Reduced Airway Distensibility, Fixed Airflow Limitation, and Airway Wall Remodeling in Asthma

The airways of individuals with asthma are less distensible than normal and it has been assumed that this may be due to airway remodeling associated with chronic inflammation, although there are currently no available data directly relating these two aspects of asthma. We have therefore carried out a study of the relationship between airway distensibility ( Δ Vd) and subepithelial reticular basement membrane (RBM) thickening as an index of airway remodeling, in a group of patients with relatively mild but symptomatic asthma. Our methods included a cross-sectional study of Δ Vd in patients with mild to moderate atopic asthma, with matched airway biopsy for structural components. We confirmed that Δ Vd was lower in patients with asthma than in normal individuals (19.8 ± 1.1 versus 24.1 ± 1.5; p < 0.05) and that RBM thickness was increased in patients with asthma (9.1 ± 2.2 versus 7.7 ± 1.2 μ m; p < 0.01). There was a negative correlation between Δ Vd and RBM thickness in asthma (r = − 0.37, p = 0.03) and po...