What are the Four Stages of COPD?

The signs and symptoms and the severity depending on the stage of COPD.

COPD (chronic obstructive pulmonary disease) is a group of diseases that cause an inflammatory reaction and irreversible damage in the lungs. The result is obstruction of normal airflow and breathing difficulties. Emphysema and chronic bronchitis are the most common diseases that makeup COPD. COPD is a lifelong disease with periods of flare-ups. It negatively impacts the quality of life and longevity.

During inhalation, air travels through the nose and/or mouth into the trachea (windpipe). The trachea further divides into tubes called bronchi. The bronchi branch out into smaller tubes called bronchioles. The ends of bronchioles open into little air sacs called alveoli, which aid in gas exchange. The alveoli are surrounded by blood vessels through which the exchange of gases, oxygen and carbon dioxide, take place.

Exposure to the causative factors of COPD lead to the infiltration of different types of white blood cells and inflammatory factors. This leads to tissue inflammation, damage, and increased mucus secretion in the airway and alveoli.

• Emphysema: Emphysema is a disease of the alveoli. There is irreversible damage to the alveoli making them less elastic. There is decreased exchange of gases leading to decreased oxygen in the blood. Eventually patients have severe difficulty breathing.
• Chronic bronchitis: Chronic bronchitis is a disease of the bronchus. The trachea can also be involved. Inflammation due to irritants causes inflammation leading to an increase in the number and size of mucus secreting glands. There is also damage to the airway cilia, which are small hair like structures that help clear mucus. As a result, there is also decreased clearance of mucus which accumulates and thickens, causing airway obstruction. Chronic inflammation also leads to narrowing of the airways.

• Tobacco smoking: accounts for 90% COPD risk
• Environmental factors:
  • Passive smoking
  • Indoor cooking with poor ventilation
  • Air pollution
  • Exposure to chemicals
  • Exposure to industrial dust and fumes
• Intravenous drug abuse
• Infections, such as HIV
• Genetic disorders, such as Marfan syndrome and alpha1-antitrypsin deficiency

• Stage I: Mild COPD
• Stage II: Moderate COPD
• Stage III: Severe COPD
• Stage IV: Very severe COPD

The signs and symptoms and the severity depend on the stage of COPD. They worsen during flare ups.

STAGE I:

Symptoms are mild and often missed but the damage to the lungs begins. Symptoms include:

• Persistent cough, which could be dry or accompanied with mucus that is clear, white, yellow or green
• Shortness of breath on exertion

STAGE II:

• Persistent cough with mucus that may be worse in the morning
• Shortness of breath even with mild routine activity
• Wheezing on exertion
• Disturbed sleep
• Fatigue

STAGE III:

Stage III has a bigger impact on the quality of life. The symptoms in stage III worsen considerably. Additional symptoms include:

• Frequent respiratory tract infections
• Swelling of the ankles, feet and legs
• Tightness in the chest
• Trouble taking a deep breath 
• Wheezing and other breathing issues when doing basic tasks

STAGE IV:

This is the final stage of COPD. Occurs after years of continuous damage to the lungs. Patients have worsened symptoms of stage III and frequent flare ups that are sometimes fatal. Patients have a very poor quality of life.  Symptoms include:

• Barrel shaped chest
• Constant wheezing
• Being out of breath
• Delirium
• Increased heart rate/heartbeat
• Loss of appetite and weight
• Increased blood pressure

The physician may recommend a series of blood and radiological tests, including a chest X-ray. A gold-standard test for COPD is the pulmonary (lung) function test (PFT).

• Short-term and long-term bronchodialators (inhalers)
• Oral steroids or steroid inhalers
• Medication to clear and thin the mucus, and clear the airway
• Antibiotics for infection
• Stop smoking and avoid exposure to other irritants
• Pulmonary rehabilitation
• Oxygen therapy
• Surgery in severe cases, including a lung transplant may be required
• Breathing exercises

COPD is not curable in any stage of the disease. With early diagnosis and treatment, the disease progression and flare-ups can be controlled and longevity optimized. Patients can live a good quality of life and are encouraged to exercise as is possible. The patients must quit smoking and avoid exposure to other environmental factors.