Causes & symptoms of COPD

Emphysema and chronic bronchitis are the two conditions that contribute to COPD in most cases.

Emphysema develops over time and involves the gradual damage of lung tissue, specifically the destruction of the alveoli (tiny air sacs). Gradually, this damage causes the air sacs to rupture and create one big air pocket instead of many small ones. This reduction in the lung surface area traps air in the damaged tissue and prevents oxygen from moving through the bloodstream. This blockage causes the lungs to slowly overfill and makes breathing increasingly more difficult. A chronic cough is one of the most common symptoms of emphysema.

Bronchitis occurs when the airways in your lungs (your bronchi) become inflamed. This can cause severe coughing spells that bring up mucus, wheezing, chest pain and shortness of breath. Bronchitis that doesn’t go away is called chronic bronchitis.

People with COPD usually have one or more of the following symptoms:

• a cough that lasts a long time (longer than three months)
• a cough with mucus
• feeling short of breath, especially during physical activity
• respiratory infections (e.g., flu, acute bronchitis, pneumonia) that lasts longer than for others
• wheezing (a whistling sound when you breathe)
• feeling tired
• losing weight without trying

Smoking causes most — but not all — cases of COPD. It is estimated that about 15 to 20% of those who smoke will develop COPD, but only about 3 in 4 cases of COPD will occur in those who smoked.

Other causes of COPD include:

• exposure to occupational dusts and chemicals
• exposure to “biomass” smoke (for example, burning coal, wood or charcoal),
• exposure to second-hand smoke and
• inherited alpha-1 antitrypsin deficiency.

Long-term exposure to air pollution, frequent lung infections as a child and poorly managed childhood asthma are also associated with an increased risk of COPD.

If you are over 40 and smoke or used to smoke, you may be at risk for COPD. If you answer “yes” to any of the following questions, please consider speaking to your doctor or nurse practitioner about spirometry testing.

• Do you cough regularly?
• Do you cough up phlegm regularly?
• Do even simple chores make you short of breath?
• Do you wheeze when you exert yourself, or at night?
• Do you get frequent colds that persist longer than those of other people you know?

This test is for information purposes only. It should not replace a complete medical examination. If you think you may have COPD or are worried about your lung health, please see your doctor.