Table 5.
Lung function estimates in the linear mixed model according to smoking status
| Parameter | Intercept at 1st examination (95% CI) | Difference (p-value) | Slope (95% CI) |
|||
|---|---|---|---|---|---|---|
| Never smoker (N) | Former smoker (F) | Current smoker (C) | N–C | F–C | ||
| FEV1 (%-pred.) | 99.56 (93.69–105.42) | 94.12 (88.67–99.58) | 92.08 (86.62–97.53) | 7.88 (p = 0.053) | 1.95 (p = 0.610) |
0.32 (0.15 – 0.48) |
| FVC (%-pred.) | 101.11 (95.76–106.46) | 96.07 (91.09–101.04) | 95.10 (90.12–100.08) | 5.828 (p = 0.111) | 1.10 (p = 0.752) | 0.43 (0.28 to 0.58) |
| FEV1/FVC (%-pred.) | 97.46 (94.35–100.56) | 97.30 (94.41–100.20) | 96.17 (93.27–99.10) | 1.834 (p = 0.373) | 0.95 (p = 0.629) | − 0.07 (− 0.14 to − 0.00) |
| DL,CO (%-pred.) | 97.08 (91.10–103.05) | 96.34 (89.82–102.85) | 90.38 (81.65–99.11) | 6.69 (p = 0,183) | 5.57 (p = 0.250) |
-0.11 (-0.42 – 0.19) |
| DL,CO VA (%-pred.) | 100.24 (93.98–106.49) | 96.97 (91.05–102.89) | 87.82 (81.64–94.00) | 12.26 (p = 0.006) | 8.61 (p = 0.043) |
0.23 (-0.10 – 0.56) |
C: current smoker, CI: confidence interval, DL,CO: diffusion capacity for CO, DL,CO/VA: Krogh-factor, F: former smoker, FEV1: forced expiratory volume in the first second, FEV1/FVC: Tiffeneau-Index, FVC: forced vital capacity, N: never smoker, SD: standard deviation