What is COPD?


Chronic obstructive pulmonary disease (COPD) is the name used to describe a number of lung conditions which make breathing more difficult by limiting the flow of air out of the lungs.

COPD is progressive (usually gets worse over time), and can be life-threatening, but it is preventable and treatable. There are 210 million people worldwide thought to be living with COPD, and it can affect each person differently. So if you’re confused by COPD or want to know more, click through our glossary below.

Stages of COPD

‘Stages’ (sometimes also known as ‘grades’) are used to roughly define the progression, or level, of COPD that a person has. It is not exact, but in general the stages can be characterized by:

Stage 1: Mild

  • Mild airflow limitation (difficulty breathing)
  • Chronic cough and sputum production (though not always)

Stage 2: Moderate

  • Worsening airflow limitation
  • Shortness of breath (sometimes referred to as dyspnea)
  • Exacerbation

Stage 3: Severe

  • Further worsening of airflow limitation
  • Greater shortness of breath
  • Reduced exercise capacity
  • Repeated exacerbation

Stage 4: Very severe

  • Severe airflow limitation
  • Greatly affects quality of life
  • Serious exacerbations

What causes COPD?

Tobacco smoking – smoking or inhaling second-hand smoke

Outdoor pollution – e.g. traffic pollution

Indoor pollution – e.g. open fires

Occupational hazards – e.g. building dust, chemical fumes

How COPD affects your lungs

COPD may affect the elasticity (stretchiness) of your airways, cause a build-up of mucus in your lungs, or restrict your airways resulting in a reduced capacity to empty your lungs. This makes it difficult to breathe.

Symptoms of COPD

Dyspnea – feeling breathless

Chronic cough – coughing that doesn’t go away

Chronic sputum production – long-term coughing or spitting up phlegm or mucus

What does COPD feel like?

If you don’t have COPD, try this exercise to show how it might feel: inhale a full breath and exhale out halfway. Immediately take in a full breath again, breathing out the same amount as before to half capacity, and repeat. Very soon breathing becomes uncomfortable and you become breathless, which is what COPD does to people every day.


Spirometry is the test used to diagnose COPD. During the test, you take a deep breath and blow out sharply into a spirometer, a device which measures how much air you can blow out and how quickly you can empty your lungs. This may be repeated to get an accurate measurement.

The COPD Dictionary

When first diagnosed with COPD, it’s easy to get confused by all the medical terms used by your doctor. Educating yourself about COPD is very important, but we understand that there can be times when it all gets a bit overwhelming.

Why not check out the COPD Dictionary. This handy tool aims to summarize all of those words and phrases that are often used when discussing COPD. We understand that it can be difficult to get your head around the condition and we want to make it as easy for you as possible. If however you don’t feel that this would be useful for you as you’re already familiar with COPD, then why not pass it on to friends and family; it could certainly help them understand it a bit better!

Check out the COPD Dictionary here.


If you have an exacerbation, this means that you have a sudden, significant change in your condition compared to how you normally feel, which can lead to a change in medication.

They can be triggered by various factors, such as viral or bacterial infections.

Symptoms of an exacerbation include any number of things. You might be feeling more breathless more often, wheezing a lot, or coughing up more phlegm or mucus.

Because each case of COPD is different, each exacerbation is different, so if you feel worried about a change in your condition you should seek medical advice to help you to manage your COPD.

Also read

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November 2016