Asthma is a common condition that affects 25 million people¹ in the United States. It's also the leading chronic disease in children. While currently, there isn't a cure for asthma, it's possible to control it with medication and lifestyle changes.
Treating asthma involves the creation of an Asthma Action Plan (AAP).² This plan contains clear instructions on what to do when symptoms occur and when to take prescribed asthma medication. When creating treatment plans and AAP, doctors use the asthma severity chart.
Let's take a closer look at the classification of asthma severity.
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Before classifying the severity of asthma, it's important to identify the type of asthma. In adults, doctors diagnose two common types of asthma: allergic (also called early-onset) and intrinsic (also called non-allergic, eosinophilic, late-onset, or adult-onset).
When a person has non-allergic asthma, their symptoms occur in response to:
Viral respiratory infections
Drugs and food additives
In short, the asthma triggers aren't related to allergens, hence the name. Non-allergic asthma affects 10–33% of people³ with asthma. The symptoms of this are often more severe than the symptoms of allergic asthma.
When a person has allergic asthma, the triggers that cause the symptoms are allergens, such as dust mites, pollen, pet dander, and mold. Meanwhile, triggers of non-allergic asthma can worsen the symptoms of allergic asthma.
Allergic asthma treatment includes identifying the allergen and avoiding it whenever possible.
This type of asthma occurs in 50–80% of people³ with asthma and around 50% of people with persistent severe asthma. The condition often occurs together with allergic rhinitis (hay fever)
The AAP and treatment methods depend on the type of asthma and the classification of asthma severity.
To design a personalized asthma management plan, your doctor must identify your asthma's severity level.
According to the National Institutes of Health's National Asthma Education and Prevention Program (NAEPP),⁴ asthma can be intermittent and persistent. Persistent asthma is divided into mild, moderate, and severe.
Accordingly, there are four categories of asthma:
The treatment plan differs from category to category. It can also be different for adults and children.
Intermittent is the lightest category of asthma. The symptoms include:
Problems with breathing
A person with intermittent asthma has:
Symptoms no more than two days a week
Nighttime flare-ups no more than two times per month
Normal breathing test results
The main difference between intermittent and persistent asthma categories is the frequency of symptoms, nighttime flare-ups, and attacks.
It's important to understand that while people with intermittent asthma don't have symptoms as often as people with persistent asthma, the severity of these episodes isn't always mild.
For a person with this asthma category, the condition doesn't interfere with their daily activities or exercise. People can go on for weeks or even months without experiencing an attack.
The medication for intermittent asthma includes:
This "rescue" medication works by attaching itself to tiny proteins (beta receptors) in your airways and relaxing muscles within airway walls. This medication starts working within five minutes and relieves asthma symptoms for up to six hours.
While SABAs (also called bronchodilators) are the first line of treatment for asthma, they only relieve the symptoms. This medication doesn't do anything for the underlying cause, which is inflammation. If the person requires rescue medication more than twice a week, they also need anti-inflammatory therapy.
A doctor can suggest anti-inflammatory therapy if a person with intermittent asthma needs rescue meds more often than twice a week. Corticosteroids reduce airway inflammation and alleviate asthma symptoms.
Right now, there isn't any evidence that long-term use of ICSs for asthma comes with any significant risks.
Symptoms of persistent mild asthma are similar to symptoms of intermittent asthma. However, symptoms and flare-ups occur more frequently. A person with this condition may also experience asthma attacks.
When you have an asthma attack, you are experiencing a significant worsening of asthma symptoms. You can feel extreme tightness in the chest and an inability to draw air. Many people also feel panic and anxiety. Asthma attacks can come without warning.
A person who has persistent mild asthma experiences:
Symptoms more often than twice per week but not more than once a day
A minor impact on daily activities and sports
Asthma attacks (some people with persistent mild asthma may never experience attacks)
Nighttime flare-ups 3–4 times per month
The need to use SABAs less than three times per week
Normal breathing tests
Similar to intermittent asthma, the treatment for persistent mild asthma includes SABAs and ICSs. In some cases, a doctor may prescribe long-acting beta-2-agonists (LABAs).
Just as SABAs do, LABAs also relax airway muscles. However, the effect can remain for up to 12 hours (two to four times longer than with SABAs). A doctor may recommend using LABAs twice daily to relieve symptoms and prevent attacks.
Another medication patients with persistent mild asthma may need to take is leukotriene receptor antagonists (LTRAs).⁵ This medication works by blocking the effects of specific leukotrienes in your airways that cause bronchoconstriction. Some studies⁶ show that adding LTRAs to ICS therapy can improve asthma symptoms.
Unlike patients with intermittent asthma, people with persistent mild asthma often need to take asthma medication daily.
People with persistent moderate asthma usually have asthma symptoms, attacks, and flare-ups. The condition often limits their everyday activities and keeps them from participating in certain sports.
Patients with persistent moderate asthma:
Experience daily asthma symptoms
Have several asthma attacks per year
Use "rescue" medication every day
Have nighttime flare-ups one or more times a week but not every night
The breathing tests will not show normal results if you have persistent moderate asthma. The lung function test will usually demonstrate that your FEV1 is between 60% and 80%.⁷
The treatment for persistent moderate asthma can include:
When the doctor first diagnoses persistent moderate asthma, they may recommend low-dose ICS + LABA or medium-dose ICS. An alternative treatment is low-dose ICS + LTRA.
