Table 1.

Characteristics of the Group A subjects.

	Smokers with COPD (SC; n = 19)	Smokers without COPD (S; n = 16)	Non-smokers (NS; n = 9)	p
Age, years	67 ± 9	67 ± 9	69 ± 4	NS
Smoking history, pack-years	47 ± 21	39 ± 23	–	NS
Smoking status, current/ex	10/9	4/12	–	NS
FEV1% pred	60 ± 31*	97 ± 11	98 ± 19	0.001
FEV1/FVC %	51 ± 17*	78 ± 6	79 ± 4	0.001

Values are expressed as mean ± SD.

The statistical analysis was performed using one-way ANOVA with Tukey as a post-hoc test.

*Significantly different from smokers without COPD and non-smokers (p < 0.001). NS: non-significant. –, not applicable.