Asthma and Autoimmune Disease: What Is the Connection?
What causes asthma is not known. Asthma triggers depend on the type of asthma a person has and may include pollen, exercise, or an irritant. There is currently no cure for asthma, but avoiding the triggers and following a treatment plan can help manage it.
Explore this article for information on asthma, types of asthma, autoimmune diseases, and whether or not there is an overlap.
Asthma is a long-term condition that affects the airways of the lungs. With asthma, the immune system often overreacts to asthma triggers, causing inflammation in the airways of the lungs. This constricts the airways, making it difficult to breathe.
Asthma triggers vary from person to person and may include:
- air pollution or dust
- cleaning products and disinfectants
- cold outdoor air
- pets or pet dander
- physical activity
- strong emotions that can cause fast breathing
- smoke, including secondhand smoke
- tree, grass, or weed pollen
Although there is currently no cure for asthma, an asthma treatment plan can help manage the condition. A plan may include:
- daily medications to control symptoms and prevent asthma attacks
- quick-relief medications, such as rescue inhalers, to use during an asthma attack
- identifying and avoiding triggers
- cleaning your home regularly to reduce dust, pet dander, and other irritants
- not smoking
- exercising regularly
The word “asthma” usually refers to a collection of several different types of asthma, each with different causes and triggers. Knowing your type of asthma can lead to effective treatments and better disease management.
Types of asthma include:
- Adult-onset asthma: Symptoms of asthma begin in adulthood. Often, an event such as a respiratory virus triggers the onset.
- Allergic asthma: Asthma attacks are triggered by common allergens, such as pollen, dust, or pet dander.
- Asthma-COPD overlap: This is considered a combination disease wherein a person has both asthma and chronic obstructive pulmonary disease (COPD).
- Exercise-induced bronchoconstriction: This happens when the airways narrow as a result of physical activity. It may or may not result in an asthma attack.
- Non-allergic asthma: This type of asthma is triggered by non-allergen sources. So, instead of pollen in the air, for instance, stress or cold air triggers an asthma attack.
- Pediatric asthma: This is asthma that occurs in children younger than 5 years old.
- Occupational asthma: When irritants to the lungs are present at work, they can trigger symptoms of occupational asthma.
There is also a subtype of asthma called eosinophilic asthma. It is caused by a specific type of white blood cell from the immune system contributing to the symptoms of the condition.
Autoimmune diseases occur when the body’s immune system mistakenly thinks that a body part or system is a foreign invader and attacks it. With autoimmune diseases, the body produces autoantibodies that accidentally attack healthy body cells.
Autoimmune diseases can develop as a result of an environmental trigger, such as a virus, that causes the immune system to “misfire” and attack the body instead. For example, some research suggests a connection between having the Epstein-Barr virus and later developing multiple sclerosis, which is an autoimmune disease.
Other types of autoimmune diseases have no clear cause or trigger. Examples of autoimmune diseases include:
Asthma and autoimmune diseases both result from dysregulated immune systems.
The immune system is designed to help protect it from foreign substances that could cause harm. With asthma, however, the immune system overreacts to something bothering the lungs.
When a person with asthma breathes in pollen, for example, the immune system overreacts to it by sending extra mucus to the lungs and causing swelling in the airways.
Normally, if there is an actual threat to the lungs —
such as a dangerous virus or bacterium — this response can help kill it. With asthma, though, no actual danger is present, and the reaction instead causes the airways to become clogged and constricted.
Over time, asthma attacks can also lead to the airways becoming permanently thicker. This causes an increase in symptoms during asthma attacks because less air can pass through. Mucus can also cause the airways to clog up more easily.
Eosinophils are a specific type of white blood cell thought to be involved in the primitive part of the immune system. Eosinophils can be both helpful and harmful in some immune system reactions.
With eosinophilic asthma, eosinophils are responsible for causing the airway inflammation, swelling, and mucus production that give rise to difficulty breathing. In asthma, the eosinophils are part of an immune system response that causes more harm than good.
In general, eosinophils are not often present in the airways, which may explain why they can be harmful in cases of asthma.
Eosinophils are also involved in some autoimmune diseases, such as eosinophilic granulomatosis with polyangiitis. This is a condition that affects the blood vessels.
Here are some questions that people often ask about asthma and autoimmune diseases.
Do people with asthma have weakened immune systems?
What type of disease is asthma?
Asthma is a chronic, lifelong disease that involves the immune system often overreacting to environmental triggers. It is not considered an autoimmune disease, though the immune system is involved.
Current research is focusing on finding out if there is more of an autoimmune role in asthma.
Who gets asthma?
According to the Centers for Disease Control and Prevention (CDC), just under 25 million people — or 7.7% of the United States population — reported having active asthma in 2018.
Asthma can affect anyone at any age. According to the CDC, however, it is more common among:
- male children under 18 years of age
- females over 18 years of age
- non-Hispanic Black individuals
- non-Hispanic multiracial individuals
- Puerto Rican individuals
Both asthma and autoimmune diseases involve the immune system not working correctly. However, asthma is not considered an autoimmune disease.
With autoimmune diseases, the immune system attacks regular, healthy cells. For example, with type 1 diabetes, the body attacks the pancreas, which produces insulin.
In asthma, however, the body’s immune system reaction is exaggerated, causing asthma symptoms. The body often reacts to some kind of trigger — such as pollen, exercise, or an irritant in the lungs — and produces an immune reaction that causes swelling and mucus in the airways of the lungs.
One possible connection between asthma and autoimmune diseases is that white blood cells called eosinophils promote and regulate inflammation. Eosinophilic asthma involves an overproduction of eosinophils that cause airway inflammation. Eosinophils also play a role in autoimmune diseases, causing inflammation and other symptoms.