COPD is seriously underdiagnosed in Canada. Why?
There are estimates that up to a million Canadians are living with COPD without knowing it. Why is COPD so underdiagnosed? A person may not have symptoms, or assume their symptoms are related to age, a common respiratory infection or a “smoker’s cough”. People who no longer smoke may think they cannot develop COPD. Some people are diagnosed with asthma when their symptoms are caused by COPD. People with COPD are often also living with other health conditions like heart disease, which they may assume is the cause of their COPD symptoms.
A note about women and COPD
For a long time, COPD has been a disease associated with older, male smokers (or former smokers). Recent research has highlighted that although the number of women and men who die of COPD in Canada each year is about equal, COPD is likely underdiagnosed in women and that women experience more severe symptoms, have earlier disease onset and are more likely to have never smoked cigarettes. Over the past two decades, the number of hospitalizations for COPD in both younger (40 to 64) and older (65+) women has increased while the number of hospitalizations in older males has decreased.
When diagnosing COPD, your healthcare provider will consider your age, symptoms, medical history and results of a physical exam.
It’s important that your provider orders lung function testing or spirometry to confirm a diagnosis.
The importance of spirometry
Spirometry is a simple breathing test that measures the speed and the amount of air you are able to blow out of your lungs, using a device called a spirometer. Some doctors will offer spirometry testing in their office, while others will refer you to a lab or clinic that specializes in lung testing.
It is also important that the person administering the test has proper training on the use of a spirometer and in interpreting the test results. Your results will be compared against a “reference” or expected value, based on your age, height, sex and race.
Ruling out other health issues
Your doctor may order a CT scan or chest x-ray. These tests should not be used to diagnose COPD. If a CT scan or chest x-ray shows signs of possible COPD, spirometry should be used to confirm a diagnosis. A CT scan or chest x-ray may also help rule out other causes of the symptoms you’re experiencing or to determine if you have another condition at the same time, called a comorbidity.
If you are diagnosed with COPD, your doctor will also tell you the severity of your COPD: mild, moderate, severe or very severe. When determining what medications are best for you, your provider will consider your symptoms, your spirometry results, your history of exacerbations and any comorbidities that may be affecting your respiratory health.
Stages of COPD
Mild COPD
- You may have no symptoms.
- You may have breathlessness on moderate exertion and/or recurrent chest infections.
- Your symptoms have little or no effect on daily activities.
Moderate COPD
- Your daily activities are increasingly limited.
- You have increasing breathlessness, for example when walking a short distance on level ground. You might have to stop every few minutes to catch your breath.
- Your symptoms periodically become worse, requiring corticosteroids and/or antibiotics
- You have a phlegmy or productive cough.
Severe COPD
- You feel breathless even with minimal exertion. For example, you may get breathless getting dressed.
- Your daily activities are severely limited
- You have a chronic cough and you regularly cough up mucus/phlegm.
“End-stage” or very severe COPD
- You wheeze constantly and have trouble catching your breath even when you’re resting.
- You loose weight without trying.
- You may feel confused or delirious from lack of oxygen in your blood.
COPD vs. asthma
Some people who have asthma are misdiagnosed with COPD and some people are diagnosed with asthma when they actually have COPD. And some people have both asthma and COPD, which is referred to as asthma-COPD overlap syndrome, or ACOS. It’s important to know if your symptoms are being caused by asthma or COPD so you can receive the right treatment and know how to manage your symptoms.
What do COPD and asthma have in common?
Both are obstructive lung diseases, meaning breathing is difficult because of an obstruction or narrowing of the airways. Both COPD and asthma can cause coughing, shortness of breath and wheezing.
What are the differences between asthma and COPD?
COPD
- tends to develop in adults 40 years and older
- involves inflammation and damage to the structure and function of the lungs
- often a history of smoking or exposure to smoke
- symptoms are fairly consistent day to day but gradually get worse over time
- coughing is more likely to be “productive” (phlegmy)
- most flareups caused by respiratory infections or air pollution
- airflow obstruction is not fully reversible
- co-morbidities caused by lack of oxygen to cells and organs are common
- goals of treatment are to reduce symptoms, prevent exacerbations and decrease mortality
Asthma
- tends to develop earlier in life, often in childhood
- involves inflammation of the airways
- often a family history of asthma
- more likely to also have allergies or rhinitis (“hay fever”)
- symptoms will vary widely from day to day
- triggered by exercise, allergens or cold air
- coughing is typically “dry” (not phlegmy)
- inflammation of the airways can be reversed quickly using an inhaler
- doesn’t cause low blood oxygen levels except in cases of severe asthma attack
- goals of treatment are to reduce inflammation and control
Diagnosing COPD vs. diagnosing asthma
The results of a lung function test (spirometry) will indicate if your airways are obstructed. Once this is confirmed, your provider will determine if asthma or COPD is the cause. Your provider will consider your medical history including if you have a history of smoking. A history of smoking is more common in COPD.
You may be asked to use an inhaler that reduces inflammation in your airways (a bronchodilator) before repeating the spirometer test. The more “normal” your results after using the inhaler, the more likely it is that you have asthma as the damage caused by COPD is less reversible.
You may also be given medication to try over several weeks before you repeat testing using the spirometer.
This section was made possible by an unrestricted educational grant from Astra Zeneca Canada.