Exhaled nitric oxide and bronchial reactivity during and after inhaled beclomethasone in mild asthma.
The measurement of exhaled nitric oxide (ENO) is recognized as a marker of airway inflammation. ENO was measured in 10 nonsteroid-treated asthmatics at recruitment, during 3 weeks of inhaled beclomethasone (1000 microg/day) and for 3 weeks after withdrawal. Baseline ENO was increased in asthma compared with nonasthmatics (85.0+/-54.5 vs. 24.5+/-14.8 ppb, p < 0.0001). After inhaled steroid, there was no significant change in forced expiratory volume in 1 sec (FEV1) and forced vital capacity (FVC), but methacholine PC20 rose significantly (p = 0.0345). ENO (mean+/-SD; % baseline) fell after 1 week on steroid to 60.6+/-31.1 and rose to 95.3+/-46.1 at 1 week after withdrawal. ENO did not correlate with PC20 or FEV1. The changes in ENO and PC20 were inversely correlated (r2 = 0.325). ENO may be an index of airway inflammation and therapeutic response in bronchial asthma.
Silkoff
P E
PE
Division of Respiratory Medicine, Faculty of Medicine, The University of Toronto, Canada. silkoffp@njc.org
McClean
P A
PA
Slutsky
A S
AS
Caramori
M
M
Chapman
K R
KR
Gutierrez
C
C
Zamel
N
N
D000280:Administration, Inhalation; D000328:Adult; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D001507:Beclomethasone / Q000494:pharmacology / Q000627:therapeutic use*; D001944:Breath Tests; D016535:Bronchial Hyperreactivity / Q000188:drug therapy* / Q000503:physiopathology; D001985:Bronchial Provocation Tests; D018592:Cross-Over Studies; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D007249:Inflammation / Q000188:drug therapy; D008297:Male; D016210:Methacholine Chloride; D009569:Nitric Oxide / Q000032:analysis*; D014797:Vital Capacity / Q000187:drug effects
D016210:Methacholine Chloride; D009569:Nitric Oxide; D001507:Beclomethasone