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


OBJECTIVE
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.


CONCLUSIONS
The responses to 3 months of combined inhalation of long-acting beta-agonist and corticosteroid differed according to COPD subtype.
Lee
Ji-Hyun
JH
Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Bundang CHA Hospital, College of Medicine, CHA University, Seongnam, South Korea.
Lee
Young Kyung
YK
Kim
Eun-Kyung
EK
Kim
Tae-Hyung
TH
Huh
Jin Won
JW
Kim
Woo Jin
WJ
Lee
Jin Hwa
JH
Lee
Sang-Min
SM
Lee
Sangyeub
S
Lim
Seong Yong
SY
Shin
Tae Rim
TR
Yoon
Ho Il
HI
Sheen
Seung Soo
SS
Kim
Namkug
N
Seo
Joon Beom
JB
Oh
Yeon-Mok
YM
Lee
Sang Do
SD
D000280:Administration, Inhalation; D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000368:Aged; D000704:Analysis of Variance; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D004334:Drug Administration Schedule; D004417:Dyspnea / Q000145:classification / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects / Q000502:physiology; D006801:Humans; D007723:Korea; D008297:Male; D010349:Patient Compliance; D029424:Pulmonary Disease, Chronic Obstructive / Q000145:classification / Q000188:drug therapy* / Q000503:physiopathology; D011656:Pulmonary Emphysema / Q000145:classification / Q000188:drug therapy* / Q000503:physiopathology; D018343:Receptors, Adrenergic, beta-2 / Q000627:therapeutic use*; D012720:Severity of Illness Index; D013147:Spirometry; D016896:Treatment Outcome
D000305:Adrenal Cortex Hormones; D001993:Bronchodilator Agents; D018343:Receptors, Adrenergic, beta-2