Spirometric variable | Visit (months) | GOLD II | GOLD III | GOLD IV | p Values | ||
GOLD II vs GOLD III | GOLD II vs GOLD IV | GOLD III vs GOLD IV | |||||
Post-bronchodilator FEV1 change (litres) | 0 | 0.16 (0.17) | 0.10 (0.13) | 0.05 (0.08) | <0.001 | <0.001 | <0.001 |
3 | 0.15 (0.16) | 0.11 (0.13) | 0.06 (0.09) | <0.001 | <0.001 | <0.001 | |
6 | 0.16 (0.17) | 0.11 (0.12) | 0.07 (0.10) | <0.001 | <0.001 | <0.001 | |
12 | 0.16 (0.16) | 0.10 (0.12) | 0.06 (0.09) | <0.001 | <0.001 | <0.001 | |
Post-bronchodilator FVC change (litres) | 0 | 0.25 (0.33) | 0.25 (0.35) | 0.25 (0.32) | 0.983 | 0.865 | 0.877 |
3 | 0.25 (0.32) | 0.25 (0.32) | 0.26 (0.30) | 0.737 | 0.733 | 0.911 | |
6 | 0.24 (0.33) | 0.24 (0.30) | 0.24 (0.32) | 0.945 | 0.730 | 0.700 | |
12 | 0.24 (0.31) | 0.22 (0.32) | 0.19 (0.27) | 0.359 | 0.037 | 0.148 | |
Post-bronchodilator FEV1/FVC change (%) | 0 | 0.94 (4.39) | 0.04 (4.11) | –1.30 (4.47) | <0.001 | <0.001 | <0.001 |
3 | 0.74 (3.97) | 0.29 (3.94) | –0.88 (5.08) | 0.031 | <0.001 | <0.001 | |
6 | 1.10 (4.66) | 0.40 (3.88) | –0.51 (4.99) | 0.002 | <0.001 | 0.006 | |
12 | 1.05 (4.17) | 0.52 (3.91) | 0.11 (4.54) | 0.011 | 0.002 | 0.180 |
Data are given as mean (SD).
COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; GOLD, Global initiative for chronic Obstructive Lung Disease.