Combined use of exhaled hydrogen peroxide and nitric oxide in monitoring asthma.
Oxidative stress contributes to airway inflammation and exhaled hydrogen peroxide (H2O2) and nitric oxide (NO) are elevated in asthmatic patients. We determined the concentrations of expired H2O2 and NO in 116 asthmatic (72 stable steroid-naive, 30 stable steroid-treated, and 14 severe steroid-treated unstable patients) and in 35 healthy subjects, and studied the relation between exhaled H2O2, NO, FEV1, airway responsiveness, and eosinophils in induced sputum. Both exhaled H2O2 and NO levels were elevated in steroid-naive asthmatic patients compared with normal subjects (0.72 +/- 0.06 versus 0.27 +/- 0.04 microM and 29 +/- 1.9 versus 6.5 +/- 0. 32 ppb, respectively; p < 0.001) and were reduced in stable steroid-treated patients (0.43 +/- 0.08 microM, p < 0.05, and 9.9 +/- 0.97 ppb, p < 0.001). In unstable steroid-treated asthmatics, however, H2O2 levels were increased, but exhaled NO levels were low (0.78 +/- 0.16 microM and 6.7 +/- 1.0 ppb, respectively). There was a correlation between expired H2O2, sputum eosinophils and airway hyperresponsiveness (methacholine PC20). Exhaled NO also correlated with sputum eosinophils, but not with airway hyperresponsiveness. Our findings indicate that measurement of expired H2O2 and NO in asthmatic patients provides complementary data for monitoring of disease activity.
Department of Thoracic Medicine, National Heart and Lung Institute at Imperial College School of Medicine, and Royal Brompton Hospital, London, United Kingdom.
I
I
Horváth
L E
LE
Donnelly
A
A
Kiss
S A
SA
Kharitonov
S
S
Lim
K F
KF
Chung
P J
PJ
Barnes
D000280:Administration, Inhalation; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000627:therapeutic use; D000328:Adult; D001249:Asthma / Q000188:drug therapy / Q000378:metabolism* / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000378:metabolism / Q000503:physiopathology; D001985:Bronchial Provocation Tests; D016085:Bronchoconstrictor Agents; D004804:Eosinophils / Q000473:pathology; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D016166:Free Radical Scavengers / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism*; D008297:Male; D016210:Methacholine Chloride; D009569:Nitric Oxide / Q000378:metabolism*; D016877:Oxidants / Q000378:metabolism*; D018384:Oxidative Stress / Q000502:physiology; D012119:Respiration; D013183:Sputum / Q000166:cytology
D000305:Adrenal Cortex Hormones; D016085:Bronchoconstrictor Agents; D016166:Free Radical Scavengers; D016877:Oxidants; D016210:Methacholine Chloride; D009569:Nitric Oxide; D006861:Hydrogen Peroxide