If this treatment doesn't work, your doctor may recommend medium-dose ICS + LABA or medium-dose ICS + LTRA.
Persistent severe asthma affects between 5% and 10% of people with asthma. It can have a significant impact on daily activities and reduce the quality of life. If not controlled properly, a person with persistent severe asthma:
Experiences symptoms throughout the day
Needs to use rescue medication several times a day, every day
Has frequent asthma attacks
Has flare-ups every night
Shows low scores on the breathing test (FEV1 under 60%)
To keep severe asthma under control, your doctor can prescribe ICSs, LABA, and bronchodilators. In some cases, they may add oral corticosteroids to the therapy.
Besides medication, for all categories of asthma, your doctor will recommend other treatment methods, which include strategies to avoid triggers. Patient education is an integral part of asthma treatment.
To determine whether your treatment works, your doctor may suggest taking an asthma control test. This test, along with breathing tests and regular checkups, can help monitor your responsiveness to asthma treatment.
By keeping the condition under control with lifestyle changes, it's possible to improve the quality of life significantly.
Your doctor can suggest several⁸ tests to diagnose asthma and test its severity. Before running these tests, they will review your family, personal, and medical history. Ideally, you should prepare a journal that documents your symptoms, flare-ups, and attacks over time.
If you’re visiting the doctor for the first time, they will explain how to keep a journal to monitor your condition.
This simple breathing test measures how much air goes into your lungs and how much goes out. During the test, you will breathe into a mouthpiece that's part of a device called a spirometer. The doctor will ask you to take a deep breath, hold it for a few seconds, and exhale forcefully into the mouthpiece.
Spirometry test measures two parameters:
FVC – expiratory forced vital capacity
FEV1 – forced expiratory volume in one second
The doctor can also look at these two parameters in the form of a ratio (FEV1/FVC ratio). Depending on how severe your asthma is, these parameters change.
FVC results can either be normal or abnormal. If you have asthma, you are likely to have abnormal test results. However, some people with asthma may show normal results. That's why spirometry is only one part of the comprehensive diagnostic tactics.
FEV1 results show how severe your asthma is:
80% or higher – normal (you either don't have asthma or have intermittent asthma or mild persistent asthma)
60% - 80% - moderate persistent asthma
Less than 60 % - severe persistent asthma
While a spirometry test is the simplest way to identify the severity of your asthma, the doctor can still suggest additional testing.
The peak flow meter measures the rate you exhale air out of your lungs. During the test, you need to breathe deeply and blow into the device as hard as possible. While it doesn't allow the doctor to diagnose asthma, a peak flow meter can help monitor your condition.
The peak flow device is small. You can use it at home and record the results to share with your doctor.
Results are split into the following zones :
Green zone (80–100% of your normal peak flow rate) – your asthma is under control.
Yellow zone (50–80% of your normal peak flow rate) – you need to take action according to your AAP.
Red zone (less than 50% of your normal peak flow rate) – you need to take rescue meds and contact your doctor.
If readings of the peak flow meter are regularly in the yellow or red zone, they indicate that the treatment doesn't match the severity of your asthma. In this case, the doctor needs to adjust the AAP.
To classify the severity of your asthma, the doctor will evaluate your symptoms. People with milder forms of asthma don't usually have asthma attacks. They experience common symptoms, such as wheezing, coughing, and difficulty breathing.
Patients who have persistent asthma may experience attacks. These attacks include worsening of the symptoms and usually require the use of "rescue" medication. The duration and frequency of attacks and symptoms can help the doctor understand which asthma category your condition falls into.
The classification of asthma severity is different depending on the age group:
Children 0–4 years of age
Children 5–11 years of age
Children over 12 years of age and adults
For example, nighttime flare-ups that occur less often than twice a month can indicate intermittent asthma in adults. Meanwhile, children who have flare-ups this often can be diagnosed with persistent mild asthma.
An asthma severity chart is an important instrument for diagnosing and treating different categories of this chronic condition. By classifying asthma correctly, it's possible to keep the disease under control and improve the patient's quality of life.
Speak to your doctor about the classification of your asthma severity. With the right approach to treatment, you can alleviate the symptoms and prevent asthma attacks.
Asthma facts and figures | Asthma and Allergy Foundation of America
Create an asthma action plan | American Lung Foundation
Could I have severe asthma? | Asthma.com
Guidelines for the diagnosis and management of asthma 2007 (EPR-3) | NIH: National Heart, Lung, and Blood Institute
Lung function tests | Asthma and Allergy Foundation of America
Types of asthma | American College of Allergy, Asthma & Immunology
Asthma | University of Michigan Health
Asthma attack | American College of Allergy, Asthma & Immunology
Types of asthma | Asthma.com
Take the asthma control test | Asthma.com
Lung function tests | Asthma and Allergy Foundation of America
Measuring your peak flow rate | American Lung Association
How severe is my asthma: Classifying asthma severity | Allergy and Asthma Network