
Doctors can use the Global Initiative for Chronic Obstructive Lung Disease (GOLD) system to stage or grade COPD. This system classifies the stage based on how obstructed your airflow is, which is measured by spirometry.
Spirometry is a type of pulmonary function test. It measures the capacity of your lungs using
- Forced vital capacity (FVC): This measures the maximum air volume a person can forcibly breathe out after drawing in the deepest breath possible.
- Forced expiratory volume in one second (FEV1): This measures the maximum volume of air a person can breathe out in the first second during an FVC.
Your spirometry grade can be 1, 2, 3, or 4, depending on your FEV1 score. The severity of your symptoms and your risk of flare-ups or exacerbations will also place you in one of four letter groups:
group A | fewer symptoms, low risk |
group B | more symptoms, low risk |
group C | fewer symptoms, high risk |
group D | more symptoms, high risk |
Your spirometric grade and letter group will help doctors determine how your condition is progressing.
The letters do not necessarily follow the same pattern as the numerical spirometric grades. For example, a person whose spirometric grade is 1 may not necessarily be in group A, with milder symptoms and a low risk for exacerbations. Even people with only mildly affected airflow may have more symptoms and a high risk for flare-ups.
Your doctor can help you understand your numerical and letter grades and how they will impact your treatment plan.

The stages of COPD, as laid out in the GOLD system, can be seen in the table below.
GOLD stage | Airflow obstruction severity | FEV1 score |
---|---|---|
1 | mild | equal to or greater than 80% of a typical score |
2 | moderate | 50–79% of a typical score |
3 | severe | 30–49% of a typical score |
4 | very severe | less than 30% of a typical score |
In its early stages, COPD may not cause noticeable symptoms. When they do appear, symptoms may include:
- shortness of breath
- coughing with mucus
- wheezing
- chest infections
- chest tightness or pressure
As the disease progresses, some people may also experience:
- weight loss
- chest pain
- swollen ankles due to fluid buildup
- bloody cough
- severe fatigue
- more frequent or severe flare-ups
Treatment for COPD focuses on managing the symptoms and preventing flare-ups.
If you smoke, quitting can slow COPD progression. Avoiding secondhand smoke and other respiratory irritants like air pollution is also essential.
Your doctor may also prescribe bronchodilator inhalers. Bronchodilators are medications that make breathing easier by relaxing the smooth muscles in your airways. Examples of bronchodilators include salbutamol (Ventolin) and ipratropium (Atrovent).
Additional treatments
- Inhaled corticosteroids: These reduce inflammation. Your doctor may administer them together with bronchodilators.
- Antibiotics: These can treat bacterial infections and reduce the risk of exacerbations.
- Pulmonary rehabilitation: A pulmonary rehabilitation program leverages education, exercise training, and nutrition advice to help you achieve your maximum level of independence.
- Vaccination: Vaccinations can reduce the risk of developing specific respiratory conditions, like influenza and COVID-19, in people with COPD. Doctors recommend vaccination for people at all stages of COPD.
Oxygen therapy
As COPD progresses, doctors
Surgery
People with advanced COPD may need to undergo surgical procedures if other treatments are ineffective. These procedures
- Bullectomy: This is surgery to remove damaged pockets in the lungs. It may improve lung function.
- Lung volume reduction surgery: This is surgery to remove small sections of damaged lung tissue.
- Lung transplantation: This is surgery to replace a damaged lung with a healthy lung from a donor.
According to the National Heart, Lung, and Blood Institute, COPD symptoms develop slowly and worsen over time. The speed at which the disease may worsen varies, but particular factors
- smoking
- being exposed to secondhand smoke
- being exposed to other harmful irritants like air pollution
- receiving a late diagnosis
- not following the treatment plan
COPD can cause shortness of breath, chest tightness, wheezing, and coughing. Depending on the stage, your airflow limitation can be mild, moderate, severe, or very severe.
One of the first-line treatments for COPD is quitting smoking. Other treatments include medications like bronchodilators, pulmonary rehabilitation, and oxygen therapy.
Talk with your doctor about ways to manage COPD symptoms and slow the progression of the disease.