Table 2.

Clinical Characteristics of Enrolled Subjects from Whom Lung Tissues Were Collected

	Nonsmokers Without COPD (Control-NS) (n=11)	Smokers Without COPD (Control-S) (n=7)	Patients with COPD (n=8)	Between-Group Differences (p value)
Age, y	58.36±4.048	63.14±1.550	59.38±1.362	0.5045
Sex ratio (F/M)	7/4	1/6	1/7	0.5045
Pack-year	0±0	25±6.583	8.750±5.154	0.0004
FEV1/FVC (%)	88.2±6.63	82.06±3.89	37.48±8.37	0.000
FEV1% pred	102.79±14.29	91.91±6.10	33.89±12.38	0.000

Note: Values are presented as the means ± SD.

Abbreviations: COPD, chronic obstructive pulmonary disease; pack-year, number of cigarettes smoked per day/20 (pack) × duration of smoking (year); FEV1, forced expiratory volume in one second; FVC, forced vital capacity; FEV1% pred, forced expiratory volume in one second per cent predicted.