Chronic Obstructive Pulmonary Disease (COPD Disease)
COPD is an umbrella term that could refer to emphysema and chronic bronchitis and, more commonly, a combination of these conditions. Asthma was once classified as a type of COPD and shares some of the same characteristics but it’s now considered a distinct chronic inflammatory disorder. The most common chronic lung disease, COPD affects an estimated 30 million Americans, and its incidence is rising. It now ranks fourth among the major causes of death in the United States.
COPD has four stages. The stages of COPD range from mild to very severe. COPD affects everyone differently. Because COPD is a progressive lung disease, it will worsen over time. Your doctor will categorize your COPD stage based on your COPD symptoms and results from your lung function tests.
4 Stages of COPD:
1: Mild COPD or Stage 1—Mild COPD with a FEV1 about 80 percent or more of normal.
2: Moderate COPD or Stage 2—Moderate COPD with a FEV1 between 50 and 80 percent of normal.
3: Severe COPD or Stage 3—Severe emphysema with a FEV1 between 30 and 50 percent of normal.
4: Very Severe COPD or Stage 4—Very severe or End-Stage COPD with a lower FEV1 than Stage 3, or people with low blood oxygen levels and a Stage 3 FEV1