SEVERITY OF EXERCISE-INDUCED BRONCHOCONSTRICTION IS RELATED TO AIRWAYEOSINOPHILIC INFLAMMATION IN PATIENTS WITH ASTHMA

Citation
T. Yoshikawa et al., SEVERITY OF EXERCISE-INDUCED BRONCHOCONSTRICTION IS RELATED TO AIRWAYEOSINOPHILIC INFLAMMATION IN PATIENTS WITH ASTHMA, The European respiratory journal, 12(4), 1998, pp. 879-884
Citations number
25
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Respiratory System
ISSN journal
0903-1936
Volume
12
Issue
4
Year of publication
1998
Pages
879 - 884
Database
ISI
SICI code
0903-1936(1998)12:4<879:SOEBIR>2.0.ZU;2-I
Abstract
Exercise-induced bronchoconstriction (EIB) is widely prevalent in asth matic patients. Eosinophilic airway inflammation is considered to be a major factor in the pathogenesis of asthma. However, the effects of e osinophilic airway inflammation on EIB have been elucidated insufficie ntly. To examine the relationship between the severity of EIB and eosi nophilic inflammation, sputum induction and exercise challenge were pe rformed in 21 asthmatic patients. Significantly higher percentages of eosinophils and levels of eosinophil cationic protein (ECP) were found in induced sputum in EIB-positive asthmatics (median (range), eosinop hils: 23.5 (11.0-61.0)%; ECP: 1,475 (74.8-17,701) ng.mL(-1)) than in E IB-negative asthmatics (eosinophils: 6.0 (1.0-41.5)% (p=0.006); ECP: 2 70.6 (10.8-7,700) ng.mL(-1) (p=0.049)). There was a significant correl ation between the severity of EIB and the sputum eosinophil percentage (r=0.59, p=0.009) and the level of ECP (r=0.47, p=0.037). The area un der the curve of the forced expiratory volume in one second for 30 min after exercise correlated with the percentage of eosinophils (r=0.60, p=0.008) and the level of ECP (r=0.45, p=0.04). There was no correlat ion between airway responsiveness to methacholine on the one hand and EIB, sputum eosinophils or ECP on the other. In conclusion, these resu lts provide evidence that the severity of bronchoconstriction evoked b y exercise is more closely related to eosinophilic airway inflammation than airway hyperresponsiveness to methacholine in asthmatic patients .