Chronic Obstructive Pulmonary Disease (COPD)

People who have chronic obstructive pulmonary disease (COPD) usually have some symptoms of both chronic bronchitis and emphysema. Your symptoms will change depending on the severity of your COPD.

Key symptoms include:

• Long-term (chronic) cough.
• Chronic mucus (sputum) production when you cough.
• Repeated episodes of acute bronchitis.
• Shortness of breath that is persistent and gets worse, occurs during exercise, and gets worse during respiratory infections, such as colds.

You may have a rapid, sometimes sudden, and prolonged increase in symptoms (cough, amount of mucus, and/or shortness of breath), especially if your COPD is mainly chronic bronchitis. This is called a COPD exacerbation. A COPD exacerbation can be life-threatening, and you may have to go to the hospital.

A number of medical organizations have classified COPD according to symptoms and lung function. Lung function is based on spirometry tests that measure how much air you can breathe out compared to a person without COPD (the predicted value). Spirometry can measure how much air you can breathe out in one second (forced expiratory volume, or FEV1) and the amount of air you can breathe out after taking a deep breath (forced vital capacity, or FVC).

The guidelines are all similar. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) uses the following classifications:

At risk for COPD

You are at risk for COPD if you have risk factors, such as smoking, and you have long-term (chronic) cough and mucus production. People at risk for COPD have normal lung function, as measured by FEV1.

Mild COPD (stage 1)

Symptoms of mild COPD usually include a chronic cough that often brings up mucus from the lungs.

People with mild COPD have impaired lung function, even though the FEV1 is 80% or more of predicted value. You may have no shortness of breath and may not know you have impaired lung function until a lung test is done that measures the value of FEV1/FVC.

Moderate COPD (stage 2)

In moderate COPD, you have some of the symptoms of stage 1, plus you may have:

• A chronic cough that is getting worse and that brings up a large amount of mucus from the lungs.
• Shortness of breath and fatigue with exercise and strenuous daily activities.
• An occasional COPD exacerbation, which is a rapid, sometimes sudden, increase in your usual shortness of breath or other symptoms.

People with moderate COPD have a FEV1 of 50% to 79% of predicted value. Early symptoms of COPD often are overlooked or considered part of getting older.

Severe COPD (stage 3)

In severe COPD, you have some of the symptoms of stages 1 and 2, plus you may have:

• Shortness of breath with even simple daily activities, such as getting dressed and eating.
• Weight loss.
• Repeated and sometimes severe COPD exacerbations that have an impact on your life.

People with severe COPD have greatly reduced lung function (a FEV1 of 30% to 49% of predicted value).

Very severe COPD (stage 4)

In very severe COPD, you have some of the symptoms of stages 1 through 3, plus you may have:

• Blue skin color (cyanosis), especially in the lips, fingers, and toes.
• Fluid buildup in the legs and feet (edema).
• Bloated abdomen.
• Confusion (because of too little oxygen and too much carbon dioxide in the blood).
• Life-threatening COPD exacerbations.

People with very severe COPD have a FEV1 of less than 30% of predicted value or 30% to 49% of predicted value plus chronic respiratory failure (carbon dioxide remains in the lungs).

Conditions with similar symptoms include heart failure and coronary artery disease.

Asthma is another lung condition that may have symptoms similar to COPD, and some people with COPD may have asthma. Although asthma and COPD have similar symptoms, the two conditions differ in a number of ways, including the age at which the conditions develop and what triggers a reaction.