GOLD-0
One of the stages of chronic obstructive lung disease (COPD), according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD).
GOLD-0 is stage 0 in the GOLD classification of COPD and indicates 'at risk' for COPD.
GOLD-0 is characterized by chronic cough and sputum production.
Lung function, as measured by spirometry (a test of the air capacity of the lungs),is still normal.