Computed tomography (CT)-assessed bronchodilation induced by inhaled indacaterol and glycopyrronium/indacaterol in COPD.
Our previous studies suggested that the site of bronchodilation on CT might differ between inhaled β2 agonists and inhaled anticholinergics in COPD.



To assess and compare the bronchodilation effects of inhaled indacaterol and glycopyrronium/indacaterol by airway generation in large airways using CT.



CT scans at full inspiration and pulmonary function tests were done in 25 patients with moderate-severe COPD before and 4-5 weeks after daily inhalation of indacaterol and again another 4-5 weeks after inhalation of glycopyrronium/indacaterol. Airway inner luminal area (Ai) at the 3rd (segmental) to 6th generation of 8 selected bronchi, a total of 32 sites, in the right lung was analyzed on 3 occasions. Our proprietary software enables us to select the same airways and the same measurement sites for comparison, with simultaneous confirmation using two screens on the computer.



The overall increase of Ai (ΔAi, %) averaged at all 32 measurement sites induced by glycopyrronium/indacaterol had a significant correlation with FEV1 improvement (r = 0.7466, p < 0.0001). Both ΔAi, % with indacaterol and ΔAi, % with additional glycopyrronium were significant at the 3rd to 6th generations. Remarkable increases in ΔAi, % were found at the 5th and 6th generations in several subjects with indacaterol or additional glycopyrronium. There were no significant site-differences in the bronchodilation pattern caused by indacaterol and by glycopyrronium/indacaterol at any of the 3rd to 6th generations.



Additional bronchodilation with glycopyrronium was demonstrated by CT at the 3rd to 6th generations, with no site-specific differences in bronchodilation between indacaterol and glycopyrronium/indacaterol. This study was registered in the UMIN Clinical Trials Registry (UMIN-CTR) system (http://www.umin.ac.jp/. ID. UMIN000012043).
First Department of Medicine, Hokkaido University School of Medicine, Japan.
Kaoruko
K
Shimizu
Division of Respiratory Medicine, Department of Medicine, Shiga University of Medical Science, Japan.
Ruriko
R
Seto
First Department of Medicine, Hokkaido University School of Medicine, Japan.
Hironi
H
Makita
First Department of Medicine, Hokkaido University School of Medicine, Japan.
Masaru
M
Suzuki
First Department of Medicine, Hokkaido University School of Medicine, Japan.
Satoshi
S
Konno
Department of Biostatistics, Hokkaido University School of Medicine, Japan.
Yoichi M
YM
Ito
Division of Respiratory Medicine, Department of Medicine, Shiga University of Medical Science, Japan.
Rie
R
Kanda
Division of Respiratory Medicine, Department of Medicine, Shiga University of Medical Science, Japan; Health Administration Center, Shiga University of Medical Science, Japan.
Emiko
E
Ogawa
Division of Respiratory Medicine, Department of Medicine, Shiga University of Medical Science, Japan.
Yasutaka
Y
Nakano
First Department of Medicine, Hokkaido University School of Medicine, Japan. Electronic address: ma-nishi@med.hokudai.ac.jp.
Masaharu
M
Nishimura
D000280:Administration, Inhalation; D000318:Adrenergic beta-Agonists / Q000627:therapeutic use; D000368:Aged; D000369:Aged, 80 and over; D001980:Bronchi / Q000000981:diagnostic imaging* / Q000187:drug effects / Q000503:physiopathology; D001993:Bronchodilator Agents / Q000494:pharmacology; D004359:Drug Therapy, Combination / Q000379:methods; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006024:Glycopyrrolate / Q000008:administration & dosage* / Q000494:pharmacology; D006801:Humans; D007189:Indans / Q000008:administration & dosage* / Q000494:pharmacology; D007564:Japan / Q000453:epidemiology; D008168:Lung / Q000000981:diagnostic imaging* / Q000187:drug effects / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D018727:Muscarinic Antagonists / Q000627:therapeutic use; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000503:physiopathology; D015363:Quinolones / Q000008:administration & dosage* / Q000494:pharmacology; D012129:Respiratory Function Tests; D014057:Tomography, X-Ray Computed / Q000379:methods*
D000318:Adrenergic beta-Agonists; D001993:Bronchodilator Agents; D007189:Indans; D018727:Muscarinic Antagonists; D015363:Quinolones; C510790:indacaterol; D006024:Glycopyrrolate
Anticholinergics; Bronchodilation; Pulmonary function tests; Three-dimensional computed tomography; β2 agonists