Asthma-COPD Overlap

Asthma-COPD Overlap Syndrome (ACOS) is when you have both diseases. Each condition must be treated.

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Asthma is considered severe when it is difficult to treat and manage the symptoms.

Chronic obstructive pulmonary disease (COPD) is a collection of lung diseases that cause breathing problems and obstruct airflow. This group of diseases can include refractory (severe) asthma, emphysema and chronic bronchitis.

Most people with asthma will not develop COPD, and many people with COPD don’t have asthma. However, it’s possible to have both. Asthma-COPD overlap syndrome (ACOS) occurs when someone has these two diseases at once.

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Signs of ACOS include:

  • Difficulty breathing
  • Wheezing
  • Frequent coughing
  • Tightness in the chest
  • Excess phlegm
  • Feeling tired
  • Low physical tolerance for exercise
  • Shortness of breath during routine activities

Although symptoms may not always be severe, ACOS is serious and can be deadly. In 2014, chronic lower respiratory diseases – primarily COPD – were the third leading cause of death in the U.S., according to the Centers for Disease Control and Prevention. About 3,500 people die of asthma each year, nearly half of whom are age 65 or older.

People with asthma may not realize they also have COPD. Sometimes COPD isn’t diagnosed until it’s in the “moderate” stage, meaning they are experiencing frequent shortness of breath, coughing and heavier-than-normal mucus. Misdiagnosis can occur because the symptoms of COPD mimic those of asthma.


Asthma triggers often include allergens, such as pollendust mitescockroachesmolds and animal dander. Allergens can make COPD symptoms worse. And if left untreated, allergies and asthma can increase the chances for COPD in certain individuals. But COPD is not the same thing as asthma, and COPD is not caused by allergies or asthma. COPD is a collection of lung diseases. Sometimes asthma is part of the collection and sometimes it isn’t. However, COPD can result from long-term exposure to some of the same environmental risk factors – often in workplaces – that also can cause occupational asthma.

Smoking is the greatest risk factor for developing COPD. Smoking is a dangerous aggravation to all respiratory problems. It can decrease your life expectancy and interfere with your treatment plan. The most important thing you can do for your health is to stop smoking.


When someone has ACOS it’s possible to mistake asthma for COPD or vice versa and fail to recognize the presence of both conditions. If you have either severe asthma or COPD, you should request further testing to find out if you have ACOS. When these two diseases overlap, both diseases need to be treated.

A diagnosis of severe asthma means that the symptoms of your asthma are not responding well to medications typically used to manage asthma, such as inhaled corticosteroids. You will need special care and treatment to try to improve lung function and manage symptoms. It’s important to consider other illnesses at this point to see if there are additional factors contributing to the diagnosis of severe asthma.

COPD is diagnosed most frequently among certain groups:

  • People between the ages of 50 and 74
  • Current and former smokers
  • People with a history of severe asthma
  • People with long-term exposure airborne irritants, including industrial chemicals and tobacco smoke
  • People with a family history of COPD

While COPD has long been thought to be an ailment most frequently diagnosed in older white men, a 2013 report by the American Lung Association found that women are 37% more likely than men to have the disease and make up more than half the COPD deaths in the U.S.

Early diagnosis and treatment can change the course of the syndrome and slow its progression. An allergist can diagnose COPD and other conditions, such as asthma, by asking you about your medical history. Your allergist will also give you a physical exam that may include a quick breathing test, known as spirometry. This will measure how much air your lungs can hold and how quickly air moves in and out.

Your allergist also may suggest a chest CT scan and a chest X-ray. After determining the stage of your COPD and your asthma, ranging from mild to severe, your allergist will go over treatment options with you and discuss lifestyle changes and a treatment plan to help you feel better and improve lung function.

Treatment and Management

COPD is progressive, which means it gets worse over time. Asthma is a reversible condition when the right treatment is received at the right time. This makes early treatment important, especially when ACOS occurs.

If you have any signs of COPD, you should see an allergist. The earlier you get treatment, the better. Your allergist is specially trained to help you manage the chronic conditions of asthma, COPD or ACOS. It’s especially important to work with your allergist to manage symptoms and get the best care possible for your specific needs.

Treating ACOS isn’t a one-size-fits-all approach. Each patient receives a customized treatment plan. Treatment may include medication to reduce symptoms, supplemental oxygen and pulmonary (lung) rehabilitation. It may take some time to identify which medications work best for you. Lifestyle changes, such as exercise, breathing techniques and avoidance of air pollutants at home and at work, may also be recommended. For smokers, the most important part of treatment is quitting the use of tobacco.

Because respiratory illnesses such as the flu can cause serious complications in people with ACOS, you should get a yearly flu vaccine. A pneumococcal pneumonia vaccine is also recommended.

The sooner you see an allergist, the better. There is no cure for ACOS, and the early diagnosis of this syndrome can improve the overall health of your lungs. When more than one illness affects your breathing or if you have ACOS, your allergist will help you manage your symptoms and maximize your lung function. Don’t wait to find an allergist. Take steps now to improve your health and the quality of your life.