Classification of CoPd by severity Stage o(at risk) Chronic cough and sputum production Contact with harmful factors FEV1/FVC>70% Stage l(mild) FEV1/FVC <70% FEV] c 80 predicted uSually, but not always, chronic cough andClassification of COPD by Severity • Stage 0 ( at risk) – Chronic cough and sputum production – Contact with harmful factors – FEV1/FVC > 70% • Stage I( mild) – FEV1/FVC < 70% – FEV1  80 % predicted – usually, but not always, chronic cough and sputum production