What are the four stages of COPD (chronic obstructive pulmonary disease)?

What is COPD?

COPD is the name for a group of lung conditions – including chronic bronchitis and emphysema – that cause the airways to become narrowed, making it difficult to breathe air out of the lungs. It’s estimated that about 300 million people have the condition worldwide.

What is the GOLD assessment system for COPD? 

GOLD stands for Global Initiative for Chronic Obstructive Lung Disease, which is an organization that issues international guidelines for COPD care. Doctors all over the world use the GOLD guidelines when deciding how best to treat and manage their patients with COPD.

The GOLD system assesses COPD using the Refined ABCD Assessment Tool, which considers:

  • Spirometry result – to confirm the initial COPD diagnosis and measure airflow obstruction
  • Your symptoms and how they impact on your life
  • Your risk of having an exacerbation (flare-up), which is when your symptoms worsen suddenly.

From this your COPD is classified with a number from Grade 1 to Grade 4, and a letter from Group A to Group D. These give your doctor valuable information on how to monitor and treat your COPD. They’ll also be mindful to identify and treat promptly any other illnesses you have that might impact on your COPD.

 

The four stages of COPD: GOLD COPD grades 1 to 4

Grades 1 to 4 tell your doctor about your level of airflow obstruction, as measured by spirometry. In this simple breathing test a machine called a spirometer is used to measure:

  • The total volume of air that you can breathe out in one go – called the forced vital capacity (FVC)
  • How much air you can breathe out in the first second of a hard exhale – called the forced expiratory volume in 1 second (FEV1).

People with obstructed airways have a reduced FEV1 for their age. A COPD diagnosis is confirmed if your FEV1/FVC is less than 70%. Your doctor will grade your COPD from the four stages of COPD, 1 to 4 – Mild, Moderate, Severe and Very Severe – depending on how reduced your FEV1 spirometry score is for your age as follows:

GOLD COPD Grade 1    Mild              FEV1 is 80% or higher
GOLD COPD Grade 2   
Moderate     FEV1 is between 50% and 79%
GOLD COPD Grade 3    Severe          FEV1 is between 30% and 49%
GOLD COPD Grade 4    Very severe  FEV1 is less than 30%

Although these grades measure how obstructed your airways are, they’re not so helpful when it comes to choosing the best treatment for you. Originally doctors would only take your FEV results into consideration. However, to gain a wider understanding of your condition, they will now also assess your current symptoms, the chances of your COPD worsening, and any other health conditions you have.

GOLD COPD groups A to D

Your doctor will classify your COPD into one of four groups according to what symptoms you have, how mild or severe they are, and your risk of having an exacerbation (flare-up).

How is flare-up risk measured?

Quite simply, you’re more at risk of having a flare-up if you’ve had one recently. So if you’ve had no flare-ups of your COPD in the past year, your future flare-up risk is classified as low. If you’ve had only one flare-up in the past year and didn’t need to go into hospital, that also puts you at low risk.

If you’ve had to go into hospital because of your COPD in the past year, you’re at high risk of having another flare-up. Two or more flare-ups in the past year also put you in the high-risk category, even if you weren’t unwell enough to go to hospital on any of those occasions.

How are my symptoms assessed?

Usually your doctor will ask you to complete a short questionnaire about what symptoms you have and how they affect your life. The two most commonly used questionnaires are the:

  • COPD Assessment Test (CAT) – this asks you to rate how COPD affects your life in terms of cough, phlegm, mood, sleep, chest tightness, breathlessness, daily activities, energy and  when you’re out and about. Out of a total score of 40, a score of 5 or under would be expected in a healthy non-smoker. In the GOLD system a CAT score lower than 10 indicates ‘less systems’ and a CAT score of 10 or higher indicates ‘more symptoms’. 
  • Modified MRC Dyspnea Scale (mMRC) – this is a simpler measurement of breathlessness on a four-point scale. In the GOLD system an mMRC score of 0 to 1 indicates ‘less symptoms’ and an mMRC score of 2 or higher indicates ‘more symptoms’.

Your doctor will combine the flare-up risk and symptom score to determine your COPD Group, as follows:

GOLD COPD Group A Low flare-up risk, less symptoms
GOLD COPD Group B Low flare-up risk, more symptoms
GOLD COPD Group C High flare-up risk, less symptoms
GOLD COPD Group D High flare-up risk, more symptoms

 

What will my COPD Grade and Group mean for me?

Your Grade tells you what stage your COPD has reached. Your Group, along with any other medical problems, determines what treatment and management plan is best for you. Your doctor may adjust your treatment depending on how well your condition responds or if it worsens.

Everyone is different and Grade and Group don’t necessarily match up. For example a person with very severe but stable COPD and no flare-ups in the past year would have Grade 4, Group B COPD, whereas another person with very severe COPD who has needed hospital treatment twice in the past year for their condition would have Grade 4, Group D COPD. If there’s a big difference between Grade and Group your doctor might do some additional tests, such as a lung function tests or a CT scan, or review other medical problems you have to understand what’s going on with your COPD.

 

What are the symptoms at each of the stages of COPD?

Everyone is different and the symptoms and characteristics of COPD vary greatly from one individual to another. However the COPD stages broadly progress as follows:

  • Stage 1 (mild) COPD: It’s common to notice no symptoms until you’re in your 50s, so early COPD may show no symptoms at all. Or you may have a nagging cough that’s dry or produces a little phlegm. Shortness of breath after exercise is a common early symptom, though it’s easy to mistake that for just being a little out of shape.
  • Stage 2 (moderate) COPD: You may experience persistent coughing and phlegm (often worse in the morning), increased shortness of breath, tiredness, sleep problems, or wheezing. About one in five people have exacerbations that worsen their symptoms and cause the color of their phlegm to change. It can start to impact on your mental health, causing low mood and/or confusion.
  • Stage 3 (severe COPD): Early symptoms become worse and you might notice you’re having more flare-ups than before. You might find you have more chest infections than before, have a feeling of chest tightness and wheezing with everyday tasks. Some people might notice swelling in their ankles, feet, and legs.
  • Stage 4 (very severe or end-stage COPD): Symptoms from stage 3 worsen and become more persistent. Just breathing becomes an effort. Flare-ups might be more frequent and more severe. Other symptoms might include a ‘crackling’ when you breathe in, barrel chest, delirium, irregular or fast heartbeat, weight loss, or pulmonary hypertension.

 

Can I stop or slow down my COPD from worsening?

There’s no cure for COPD and it can become life-threatening. One study calculated that severe and very severe COPD could be associated with a reduced life expectancy of about eight years.

However the good news is that, the earlier COPD is diagnosed, the sooner you can start treatment and take action to slow its progression. Even at stage 4, with proper treatment COPD doesn’t have to limit how long you live. There are a number things you can do:

  • Stop smoking and avoid other airborne pollutants
  • Exercise safely
  • Be alert to the early warning signs of a flare-up and take action
  • Take an active role with your doctor in your treatment and regular reviews
  • Eat healthily.

Your doctor can help you create a plan to help you cope with any other medical conditions, including depression and anxiety which commonly affect people with COPD.

 

Don D. Sin. 2015. Should COPD stand for “comorbidity-related obstructive pulmonary disease”? https://erj.ersjournals.com/content/46/4/901 

COPD Stages and the Gold Criteria. 2019. https://www.webmd.com/lung/copd/gold-criteria-for-copd 

Healthline 2018. FEV1 and COPD: How to Interpret Your Results. https://www.healthline.com/health/fev1-copd#diagnosing-copd