Chest
Volume 122, Issue 1, July 2002, Pages 166-170
Journal home page for Chest

Clinical Investigations
Asthma
Vascular Involvement in Exercise-Induced Airway Narrowing in Patients With Bronchial Asthma

https://doi.org/10.1378/chest.122.1.166Get rights and content

Study objectives

The bronchial microcirculation has the potential to contribute to the pathophysiologic mechanisms of exercise-induced bronchoconstriction (EIB) in asthmatic patients. This study was designed to determine whether increase in airway vascular permeability is associated with the severity of EIB in asthmatic patients.

Design

Cross-sectional analysis.

Setting

University hospital. Participants: Twenty-five asthmatic patients and 12 normal control subjects.

Interventions

All asthmatics performed an exercise test, and the percentage of maximal fall in FEV1 and the area under the curve of the percentage fall in FEV1 plotted against time for 30 min (AUC0–30) were determined.

Measurements and results

The inflammatory indexes, NO levels, and airway vascular permeability index (ratio of albumin concentrations in induced sputum and serum) were examined in all subjects. The airway vascular permeability index was significantly higher in EIB-positive asthmatics (0.031 ± 0.009) than in EIB-negative asthmatics (0.020 ± 0.005, p = 0.0011) and normal control subjects (0.008 ± 0.003, p < 0.0001). We also found that there was a significant correlation between NO levels in induced sputum and the airway vascular permeability index (r = 0.525, p = 0.0101). Moreover, the airway vascular permeability index was significantly correlated with the severity of EIB (percentage of maximal fall in FEV1 [r = 0.761, p = 0.0002], AUC0–30 [r = 0.716, p = 0.0005]). However, this index was not significantly correlated with magnitude of eosinophilic inflammation.

Conclusion

Our findings suggest that increased airway vascular permeability due to excessive production of NO correlates with the severity of EIB in asthmatics, and that assessment of albumin flux in airway lining fluid stimulated by hypertonic saline solution is a sensitive predictor of the severity of EIB.

Section snippets

Subjects

The normal controls consisted of 12 subjects (mean age, 32.9 years; mean FEV1, 107.3%). All normal control subjects were healthy, lifelong nonsmoking volunteers who had no history of lung disease. All asthmatic patients satisfied the American Thoracic Society criteria for asthma.5 The clinical characteristics of these patients are shown in Table 1. The 25 asthmatics included in this study were all nonsmokers. Methacholine inhalation challenge testing was performed for all asthmatics. All

Results

Thirteen EIB-positive asthmatics and 12 EIB-negative asthmatics were well matched with respect to age, baseline lung function, and hyperreactivity to methacholine (Table 1). There were also no significant differences in temperature or humidity during the exercise test between EIB-positive asthmatics and EIB-negative asthmatics. However, the percentage of eosinophils and the concentration of ECP in induced sputum in EIB-positive asthmatics (% eosinophils, 20.6 ± 7.1%; ECP, 871 ± 187 ng/mL) were

Discussion

In the present study, higher levels of airway vascular permeability index were found in EIB-positive asthmatics than in EIB-negative asthmatics and normal control subjects. Moreover, there was a significant correlation between airway vascular permeability index and NO levels in induced sputum, the production of which was markedly increased in asthmatics. The role of excessively produced NO, if any, in the pathogenesis of bronchial asthma is under active investigation, and NO is known to be one

References (17)

There are more references available in the full text version of this article.

Cited by (61)

  • Exercise-induced bronchoconstriction update—2016

    2016, Journal of Allergy and Clinical Immunology
  • The effect of mouth breathing on exercise induced fall in lung function in children with allergic asthma and rhinitis

    2016, International Journal of Pediatric Otorhinolaryngology
    Citation Excerpt :

    Based on FENO level, which is a quantitative, noninvasive and safe method of measuring eosinophilic airway inflammation, children with asthma can be prescreened into a group with high FENO, indicating the need for EIB testing or into a group with near normal FENO for whom EIB is unlikely. Kanazawa et al. showed thatexcessive production of NO in the airways correlates with the severity of EIB in asthmatic patients so assessment of FENO values could lead to an increased understanding of individual features of asthma (phenotype) and the need for prevention and treatment of EIB [24]. Children in our study had in both groups comparative FENO values higher than normal (mean > 40 ppb), thus indicating the need for EIB testing in most of them.

View all citing articles on Scopus

Supported by grant-in-aid for Scientific Research (13670611) from the Ministry of Education, Science and Culture, Japan.

View full text