Table I. Demographic Characteristics of the Study Population and Small Airway Epithelial Cells Recovered.
| Parameter | Normal non-smokers1 |
Normal smokers1 |
Smokers with COPD (GOLD I / II)1 |
|---|---|---|---|
| Number | 18 | 18 | 18 |
| Sex (male / female) | 14/4 | 12/6 | 15/3 |
| Self-described race (African / European / other) |
10/6/2 | 10/8/0 | 6/8/4 |
| Age | 41 ± 7 | 46 ± 5 | 50 ± 6 |
| Smoking history (pack-yr) | 0 | 31 ± 16 | 34 ± 17 |
| Urine nicotine (ng/ml) | 0 | 1099± 1217 | 894 ± 930 |
| Urine cotinine (ng/ml) | 0 | 1419± 1008 | 1381±732 |
| Carboxyhemoglobin (%) | 0.7 ± 1 | 3.4 ± 2.5 | 3.2 ± 1.6 |
| Pulmonary function tests2 | |||
| FVC | 105 ± 9 | 109 ± 15 | 103 ± 19 |
| FEV1 | 106 ± 9 | 109 ± 15 | 82 ± 18 |
| FEV1/FVC | 82 ± 5 | 82 ± 4 | 64 ± 6 |
| TLC | 98 ± 9 | 102 ± 14 | 105 ± 23 |
| DLCO | 97 ± 10 | 93 ± 8 | 77 ± 16 |
| Number of airway epithelial cells recovered (× 106) |
5.3 × 106 | 6.7 × 106 | 5.3 × 106 |
| % Total cells epithelial |
99.8 ± 0.4 | 99 ± 0.8 | 96 ± 1 |
| Inflammatory | 0.2 ± 0.4 | 0.5 ± 0.8 | 4 ± 1 |
| % Epithelial cells3 | |||
| Ciliated | 71.5 ± 6.0 | 72.6 ± 6.1 | 66 ± 8 |
| Secretory | 7.1 ± 3.4 | 10.2 ± 3.1 | 18 ± 6 |
| Basal | 15.2 ± 3.7 | 10.9 ± 3.2 | 7 ± 3 |
| Undifferentiated | 5.9 ± 1.8 | 5.8 ± 4.0 | 9 ± 1 |
1
For the criteria for the study groups, see Methods.
2
FVC - forced vital capacity; FEV1- forced expiratory volume in 1 sec; DLCO - diffusing capacity for carbon monoxide; TLC - total lung volume; all values are presented as % predicted except for FEV1/FVC presented as % observed.
3
Compared to differential of 43% ciliated, 10% secretory, 27% basal and 20% undifferentiated in the large airway epithelium of non-smokers31.