Asthma can be genetic, though not all cases of asthma are inherited. Asthma has a range of other causes and risk factors.
Asthma affects people of all ages and genders. According to the Centers for Disease Prevention and Control (CDC), 8.3 percent of people in the United States have asthma. However, some people may be more likely to develop asthma than others.
In this article, we look at whether different types of asthma have genetic links, other causes and risk factors of asthma, and treatments.
All types of asthma can have a genetic component. Some different types of asthma include:
- adult-onset asthma
- exercise-induced bronchospasm
- allergic asthma
- nonallergic asthma
- occupational asthma
- asthma with chronic obstructive pulmonary disease
A person is more likely to develop asthma if they have a family history of the condition. This means that asthma can be genetic. Some researchers describe it as a "highly heritable disease."
According to a 2014 review study, genetic factors account for around 70 percent of a person's risk of developing asthma, meaning that genes play a large role in whether or not a person develops the condition.
However, genetics are not the only cause of asthma. Some people develop it when they have no family history of the condition. Likewise, a person may have a genetic tendency toward asthma but never actually develop it.
Genetics play less of a role in asthma development later in life, so adult-onset asthma and occupational asthma are slightly less dependent on genes.
A person can also develop asthma without any genetic predisposition for the condition. In fact, many environmental factors can cause a person to develop it.
Both genetics and environment play a role in the development of asthma, but scientists still do not know the exact causes. That said, they have identified a number of triggers for asthma symptoms.
Asthma triggers can vary from person to person and may include:
A number of risk factors can increase a person's chances of developing asthma.
Genetics, or family history of asthma, raise a person's likelihood of developing asthma at some point in their life.
Other risk factors for asthma include:
- being overweight
- having allergies or other allergy-related conditions
- frequent exposure to secondhand smoke
- exposure to other forms of pollution, such as exhaust fumes
- exposure to occupational irritants, including chemicals and dust
Asthma symptoms and their severity vary by person. Some may have symptoms frequently, while other people may only experience them occasionally.
Asthma symptoms can include:
- chest tightness
- difficulty breathing
- shortness of breath
Sometimes, triggers can cause a short period of worsening symptoms called asthma attacks. When a person has an asthma attack, their bronchial tubes constrict.
During an asthma attack, the symptoms of asthma may become severe and need a rescue inhaler or, in some cases, emergency medical attention.
Symptoms of an asthma attack include:
- a feeling of the chest rapidly tightening
- rapid breathing
- a blue tint to the skin and nails
- shortness of breath not related to physical activity
- chest retractions
- an inability to take a full breath
Not all people with asthma have all of these symptoms. Also, just because a person has these symptoms, it does not mean that they have asthma.
Asthma treatments aim to help a person manage the symptoms and prevent asthma attacks. Treatments may also lessen the long-term damage to the lungs that can occur with poorly controlled asthma.
A doctor may recommend a combination of treatment methods.
Long-term medical treatments for asthma can include:
- long-term inhaled asthma control medications, including corticosteroids, combination inhalers, and bronchodilators
- allergy medications
Doctors may also prescribe fast-acting, short-term medications for asthma attacks. These can include:
- oral or intravenous steroids to reduce airway swelling in severe attacks
- fast-acting bronchodilators
- short-acting beta antagonists, such as albuterol inhalers
Also, a doctor will likely recommend that a person with asthma try some lifestyle modifications to help control their symptoms.
Lifestyle modifications that a person with asthma can try may include:
- identifying and avoiding triggers
- using air conditioning to avoid outdoor asthma triggers
- cleaning the home regularly to avoid dust and mold
- covering the mouth and nose in cold weather
- managing stress and strong emotions
Asthma has genetic components, but it can also have other causes and risk factors, especially in adult-onset asthma.
People can usually manage their asthma well using medications. However, some people may find their asthma symptoms difficult to control.
In such cases, it is best for people to identify their triggers and try to avoid them as often as possible.