Table 1.
Baseline characteristics of subjects who showed a downward shift in FEV1/FVC category between their baseline and final visits
| Subgroup | ||||||
|---|---|---|---|---|---|---|
| A (n = 390) | B (n = 82) | C (n = 239) | ||||
| LLN-Fixed- → LLN-Fixed+ | LLN-Fixed- → LLN + Fixed+ | LLN-Fixed + → LLN + Fixed+ | ||||
|
Non-smokers (n = 246) |
Smokers (n = 144) |
Non-smokers (n = 27) |
Smokers (n = 55) |
Non-smokers (n = 102) |
Smokers (n = 137) |
|
| Males, n (%) | 133 (54) | 65 (45) | 14 (52) | 16 (29) | 80 (78) | 79 (58) |
| Age, years (SD) | 64.9 (11.0) | 58.3 (9.3) | 53.0 (10.3) | 52.6 (9.1) | 63.6 (9.2) | 61.7 (9.0) |
| Baseline postbronchodilator FEV1/FVC (SD) | 0.75 (0.04) | 0.75 (0.04) | 0.75 (0.05) | 0.75 (0.05) | 0.64 (0.04) | 0.65 (0.04) |
| Baseline postbronchodilator FEV1, liters (SD) | 2.33 (0.76) | 2.33 (0.67) | 2.28 (0.60) | 2.10 (0.58) | 2.22(0.68) | 2.09 (0.66) |
| as % predicted* (SD) | 78.0 (14.8) | 76.8 (12.1) | 72.8 (14.3) | 71.6 (11.9) | 68.8 (12.2) | 67.6 (12.7) |
See Figure 2b for further illustration of subgroups
FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; LNN: lower limit of normal; SD: standard deviation
* based on Swanney prediction equations [6]