Sangyeub Lee

Responses to inhaled long-acting beta-agonist and corticosteroid according to COPD subtype☆

RATIONALE Chronic obstructive pulmonary disease (COPD) is a complex and heterogeneous disorder in which a number of different pathological processes lead to recognition of patient subgroups that may have individual characteristics and distinct responses to treatment. OBJECTIVES We tested the hypothesis that responses of lung function to 3 months of combined inhalation of long-acting beta-agonist and corticosteroid might differ among patients with various COPD subtypes. METHODS We classified 165 COPD patients into four subtypes according to the severity of emphysema and airflow obstruction: emphysema-dominant, obstruction-dominant, mild-mixed, and severe-mixed. The emphysema-dominant subtype was defined by an emphysema index on computed tomography of more than 20% and FEV(1) more than 45% of the predicted value. The obstruction-dominant subtype had an emphysema index < or = 20% and FEV(1) < or = 45%, the mild-mixed subtype had an emphysema index < or = 20% and FEV(1) > 45%, and the severe-mixed subtype had an emphysema index > 20% and FEV(1) < or = 45%. Patients were recruited prospectively and treated with 3 months of combined inhalation of long-acting beta-agonist and corticosteroid. RESULTS After 3 months of combined inhalation of long-acting beta-agonist and corticosteroid, obstruction-dominant subtype patients showed a greater FEV(1) increase and more marked dyspnea improvement than did the emphysema-dominant subgroup. The mixed-subtype patients (both subgroups) also showed significant improvement in FEV(1) compared with the emphysema-dominant subgroup. Emphysema-dominant subtype patients showed no improvement in FEV(1) or dyspnea after the 3-month treatment period. CONCLUSION The responses to 3 months of combined inhalation of long-acting beta-agonist and corticosteroid differed according to COPD subtype.

Association between CRHR1 polymorphism and improved lung function in response to inhaled corticosteroid in patients with COPD

Background and objective:  Inhaled corticosteroids are used to treat COPD and asthma. An association between sequence variants in the corticotrophin‐releasing hormone receptor 1 (CRHR1) gene and improved lung function in asthmatics treated with inhaled corticosteroids was reported recently. This study investigated the association between the change in lung function in response to inhaled corticosteroids and single‐nucleotide CRHR1 polymorphisms in patients with COPD.

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

Background:  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; FEV1), 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.

Predictors of Pulmonary Function Response to Treatment with Salmeterol/fluticasone in Patients with Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease and responses to therapies are highly variable. The aim of this study was to identify the predictors of pulmonary function response to 3 months of treatment with salmeterol/fluticasone in patients with COPD. A total of 127 patients with stable COPD from the Korean Obstructive Lung Disease (KOLD) Cohort, which were prospectively recruited from June 2005 to September 2009, were analyzed retrospectively. The prediction models for the FEV1, FVC and IC/TLC changes after 3 months of treatment with salmeterol/fluticasone were constructed by using multiple, stepwise, linear regression analysis. The prediction model for the FEV1 change after 3 months of treatment included wheezing history, pre-bronchodilator FEV1, post-bronchodilator FEV1 change and emphysema extent on CT (R = 0.578). The prediction models for the FVC change after 3 months of treatment included pre-bronchodilator FVC, post-bronchodilator FVC change (R = 0.533), and those of IC/ TLC change after 3 months of treatment did pre-bronchodilator IC/TLC and post-bronchodilator FEV1 change (R = 0.401). Wheezing history, pre-bronchodilator pulmonary function, bronchodilator responsiveness, and emphysema extent may be used for predicting the pulmonary function response to 3 months of treatment with salmeterol/fluticasone in patients with COPD.

Comparison of Clinico-Physiologic and CT Imaging Risk Factors for COPD Exacerbation

To date, clinico-physiologic indices have not been compared with quantitative CT imaging indices in determining the risk of chronic obstructive pulmonary disease (COPD) exacerbation. We therefore compared clinico-physiologic and CT imaging indices as risk factors for COPD exacerbation in patients with COPD. We retrospectively analyzed 260 COPD patients from pulmonary clinics at 11 hospitals in Korea from June 2005 to November 2009 and followed-up for at least one year. At the time of enrollment, none of these patients had COPD exacerbations for at least 2 months. All underwent clinico-physiologic and radiological evaluation for risk factors of COPD exacerbation. After 1 yr, 106 of the 260 patients had at least one exacerbation of COPD. Multiple logistic regression analysis showed that old age, high Charlson Index, and low FEV1 were significant in a clinico-physiologic model, with C-statistics of 0.69, and that increased age and emphysema index were significant in a radiologic model, with C-statistics of 0.64. The difference between the two models was statistically significant (P = 0.04 by bootstrap analysis). Combinations of clinico-physiologic risk factors may be better than those of imaging risk factors in predicting COPD exacerbation.