What Is Silent Asthma?

Asthma is a lung condition in which the airways become inflamed and narrowed. This narrowing restricts the amount of air that can move through the bronchioles and usually causes distinct breathing sounds such as wheezing and coughing.

In silent asthma, no wheezing or coughing is present. This may be a variation in asthma symptoms, or it could be a phenomenon that healthcare providers sometimes refer to as the "silent chest." Silent chest can be associated with severe forms of asthma, including status asthmaticus and fatal asthma.

This article discusses the causes of silent asthma as well as symptoms, diagnosis, treatment, and prevention.

Silent Asthma Symptoms

Silent asthma symptoms are similar to those of regular asthma, with the absence of coughing or wheezing. Symptoms may include:

• Distress, anxiety, or restlessness
• Fatigue
• Chest tightness
• Feeling short of breath
• Difficulty speaking

Severe symptoms that require immediate medical attention may include:

• Breathing retractions that look like an area of sinking or sucking in that occurs when breathing muscles are working hard (retractions may be most noticeable between the ribs or at the base of the neck)
• Rapid breathing
• Inability to talk due to difficulty breathing
• Cyanosis (bluish color around the lips or beds of the fingernails, which indicates poor oxygenation)
• Dizziness or passing out

Causes

A specific cause of asthma cannot always be identified. However, there are some known risk factors for the development of asthma:

• Genetics
• Allergies
• Environmental factors, such as exposure to pollution
• Respiratory infections
• Obesity

It's worth noting that the term "silent asthma" is not well-defined or researched. If you have been told that you have silent asthma by a healthcare provider, it could simply mean that you are have mild or moderate symptoms of asthma without wheezing or coughing.

However, at some point, almost everyone with asthma will experience wheezing and coughing, even if you don't experience the more audible symptoms all the time.

One reason you may not have wheezing or coughing is that your airways have not tightened so much as to restrict air movement through your bronchioles, or at least not enough to produce these characteristic breathing noises.

It's also possible that you are wheezing, but it is so faint that it's difficult to hear. Not everyone with asthma experiences the same symptoms, and your symptoms may vary depending on the day and circumstance.

Diagnosis

If your healthcare provider suspects asthma based on your symptoms, physical examination, and medical history, they might order one or more of the following tests to confirm the diagnosis:

• Spirometry: A spirometry test measures how much air you move in and out of your lungs. Spirometry may be performed before and after administration of bronchodilator (a medication that dilates the airways).
• Bronchoprovocation tests: Measures how your spirometry is affected when you are exposed to certain allergens.
• Peak expiratory flow: Measures how much you can exhale with maximum effort.
• Fractional exhaled nitric oxide (FeNO): Measures inflammation in your airways by increasing the amount of nitric oxide you exhale.

Treatment

There are several differ treatment options for asthma, including medication, procedures, and avoiding triggers.

Triggers

Triggers are anything that brings on asthma symptoms. Identifying and avoiding asthma triggers can be an important part of your treatment plan.

Potential asthma triggers include:

• Allergens (i.e., mold, pollen, pet dander)
• Air pollution
• Chemicals or toxins (i.e., tobacco smoke, cleaning supplies, paint fumes)
• Exercise

Medications

Long-acting or maintenance medications for asthma work to prevent asthma attacks. These include:

• Corticosteroids (fluticasone, mometasone, budesonide)
• Biologics (benralizumab)
• Leukotrine modifiers (montelukast)
• Mast cell stabilizers (cromolyn)
• Long-acting beta agonists (salmeterol)

Short-acting or rescue medications for asthma relieve the symptoms of an acute asthma attack. They include:

• Short-acting beta agonists (albuterol, terbutaline)
• Oral corticosteroids (prednisone)

Bronchothermoplasty

Bronchothermoplasty is a procedure used to treat severe asthma that cannot be controlled with other treatments. It involves using a bronchoscope to apply heat to the muscles of the bronchioles, which thins and weakens the muscles, making it more difficult for them to constrict during an asthma attack.

Preventing Asthma Attacks

The best way to prevent asthma attacks is to stick to your asthma action plan. In particular, make sure to use your long-acting asthma medications on time and as prescribed, and identify and avoid triggers.

Summary

While wheezing and coughing are classic symptoms of asthma, it is possible to have asthma without experiencing these symptoms. This is known as silent asthma. This form of asthma can include a mild to moderate variation of symptoms. However, if it occurs after a prolonged asthma attack or is accompanied by serious symptoms, such as cyanosis or loss of consciousness, it could be a life-threatening condition called silent chest.

If you suspect silent chest, call 911 or go to your nearest emergency room.

A Word From Verywell

Silent asthma can be a particularly frightening condition because the lack of obvious symptoms makes it more difficult to diagnose. While there is no cure for asthma, symptoms can be managed once a diagnosis is made. The best way to manage the condition is to create an asthma action plan with a qualified healthcare provider and stick to it.