Response patterns to bronchodilator and quantitative computed tomography in chronic obstructive pulmonary disease

Department of Pulmonary and Critical Care Medicine, Asthma Center and Clinical Research Center for Chronic Obstructive Airway Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Clinical Physiology and Functional Imaging (Impact Factor: 1.44). 01/2012; 32(1):12-8. DOI: 10.1111/j.1475-097X.2011.01046.x
Source: PubMed


Patients with chronic obstructive pulmonary disease (COPD) show different spirometric response patterns to bronchodilator, such that some patients show improvement principally in expiratory flow (forced expiratory volume in 1 s; FEV(1)), whereas others respond by improvement of lung volume (forced vital capacity; FVC). The mechanisms of these different response patterns to bronchodilator remain unclear. We investigated the associations between bronchodilator responsiveness and quantitative computed tomography (CT) indices in patients with COPD.
Data on a total of 101 patients with stable COPD were retrospectively analysed. Volume and flow responses to bronchodilator were assessed by FVC and FEV(1) changes before and after inhalation of salbutamol (400 μg). Volumetric CT was performed to quantify emphysema, air trapping and large airway thickness. Emphysema was assessed by the volume fraction of the lung under -950 Hounsfield units (HU; V(950)) at full inspiration and air trapping by the ratio of mean lung density (MLD) at full expiration and inspiration. Airway wall thickness and wall area percentage (WA%; defined as wall area/[wall area + lumen area] × 100), were measured near the origin of right apical and left apico-posterior bronchus.
Among quantitative CT indices, the CT emphysema index (V(950 insp)) showed a significant negative correlation with postbronchodilator FEV(1) change (R = -0·213, P = 0·004), and the CT air-trapping index correlated positively with postbronchodilator FVC change(R = 0·286, P≤0·001). Multiple linear regression analysis showed that CT emphysema index had independent association with postbronchodilator FEV(1) change and CT air-trapping index with postbronchodilator FVC change.
The degrees of emphysema and air trapping may contribute to the different response patterns to bronchodilator in patients with COPD.

Download full-text


Available from: Seung Soo Sheen, Apr 07, 2014
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Chronic obstructive pulmonary disease (COPD) is a spectrum of various syndromes that share airflow limitation but differ in many respects. Although airflow limitation is a defining element of COPD, forced expiratory volume in 1 s (FEV1) alone is not sufficient to explain the heterogeneity of COPD. Phenotypic characterization of clinically relevant subgroups of COPD will increase our understanding of COPD. Furthermore, a greater understanding of the complex interrelationships between the phenotypes and their environmental, genetic, molecular, and cellular basis may be achieved with comprehensive and integrated method (systems biology and network medicine). Incorporation of information obtained from these analyses into our clinical practice would allow clinicians to treat individual patients with so-called Personalized, Predictive, Preventive, and Participatory (P4) medicine. By understanding COPD heterogeneity, it may be possible in the future to detect the disease earlier and to target treatment to reduce mortality and modify the course of the disease.
    Full-text · Article · Sep 2012
  • [Show abstract] [Hide abstract]
    ABSTRACT: Multicentre study. To define the clinical characteristics of patients with tuberculosis (TB) destroyed lung due to past TB. We reviewed patients with TB-destroyed lung between May 2005 and June 2011. A total of 595 patients from 21 hospitals were enrolled. The mean age was 65.63 ± 0.47 (mean ± standard error); 60.5% were male. The mean number of lobes involved was 2.59 ± 0.05. Pleural thickening was observed in 54.1% of the patients. Mean forced vital capacity (FVC), forced expiratory volume in 1 s (FEV(1)), FEV(1)/FVC, bronchodilator response and number of exacerbations per year were respectively 2.06 ± 0.03 l (61.26% ± 0.79), 1.16 ± 0.02 l (49.05% ± 0.84), 58.03% ± 0.70, 5.70% ± 0.34, and 0.40 ± 0.04. The number of lobes involved was significantly correlated with FVC and FEV(1), and with the number of exacerbations per year. Use of long-acting muscarinic antagonists or long-acting beta-2 agonists plus inhaled corticosteroids resulted in bronchodilatory effects. Multivariable regression analysis showed that age, initial FEV(1) (%) and number of exacerbations during follow-up were independent factors affecting change in FEV(1). Decreased lung function with exacerbation, and progressive decline of FEV(1) were observed in patients with TB-destroyed lung.
    No preview · Article · Jan 2013 · The International Journal of Tuberculosis and Lung Disease
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: In patients with chronic obstructive pulmonary disease (COPD), multidetector-row computed tomography (MDCT) showed that tiotropium dilated the inner diameters in airways from the third to the sixth generation of the bronchi. Here we aimed to evaluate the morphological effect by adding a budesonide/formoterol combination to tiotropium in COPD patients using three-dimensional MDCT. Methods: Pulmonary function tests, St. George's Respiratory Questionnaire (SGRQ) and MDCT imaging studies were performed at the beginning and after budesonide/formoterol combination treatment for 12 weeks in 14 patients with COPD. Results: The median age was 73.5 years and the mean forced expiratory volume in 1 s (FEV1) as a percentage of the predicted value was 57.2 ± 18.3%. The luminal area in the fifth generation bronchi and the emphysema volume/CT-derived total lung volume were significantly correlated with FEV1 at baseline (r = 0.682, p < 0.02 and r = -0.868, p < 0.001, respectively). The average luminal area and wall area percentage in the third, fourth and fifth generations were correlated with the SGRQ total score. Budesonide/formoterol induced insignificant pulmonary function changes and significant symptoms improvement. CT images showed an increased inner luminal area and decreased wall area after budesonide/formoterol treatment. Average luminal area was significantly increased from 24.3 ± 9.7 to 26.0 ± 9.9 mm(2) in the third generation, 13.0 ± 6.5 to 14.7 ± 7.3 mm(2) in the fourth generation, 8.0 ± 4.8 to 9.4 ± 4.9 mm(2) in the fifth generation and 5.6 ± 2.7 to 6.7 ± 3.6 mm(2) in the sixth generation (p < 0.01). The average increase of the third generation luminal area was correlated with the FEV1 increase (r = 0.632, p < 0.03). The wall area percentage significantly decreased from 51.5 ± 9.2 to 49.1 ± 9.7 in the third generation, 56.1 ± 9.7 to 53.0 ± 11.1 in the fourth generation, and 62.3 ± 9.9 to 57.6 ± 9.8 in the fifth generation (p < 0.05). Emphysema volume/CT-derived total lung volume was unchanged with treatment. Conclusion: MDCT demonstrated budesonide/formoterol induced bronchodilation in the non-small airway. CT imaging can evaluate drug therapeutic effect and may provide additional insights into pharmacotherapy for COPD.
    No preview · Article · Jan 2013 · Pulmonary Pharmacology & Therapeutics
Show more