Age and physiological parameters in 100 patients with COPD categorised according to MRC dyspnoea grade
| Variable | MRC grade 3 (n = 32) | MRC grade 4 (n = 34) | MRC grade 5 (n = 34) | ANOVA (F) | p value |
|---|---|---|---|---|---|
| Age (years) | 69.3 (7.2) | 67.5 (8.3) | 73.2 (5.5) | 5.66 | <0.005 |
| FEV1 prebronchodilator (l) | 0.99 (0.38) | 0.91 (0.37) | 0.82 (0.36) | 1.81 | 0.2 |
| FEV1 (% predicted) | 40.8 (14.6) | 36.5 (15.6) | 37.0 (15.1) | 0.79 | 0.5 |
| ΔFEV1 (% predicted) | 4.2 (4.4) | 2.3 (3.3) | 2.6 (3.1) | 2.50 | 0.09 |
| FVC (l) | 2.57 (0.75) | 2.37 (0.68) | 1.92 (0.73) | 6.83 | <0.002 |
| Paco 2(kPa) | 5.90 (0.67) | 5.70 (0.75) | 5.96 (0.77) | 0.67 | 0.5 |
| Pao 2 (kPa) | 8.88 (1.09) | 8.65 (0.76) | 8.63 (1.45) | 0.49 | 0.6 |
| pH | 7.41 (0.02) | 7.41 (0.07) | 7.43 (0.02) | 1.58 | 0.2 |
FEV1 = forced expiratory volume in one second; FVC = forced vital capacity; Paco 2, Pao 2 = arterial carbon dioxide and oxygen tensions.