Chronic obstructive pulmonary disease (COPD) may sound like a single condition, but it includes three kinds of lung disease:
- Chronic bronchitis
- Chronic obstructive asthma
All of them can make you feel breathless. Doctors use stages to describe how severe your COPD is. This system is called the GOLD staging or grading system. Your grade will affect what treatment you get.
The system looks at many things. The basic idea is to understand how severe your COPD is and what type of treatment you need.
What Is the GOLD System for Grading COPD?
The GOLD system bases the stage of your COPD on several things:
- Your symptoms
- How many times your COPD has gotten worse
- Any times you’ve had to stay in the hospital because your COPD has gotten worse
- Results from spirometry, a test that checks the amount of air and speed that you can exhale
GOLD stands for the Global Initiative for Chronic Obstructive Lung Disease. The National Heart, Lung, and Blood Institute, National Institutes of Health, and the World Health Organization started it in 1997.
GOLD helps raise awareness of COPD and works with doctors and other health experts to create better ways to prevent and treat this condition. It also creates the guidelines most doctors use to classify and treat COPD.
Spirometry and Your COPD Stage
Spirometry results are based on two measurements:
- Forced vital capacity (FVC). This is the largest amount of air you can breathe out after breathing in as deeply as you can.
- Forced expiratory volume (FEV-1). FEV-1 shows how much air you can exhale from your lungs in 1 second.
GOLD Stages or Grades
The original GOLD system used the term "stages" to refer to the different levels of COPD. Now they’re called "grades." Experts believe this new system allows doctors to better match patients with the right treatments. The original stages also relied only on FEV results. But now doctors consider other things, too.
Your doctor will assign grades to these four things:
- How severe your current symptoms are
- Your spirometry results
- The chances that your COPD will get worse
- The presence of other health problems
You’ll answer some questions, either on the COPD Assessment Test (CAT) or the Modified Medical Research Council (mMRC).
CAT scores range from 0 to 40, and mMRC scores have five grades. For example, if you report that you only get winded when you do hard exercise, you might have mMRC grade 0. If you report being so breathless you can’t even leave the house or get dressed, you could have mMRC grade 4.
To check how well your lungs work, your doctor will look at your spirometry results. These results have four grades, too:
- GOLD 1: Mild
- GOLD 2: Moderate
- GOLD 3: Severe
- GOLD 4: Very severe
Another thing that’s part of your overall COPD assessment is your exacerbation risk. An exacerbation is a time when your COPD symptoms get so much worse that you need to make a change in your medication. Your doctor might also call it a flare. These flare-ups are more likely if your spirometry result is GOLD 3 or GOLD 4.
Other Health Problems
Your doctor will consider other health problems you have, too. It’s all part of grading your COPD and deciding what type of treatment is best for you.
Based on all of these things – your symptoms, spirometry results, and exacerbation risk – your doctor will put your COPD into one of these groups:
Group A (GOLD 1 or 2): Your symptoms are very mild. Your FEV-1 is 80% or more. You might have had no flare-ups over the past year, or perhaps just one. You weren’t hospitalized for your symptoms.
Group B (GOLD 1 or 2):Your FEV-1 is between 50% and 80%. You have more symptoms than people in Group A. This is the stage where most people see their doctor for coughing, wheezing, and shortness of breath. You might have had one major flare-up, but you haven’t been in the hospital for your symptoms within the past year.
- Group C (GOLD 3 or 4): Air flow into and out of your lungs is severely limited. Your FEV-1 is between 30% and 50%. You’ve had more than two flare-ups in the past year, or you’ve been admitted to the hospital at least once.
- Group D (GOLD 3 or 4): It’s extremely hard for you to breathe in or out. You’ve had at least two flare-ups in the past year, or you’ve been hospitalized at least once. Doctors call this “end-stage” COPD. That means you have very little lung function. Any new flare-ups could be life-threatening.
You may hear people talk about the old system, which staged COPD based on your FEV-1 score alone. There were four stages:
- Stage 1: Mild – FEV-1 ≥ 80%: You may have no symptoms. You might be short of breath when walking fast on level ground or climbing a slight hill.
- Stage 2: Moderate – FEV-1 50-79%: If you’re walking on level ground, you might have to stop every few minutes to catch your breath.
- Stage 3: Severe – FEV-1 30-49%: You may be too short of breath to leave the house. You might get breathless doing something as simple as dressing and undressing.
- Stage 4: Very Severe – FEV-1 ≤ 30%: You might have lung or heart failure. This can make it hard to catch your breath even when you’re resting. You might hear this called end-stage COPD.
Can You Postpone Advanced or End-Stage COPD?
It depends on how advanced your COPD is and how well you respond to treatment. No two people are the same. But following these steps for a healthy lifestyle can help:
- Don’t smoke. If you do, get help to quit.
- Avoid unhealthy air. Keep away from dust, fumes, and smoke. Stay inside on bad air days.
- Get a yearly flu shot. Ask your doctor if you need the pneumonia vaccine, too.
- Eat healthy food. Talk to your doctor about how to keep your weight where it should be.
- Keep moving. Make sure you get enough exercise.
The BODE Index
The BODE Index staging system is an alternative or addition to the GOLD criteria. It measures how much emphysema impacts your daily life. It looks at four main areas:
- B for body mass index: This describes how much body fat you have, compared to your height and weight.
- O for obstruction of air: Your doctor can tell how damaged your lungs are by how well you do on pulmonary (lung) function tests.
- D for dyspnea (breathlessness): Your doctor will ask you a series of questions about how often you feel like you’re out of breath, and when.
- E for exercise capacity: This measures how far you can walk in 6 minutes.
Studies show the BODE Index gives doctors a good sense of your prognosis. And they can use those findings to see how well you’ll respond to medications, lung rehab therapy, and other treatments.