TY - JOUR
T1 - Effects of inhaled steroids on methacholine-induced bronchoconstriction and gas trapping in mild asthma
AU - Corsico, A.
AU - Pellegrino, R.
AU - Zoia, M. C.
AU - Barbano, L.
AU - Brusasco, V.
AU - Cerveri, I.
PY - 2000
Y1 - 2000
N2 - According to a recent hypothesis, airway smooth muscle regulates airway calibre mostly at high lung volume, whereas the mucosa and adventitia dimensions dominate at low lung volumes. It was thought that if inhaled steroids decrease the thickness of airway wall in asthma, then forced vital capacity (FVC), which reflects the functional changes at low lung volume, should decrease less during induced bronchoconstriction than flow at high volume. The study was conducted in 31 mild asthmatics under control conditions and during a methacholine challenge before and after 4-weeks treatment with inhaled fluticasone dipropionate (1.5 mg daily, 16 patients) or placebo (15 patients). After fluticasone dipropionate treatment, control forced expiratory volume in one second (FEV1), and maximal flow at 50% of control FVC during forced expiration after a maximal (Vmax,50) and a partial inspiration (V'p,50) significantly increased. During methacholine challenge, FVC decreased less than did FEV1 or V'max,50, and so did inspiratory vital capacity compared to V'p,50. Both the provocative dose of methacholine causing a 20% fall in FEV1 and the bronchodilator effect of deep inhalation significantly increased. The latter was assessed by means of the regression coefficient of all V'max,50 plotted against V'p,50. No significant changes in these parameters occurred after placebo. These data show that inhaled steroids remarkably blunt the occurrence of gas trapping during induced bronchoconstriction in mild bronchial asthma, possibly due to their effect on airway wall remodelling. (C) ERS Journals Ltd 2000.
AB - According to a recent hypothesis, airway smooth muscle regulates airway calibre mostly at high lung volume, whereas the mucosa and adventitia dimensions dominate at low lung volumes. It was thought that if inhaled steroids decrease the thickness of airway wall in asthma, then forced vital capacity (FVC), which reflects the functional changes at low lung volume, should decrease less during induced bronchoconstriction than flow at high volume. The study was conducted in 31 mild asthmatics under control conditions and during a methacholine challenge before and after 4-weeks treatment with inhaled fluticasone dipropionate (1.5 mg daily, 16 patients) or placebo (15 patients). After fluticasone dipropionate treatment, control forced expiratory volume in one second (FEV1), and maximal flow at 50% of control FVC during forced expiration after a maximal (Vmax,50) and a partial inspiration (V'p,50) significantly increased. During methacholine challenge, FVC decreased less than did FEV1 or V'max,50, and so did inspiratory vital capacity compared to V'p,50. Both the provocative dose of methacholine causing a 20% fall in FEV1 and the bronchodilator effect of deep inhalation significantly increased. The latter was assessed by means of the regression coefficient of all V'max,50 plotted against V'p,50. No significant changes in these parameters occurred after placebo. These data show that inhaled steroids remarkably blunt the occurrence of gas trapping during induced bronchoconstriction in mild bronchial asthma, possibly due to their effect on airway wall remodelling. (C) ERS Journals Ltd 2000.
KW - Airway inflammation
KW - Asthma
KW - Methacholine
KW - Respiratory mechanics
UR - http://www.scopus.com/inward/record.url?scp=0034037284&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034037284&partnerID=8YFLogxK
U2 - 10.1034/j.1399-3003.2000.15d11.x
DO - 10.1034/j.1399-3003.2000.15d11.x
M3 - Article
C2 - 10780760
AN - SCOPUS:0034037284
VL - 15
SP - 687
EP - 692
JO - European Journal of Respiratory Diseases
JF - European Journal of Respiratory Diseases
SN - 0903-1936
IS - 4
ER -