Understanding COPD Progression: GOLD Stages Explained

Chronic obstructive pulmonary disease (COPD) is a progressive lung disorder characterized by chronic inflammation of the airways and lung tissue. This inflammation leads to swelling and structural damage that obstruct airflow, making breathing increasingly difficult.

Because COPD typically worsens over time, clinicians assess its severity using the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification. The GOLD system divides COPD into four stages—GOLD 1 (mild) through GOLD 4 (very severe)—based on airflow limitation (FEV₁) and the frequency of exacerbations.

Healthcare providers often combine patient‑reported questionnaires with spirometry, a lung‑function test that measures the forced expiratory volume in one second (FEV₁). These tools help predict symptom burden and the risk of future flare‑ups.

Explore the interactive infographic below to see how symptoms evolve across each GOLD stage and what you can expect as COPD progresses.