Association of prebronchodilator and postbronchodilator spirometric measures with number of exacerbations and severe exacerbations per year, change in FEV1, dyspnoea scores and distance covered in 6 min walk test from phase 1 to phase 2 visit (5-year interval)
| Prebronchodilator FEV1/FVC <0.7 (PREO) | Postbronchodilator FEV1/FVC <0.7 (POSTO) | |||||
| Coef (95% CI) | P value | AIC | Coef (95% CI) | P value | AIC | |
| Exacerbations per year | 0.35 (0.31 to 0.4) | <0.001 | −893 | 0.38 (0.34 to 0.43) | <0.001 | −929 |
| Severe exacerbations per year | 0.14 (0.11 to 0.16) | <0.001 | −11608 | 0.14 (0.12 to 0.16) | <0.001 | −11614 |
| Change in FEV1, mL | −2.25 (−20.3 to 15.8) | 0.81 | 54 317 | 10 (−7.26 to 29.3) | 0.24 | 54 315 |
| Change in MMRC | 0.2 (0.12 to 0.27) | <0.001 | 1978 | 0.21 (0.13 to 0.29) | <0.001 | 1974 |
| Change in SGRQ | 1.92 (0.99 to 2.85) | <0.001 | 26 399 | 2.56 (1.62 to 3.5) | <0.001 | 26 387 |
| Change in 6-MWD, feet | −22.2 (−44.3 to 0.05) | 0.049 | 55 763 | −33.2 (−55.6 to 10.8) | 0.004 | 55 758 |