Stages of COPD and What to Expect
August 30, 2023

Stages of COPD and What to Expect

Knowing how your chronic obstructive pulmonary disease (COPD) diagnosis may progress can help you manage your condition and communicate with your doctors.

The group of related lung conditions called COPD causes airway blockage and trouble breathing. COPD is progressive, which means that the condition will continue to develop, causing more severe symptoms over time.

Doctors and other experts now break down COPD into grades, previously referred to as stages, based on your symptoms, history, and testing results.

Doctors use the global initiative for chronic obstructive lung disease or GOLD standards to describe the severity of your COPD. Grading using the GOLD system helps doctors make treatment decisions that can help them breathe better and take steps to slow the progression.

How is COPD divided into stages?

For many years, people living with COPD were assigned a stage according to the GOLD system.

The GOLD system included four distinct stages, including:

  • Mild (GOLD 1)
  • Moderate (GOLD 2)
  • Severe (GOLD 3)
  • Very severe (GOLD 4)

These stages were assigned based on the results of a spirometry test.

What’s a spirometry test and how is it used to stage COPD?

A spirometry is a simple test you perform in a doctor’s office. To take the test, you breathe in as deeply as possible and then exhale into a tool called a spirometer.

The doctor will measure your forced expiratory volume in 1 second (FEV1). In simple terms, this is how much air you push out within 1 second.

They will then calculate the percentage difference between your actual FEV1 score and the predicted value (how much air you should be able to push out, based on your age, height, weight, and other factors) to help stage your COPD.

In general, the lower your FEV1 percentage score, the higher your COPD stage will be.

How is COPD divided into grades and groups?

In 2011, the guidelines were updated to better consider the multiple factors that may affect COPD. The updated GOLD standards assign a grade and a group by considering:

  • the results of a spirometry test (your FEV1 score)
  • your symptoms, according to the modified Medical Resource Council dyspnea scale or a COPD Assessment Test (CAT)
  • your health history
  • how often you experience flares

Instead of assigning you a stage based on the spirometry test alone, your doctor will assign a grade (1–4) based on the spirometry results and a group (A–D) based on your symptoms, history of flares, and other considerations.

This update better reflects the complexity of living with COPD. For example, you may only experience a mild decrease in your FEV1 score (Grade 1) but manage more severe symptoms and frequent flares (Group C or D). On the other hand, someone with a very severe FEV1 decrease (Grade 4) may only experience mild symptoms (Group A or B).

After considering your spirometry test, your responses to the questionnaires, your history, and your experience of flares, your doctor will assign you to a group and a grade.

  • Group A: lower risk, fewer symptoms; 1 or fewer flares in last year; Grade 1 or 2
  • Group B: lower risk, more symptoms; 1 or fewer flares in last year; Grade 1 or 2
  • Group C: higher risk, fewer symptoms; 2 or more flares in last year; Grade 3 or 4
  • Group D: higher risk, more symptoms; 2 or more flares in last year; Grade 3 or 4

Overall, the higher the grade, the more likely a person is to manage more severe symptoms. The following explains how each part of the grading system operates.

Spirometry test

Your results on the spirometry test will help to determine your grade.

  • Grade 1: FEV1 score greater than or equal to 80% of the predicted value
  • Grade 2: FEV1 score between 50% and 79% of the predicted value
  • Grade 3: FEV1 score between 30% and 49% of the predicted value
  • Grade 4: FEV1 score less than 30% of the predicted value


Your doctor will evaluate your symptoms in several ways.

They may ask you to complete a modified Medical Resource Council dyspnea scale (mMRC). This questionnaire asks you to rate your breathlessness from mild (only during exercise) to severe (interferes with daily living). Your answers will be assigned a score between 1 (mild) and 4 (severe).

They may ask you to complete a COPD Assessment Test (CAT). This questionnaire asks questions related to cough, phlegm, chest tightness, breathlessness, activity limitation at home, confidence leaving home, sleep, and energy. Your answers will be assigned a score between 0 and 40.

A higher score on either of these questionnaires will contribute toward being placed in a higher group.

Health history

They may also ask you about:

  • Your prescribed medications and how often you take them
  • Your smoking history
  • Your vaccination status
  • How often you visit the emergency room or hospital for treatment
  • Other health conditions


Your doctor will want to know how often you experience flares or exacerbations. This means a time when your symptoms increase. If you’ve had no flares or only one in the last year, you may be assigned to group A or B, depending on other factors. If you’ve had two or more flares in the last year you’re likely to be assigned to group C or D.


How long does each stage last?

There’s no set length for how long a COPD stage will last. A lot will depend on your overall health, how you respond to treatments and other factors. In general, COPD slowly progresses, meaning it could take years before you move from milder to more severe symptoms.

What can you do to avoid progressing to the next stage?

While you cannot reverse or stop the disease from progressing completely, there are things you can do to manage symptoms and slow progression.

As part of treatment, you should consider trying to stop smoking, staying up-to-date on vaccinations to avoid illness, and limiting exposure to pollutants or irritants.

Keeping regular care appointments and following a treatment plan determined in cooperation with your doctor can also help.

At what stage do you need oxygen?

You’re more likely to need oxygen at the higher grades. But a doctor will likely recommend it if your blood oxygen levels drop too low.


COPD grading helps doctors evaluate your symptoms and identify the best treatment options for you.

The grade and group you’re assigned rely on test results from a breathing test as well as your symptoms and history. Lower scores on the test and more severe symptoms typically mean you’re at a higher COPD grade.

While there’s no way to completely cure or prevent COPD, you can manage symptoms and slow progression by working with your doctor to find the best treatment plan and lifestyle modifications for you.

Authored by Jenna Fletcher
Medically Reviewed by Adithya Cattamanchi, M.D.