Table 3.

Results of histology investigations.

	Non-Persistent Airflow Limitation n = 45	Persistent Airflow Limitation n = 47	Control n = 36	p-Value Non-Persistent vs. Persistent Limitation	p-Value Non-Persistent Limitation vs. Control	p-Value Persistent Limitation vs. Control
Collagen I, % of the stroma showing reactivity in bronchial mucosa section	30 (20–60)	30 (20–60)	30 (20–70)	0.77	0.67	0.89
Collagen I, strength of the staining	1 (0–1)	1 (0–1)	2 (1–2)	0.53	0.86	0.59
Collagen IV, strength of the staining	1 (1–2)	1 (1–2)	2 (1–2)	0.99	0.27	0.3
α1 integrin, strength of the staining	1 (1–2)	1 (1–2)	2 (1–2)	0.31	0.13	0.61
α2 integrin, strength of the staining	1 (0–1)	1 (0–2)	1 (0–2)	0.66	0.24	0.12
Thickness of the reticular basement membrane of bronchial mucosa, μm	6.77 (5.85–7.81)	6.2 (5.5–7.3)	4.77 (4.3–5.41)	0.66	0.0002	0.0001

Table 3 footnote. Variables are presented as a median and interquartile range. The reticular basement membrane thickness was measured in n = 35 (78%) asthma patients with non-persistent airflow limitation, n = 36 (77%) of those with persistent airway obstruction, and n = 24 (67%) control. Statistics: continuous variables: one-way covariance analysis (ANCOVA) adjusted for age, sex, and body mass index; categorical variables: χ² test.