Stage | FEV1/FVC | FEV1 Predicted | General COPD Symptoms |
---|---|---|---|
I (mild) | <0.7 | ≥80% | Chronic cough or sputum production may be present (but not always) |
II (moderate) | <0.7 | 50% ≥FEV1 <80% | Exertional dyspnea develops (cough and sputum production sometimes present); some patients may have frequent exacerbations |
III (severe) | <0.7 | 30% ≥FEV1 <50% | Greater exertional dyspnea, fatigue and repeated exacerbations |
IV (very severe) | <0.7 | FEV1 <30% or 50% predicted plus chronic respiratory failure | Symptoms worsen; potentially life-threatening exacerbations |