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Causes & symptoms of COPD

More than 2 million Canadians are living with COPD. There are estimates that up to a million more are living with COPD without knowing it.


Symptoms of COPD

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


Causes of COPD

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.


The Canadian Lung Health Test

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.

This section was made possible by an unrestricted educational grant from Astra Zeneca Canada.