Table 2.
Airway inflammation data. All data are median (q1, q3) unless stated.
| COPD | Older healthy control | Younger healthy control | P | |
|---|---|---|---|---|
| Number of patients where sputum was induced, n (%) | 64 (93) | 28 (97) | 22 (100) | 0.529 |
| Number of patients with adequate sputum used in analysis, n (%) | 58 (90) | 26 (93) | 16 (73) | 0.096 |
| Total cell count, ×106/mLa | 4.3 (1.7, 6.7), n = 51 | 2.3 (1.4, 3.8), n = 23 | 1.7 (1.1, 3.2)*, n = 15 | 0.005 |
| Viability, % | 81 (67, 93) | 79 (67, 89) | 67 (59, 76)* | 0.015 |
| Neutrophils, % | 65.0 (43.0, 82.5) | 39.6 (27.8, 60.0)* | 10.8 (7.8, 28.4) ∗† | <0.001 |
| Neutrophils, 104/mL | 244 (78.4, 599) | 79.2 (33.1, 227)* | 22.2 (6.8, 41.6) ∗† | <0.001 |
| Eosinophils, % | 1.0 (0.3, 2.8) | 0.3 (0.0, 0.5)* | 0.1 (0.0, 0.4)* | <0.001 |
| Eosinophils, ×104/mL | 5.1 (0.8, 16.7) | 0.6 (0.0, 1.6)* | 0.0 (0.0, 0.6)* | <0.001 |
| Macrophages, % | 28.4 (12.5, 47.5) | 49.1 (34.8, 68.8)* | 81.3 (64.6, 89.5)* | <0.001 |
| Macrophages, ×104/mL | 78.0 (48.6, 139.5) | 117.0 (69.1, 161.3) | 137.3 (57.5, 194.1) | 0.144 |
| Lymphocytes, % | 0.3 (0.0, 0.8) | 0.8 (0.0, 1.8)* | 1.0 (0.0, 1.9) | 0.019 |
| Lymphocytes, ×104/mL | 0.4 (0.0, 1.7) | 1.8 (0.0, 4.2) | 1.4 (0.0, 5.1) | 0.087 |
| Columnar epithelial cells, % | 1.6 (0.5, 2.5) | 1.2 (0.3, 2.3) | 2.9 (0.4, 6.5) | 0.557 |
| Columnar epithelial cells, ×104/mL | 5.6 (1.6, 10.4) | 2.3 (0.5, 9.8) | 4.5 (0.2, 21.1) | 0.461 |
| Squamous cells, % | 3.5 (1.2, 8.9) | 3.6 (2.2, 7.6) | 6.7 (3.4, 13.4) | 0.135 |
*P < 0.05 versus COPD; † P < 0.05 versus older healthy control.
aWhen sputum volume was small, a cell smear was prepared and total cell count and viability data were not collected.