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

Received 22 June 2009; accepted 28 October 2009. published online 18 November 2009.

Summary

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 FEV1 more than 45% of the predicted value. The obstruction-dominant subtype had an emphysema index≤20% and FEV1≤45%, the mild-mixed subtype had an emphysema index≤20% and FEV1>45%, and the severe-mixed subtype had an emphysema index>20% and FEV1≤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 FEV1 increase and more marked dyspnea improvement than did the emphysema-dominant subgroup. The mixed-subtype patients (both subgroups) also showed significant improvement in FEV1 compared with the emphysema-dominant subgroup. Emphysema-dominant subtype patients showed no improvement in FEV1 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.

Keywords: COPD, Subtype, Inhaled long acting bronchodilator, Corticosteroid

a Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Bundang CHA Hospital, College of Medicine, CHA University, Seongnam, South Korea

b Department of Radiology, East-West Neo Medical Center, Kyunghee University, Seoul, South Korea

c Division of Pulmonology, Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, South Korea

d Department of Internal Medicine, Ilsan Paik Hospital, Inje University, Goyang, South Korea

e Department of Internal Medicine, College of Medicine, Kangwon National University, Chuncheon, South Korea

f Department of Internal Medicine, Ewha Womans University Mokdong Hospital, College of Medicine, Ewha Womans University, Seoul, South Korea

g Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Clinical Research Institute, Seoul National University Hospital, Lung Institute, Medical Research Center, Seoul National University College of Medicine, Seoul, South Korea

h Division of Respiratory and Critical Care Medicine, Department of Internal Medicine, College of Medicine, Korea University Anam Hospital, Seoul, South Korea

i Division of Pulmonary and Critical Care Medicine, Department of Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, South Korea

j Department of Internal Medicine, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul, South Korea

k Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, South Korea

l Department of Pulmonary and Critical Care Medicine, Ajou University School of Medicine, Suwon, South Korea

m Department of Radiology, and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea

n Department of Pulmonary and Critical Care Medicine, and Clinical Research Center for Chronic Obstructive Airway Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 388-1 Pungnap-dong, Sonpa-gu, Seoul 138-736, South Korea

Corresponding author. Tel.: +82 2 3010 3136; fax: +82 2 3010 6968.

Corresponding author. Tel.: +82 2 3010 3140; fax: +82 2 3010 6968.

☆ Both authors contributed equally to this work with senior responsibilities.

PII: S0954-6111(09)00359-X

doi:10.1016/j.rmed.2009.10.024

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