Marker | COPD stage# | Cause of mortality |
BMI | I–IV | All cause/respiratory |
FEV1 | I–IV | All cause/respiratory |
IC/TLC | I–IV | All cause/respiratory |
Exercise | ||
V’O2,peak | I–IV, tilted towards III–IV | Systemic |
6MWT | I–IV, tilted towards III–IV | Systemic |
Dyspnoea | II–IV | All cause/respiratory |
Decreased chronic Pa,O2 | III–IV | Systemic |
BODE | 0–IV | All cause/respiratory |
C-reactive protein | I–IV | All cause |
COPD: chronic obstructive pulmonary disease; BMI: body mass index; FEV1: forced expiratory volume in one second; IC: inspiratory capacity; TLC: total lung capacity; V’O2,peak: peak oxygen uptake during cardiopulmonary exercise test; 6MWT: 6-min walking test; Pa,O2: arterial oxygen tension; BODE: body mass index (B), obstruction (O), dyspnoea (D) and exercise endurance (E) index. #: Global Initiative for Chronic Obstructive Lung Disease–American Thoracic Society/European Respiratory Society COPD stages.