Variability in the precursor proteins of collagen I and III in different stages of COPD

Respiratory Research

Table 1 Patient characteristics of the immunohistochemical samples

	Non-smokers n = 16	Smokers n = 20	COPD stage I-II n = 20	COPD stage IV n = 8	p-value
Age, years	65 (13)**	63 (8)	65 (7)	54 (8)	0.039
Sex M:F	8:8	15:5	16:4	5:3	0.096
Pack-years	0*	46 (20)	39 (14)	34 (18)	< 0.001
FEV1 l/s	2.96 (1.19)§	3.02 (0.71)	2.2 (0.54)	0.66 (0.24)	< 0.001
FEV1 %predicted	98 (15)	91 (9)#	68 (13)	21 (12)	< 0.001
FEV1 postbd	2.98 (1.1)	3.26 (0.81)	2.23 (0.38)	NA
FVC	3.44 (1.3)	3.59 (0.91)	3.51 (1.1)	1.78 (1.0)	< 0.001
FVC postbd	3.46 (1.21)	3.79 (1.1)	3.66 (1.16)	NA
FEV1/FVC %	86 (9)*	84 (11)#	60 (8)	37 (13)	< 0.001
DCO %predicted	91 (15)**	77 (15)§§	75 (10)	29 (8)	< 0.001
DCO/VA %predicted	89 (11)**	82 (12)§§	77 (21)	46 (11)	< 0.001

Mean (SD)
*The mean difference between non-smokers and smokers is significant at the 0.05 level, Dunnett t-test.
§ The mean difference between non-smokers and COPD-patients is significant at the 0.05 level, Dunnett t-test.
# The mean difference between smokers and COPD-patients is significant at the 0.05 level, Dunnett t-test.
** The mean difference between non-smokers and patients with severe COPD (GOLD stage IV) is significant at the 0.05 level, Dunnett t-test
§§ The mean difference between smokers and patients with severe COPD (GOLD stage IV) is significant at the 0.05 level, Dunnett t-test

ISSN: 1465-993X