According to the Global Initiative for Obstructive Lung Disease (GOLD), the four stages of COPD are:
- Stage I: Mild COPD. Lung function is starting to decline but you may not notice it.
- Stage II: Moderate COPD. Symptoms progress, with shortness of breath developing upon exertion.
- Stage III: Severe COPD. Shortness of breath becomes worse and COPD exacerbations are common.
- Stage IV: Very severe COPD. Quality of life is gravely impaired. COPD exacerbation can be life-threatening.
So if the symptoms starts progressing in the above fashion that is if the disease progresses from a milder stage to a more severe stage, it can be considered that it is getting worse.