Chest
Clinical Investigations: AsthmaAirways Remodeling Is a Distinctive Feature of Asthma and Is Related to Severity of Disease
Section snippets
Subjects
We studied a group of 34 patients (age range, 18 to 55 years) with bronchial asthma as defined by the American Thoracic Society11 in our outpatient clinic (Table 1). We included lifetime nonsmoking patients with no respiratory infection or spontaneous asthmatic relapses in the 4 weeks prior to study. Respiratory symptoms were controlled with inhaled β2-agonists on a daily basis or as required. Patients requiring theophylline, steroids, or sodium cromoglycate were excluded. Baseline FEV1 had to
Results
In asthmatic subjects, baseline FEV1 values ranged from 75.7 to 137.0% (mean±SD: 101.2± 16.5%). Moreover, bronchial responsiveness of asthmatics to M ranged from severe to very mild: PC20 M values ranged from 0.15 to 14.4 mg/mL (mean±geometric SEM: 1.69±1.25 mg/mL). In healthy subjects, FEV1 baseline values ranged between 93.0 and 117.0% (mean±SD: 108.1±8.4%) and bronchial responsiveness to M was not measurable.
According to the asthma severity score, 14 asthmatics (female/male [F/M]: 4/10) were
Conclusions
We found a clear cutoff between the thickness of the subepithelial layer of asthmatics compared with that of healthy subjects. Thus, we confirmed that airway remodeling is a very distinctive and characteristic pathologic finding of bronchial asthma. Moreover, we demonstrated that in a large group of asthmatic patients treated with only inhaled β2-agonists on demand or on a regular basis, the degree of subepithelial layer thickness is highly related to clinical severity of asthma. However, we
ACKNOWLEDGMENTS
The authors gratefully acknowledge Drs. Gian Franco Consigli, Angelo Casalini, and Maria Vittoria Tonna of the Bronchoscopy Unit of the Rasori Hospital, Parma, for performing bronchoscopy procedures; Ms. Elena Neri, Department of Respiratory Disease, University of Parma, for performing pulmonary function testing; and Ms. Elizabeth de Young, Language Center, University of Parma, for reviewing the text.
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