratory flow rate (r = − 0.631, p = 0.028), and positively correlated with the peripheral blood eosinophil count (r = − 0.719, p = 0.008). Changes in √WA at Pi10 after one year were positively correlated with changes in the mucus score (r = 0.742, p = 0.007).Conclusion: This study has limitations, including its single-arm observational design and the small sample size. However, BT led to a symptomatic improvement in patients with severe asthma. The validated “√WA at Pi10” metric on CT effectively evaluated the therapeutic response in Japanese asthma patients after BT.Keywords: asthma, bronchial thermoplasty, chest computed tomography, asthma control questionnaire, √WA at Pi10