Preventive effect of 2 and 10 mg of sodium cromoglycate on exercise-induced bronchoconstriction.
This double-blind, randomised and cross-over study was designed to compare the preventive effect against exercise-induced bronchoconstriction (EIB), defined as the percentage decrease in FEV1 > or = 15% after 6 min of exercise, of 2 mg and 10 mg of sodium cromoglycate (SCG), administered through a metered dose inhaler via spacer, in asthmatic children. Each of the 30 subject (age 11.6 +/- 3.2 years) was tested on five occasions. For inclusion, EIB in test1 was required. In tests 2 to 5, all subjects inhaled 2 mg or 10 mg of SCG 20 min and 120 min before exercise in a randomised order. In order to assess excretion of eosinophil protein X (EPX) accompanying EIB, urine samples were collected before and after exercise. The mean percentage fall in FEV1 (+/- SD) in test 1 was 26.8 +/- 9.8%. Inhalation of 2 mg and 10 mg of SCG 20 min before exercise provided a significant preventive effect in 83% and 77% and inhalation 120 min before exercise provided a preventive effect in 63% and 70%, respectively (n = 30). Variance analysis did not reveal a statistically different absolute fall in FEV1 after exercise when both doses (120 min before exercise) were compared (P = 0.356). In an unselected subgroup of 12 children, urinary EPX increased after the challenge without SCG premedication (test 1) (mean change: +48.7 micrograms/mmol creatinine, P = 0.034), whereas no significant increase was found in case of SCG premedication (mean change in microgram/mmol creatinine): 2 mg/20 min: +12.1; 2 mg/120 min: +8.5; 10 mg/20 min: -10.4 and 10 mg/120 min: -23.5; P > 0.1).


CONCLUSIONS
Administration of 10 mg of sodium cromoglycate is no more effective in preventing exercise-induced bronchoconstriction than 2 mg regardless of whether the medication is given 20 or 120 min before exercise. The preventive effect of sodium cromoglycate on exercise-induced bronchoconstriction in asthmatic children is associated with the inhibition of urinary eosinophil protein X excretion.
Storm van's Gravesande
K
K
University Children's Hospital Freiburg, Germany.
Mattes
J
J
Grossklauss
E
E
Zurmühl
A
A
Moseler
M
M
Kühr
J
J
D000280:Administration, Inhalation; D000293:Adolescent; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001250:Asthma, Exercise-Induced / Q000517:prevention & control* / Q000652:urine; D001798:Blood Proteins / Q000187:drug effects / Q000378:metabolism / Q000652:urine*; D016084:Bronchoconstriction / Q000187:drug effects*; D002648:Child; D004205:Cromolyn Sodium / Q000008:administration & dosage / Q000627:therapeutic use*; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D047208:Eosinophil-Derived Neurotoxin; D005080:Exercise Test; D006801:Humans; D012260:Ribonucleases / Q000187:drug effects / Q000378:metabolism / Q000652:urine*; D012882:Skin Tests; D016896:Treatment Outcome
D018927:Anti-Asthmatic Agents; D001798:Blood Proteins; D047208:Eosinophil-Derived Neurotoxin; D012260:Ribonucleases; D004205:Cromolyn Sodium