Table 9. Patient characteristics of exacerbators, non-exacerbators and controls at study start [mean ± (SD)].
| Variable | Exacerbators (n=90) | Non-exacerbators (n=113) | Controls (n=51) |
|---|---|---|---|
| Female/male | 11/79* | 25/88 | 30/21** |
| Age at Baseline | 65.0 (6.8)* | 64.4 (8.6) | 59.5 (7.5)** |
| GOLD stage 0 | 24 | 27 | |
| GOLD stage 1 | 11** | 41 | |
| GOLD stage 2 | 25 | 24 | |
| GOLD stage ¾ | 30** | 21 | |
| Number of pack years | 31.6 (26.3)* | 26.4 (25.6) | 6.1(13.6)** |
| Current smoker | 27* | 40 | 7** |
| Ex-smoker | 45*, ** | 39 | 10 |
| Never smoker | 18* | 34 | 34** |
| BMI (kg/m2) derived | 22.6 (3.1)* | 23.1(3.3) | 24.0 (3.2) |
| FEV1 (L) | 1.66 (0.74)*, ** | 1.87 (0.65) | 2.28 (0.57)** |
| FEV1 post (L) | 1.77 (0.73)*, ** | 2.00 (0.66) | 2.38 (0.59)** |
| FEV1/FVC (%) | 58.5 (16.8)*, ** | 64.1 (15.3) | 79.9 (5.0)** |
| FRC (L) | 4.11 (1.37)* | 3.83 (1.37) | 3.03 (0.75)** |
| FVC (L) | 2.89 (0.77) | 3.08 (0.78) | 3.00 (0.80) |
| FVC Post (L) | 2.98 (0.72) | 3.12 (076) | 2.99 (0.78) |
| IC (L) | 2.14 (0.57) | 2.23 (0.60) | 2.24 (0.56) |
| RV (L) | 3.37 (1.39)*, ** | 3.16 (1.87) | 2.23 (0.50)** |
| TLC (L) | 6.24 (1.28)* | 6.06 (1.46) | 5.25 (1.06)** |
| DLCO (mmol/ kPa x min) | 19.2 (5.4)* | 19.3 (5.8) | 22.9 (4.5)** |
*, significantly different from controls (P<0.05); **, significantly different from non-exacerbator group (P<0.05). GOLD, global initiative for chronic obstructive lung disease; BMI, body mass index; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; IC, inspiratory capacity; RV, residual volume; TLC, total lung capacity; DLCO, diffusion capacity for carbon monoxide.