What is Asthma?

Asthma is a chronic (long-term) lung condition that affects your airways or bronchial tubes. It can cause your airways to narrow and their lining to swell and to produce extra mucus, which makes it more difficult to breathe. The narrowing of the airways causes you to feel short of breath, wheeze, or cough. [1] Asthma is there even when you don’t have any symptoms. 

Asthma can affect people of all ages. While it might be mild for some, for others it can be more severe. It is important to know that all severities of asthma can impact normal everyday activities and people with infrequent asthma symptoms can still have  life-threatening asthma attacks if their asthma is not treated appropriately.  

While there is no cure for asthma, it can be effectively managed. The symptoms can be controlled, [2] and the risk of attacks greatly reduced. Not everyone with asthma will have exactly the same symptoms and it can change over time. This is one reason why it’s important to have regular checks with your doctor or asthma nurse, so they can monitor your asthma and change your treatment if necessary.

Some of the common signs and symptoms of asthma include [2,3]:

  • Shortness of breath
  • A feeling of pressure, tightness, or pain in your chest
  • Coughing
  • A whistling or wheezing sound when you exhale (wheezing is especially common in children with asthma)
  • Attacks of coughing and wheezing that are worse when you have a cold, flu, or other respiratory illness
  • Trouble sleeping at night due to being short of breath, coughing, or wheezing

Not everyone who has asthma has exactly the same symptoms. Symptoms may occur at different times of the year and at different times during your life. Symptoms can also vary from mild to more severe. [4]

If your asthma is changing or flaring up, then you may find symptoms become worse than usual. You may find it more difficult to breathe, experience more wheezing, and need your medicine more often. [3]

When an asthma attack occurs, the muscles around the airways tighten [5] – this is sometimes called bronchospasm. Bronchospasm [6] makes your chest feel tight and makes it harder to catch your breath. You may make a whistling or wheezing sound when you try to breathe. The lining in the airways may become more inflamed and swollen, more mucus may be produced, and the mucus may be thicker than usual.

If you have mild asthma symptoms, taking your reliever inhaler should help you feel better within minutes. But if you have more severe asthma symptoms, you may need medical attention, as it can be life-threatening. [7]

Asthma is a long-term chronic condition, but when an asthma attack happens, it’s an “acute” occurrence. This means it’s a sudden and sometimes serious attack.

There are some early warning signs you can look for that may suggest an asthma attack is likely. The symptoms are usually mild, but can be useful to recognise so that you can do your best to prevent a full-blown, or more serious, asthma attack.

The early warning signs and symptoms [3,8] to look out for include:

  • More shortness of breath, especially if it’s at night
  • More mucus or sputum than usual
  • Needing to take your rescue inhaler more often
  • Weakness, fatigue, or lack of energy
  • Extreme tiredness when exercising
  • Wheezing and coughing after exercising
  • Worsening cough 
  • Decrease in your usual lung function (which can be measured by using a peak flow meter)
  • Allergies or a cold, including nasal congestion, sneezing, sore throat, and a headache

If you have a personal asthma action plan [9] in place, then you should adjust your medication in line with the instructions on your plan. If you don’t have an action plan, or you have the symptoms of an asthma flare-up, ask your doctor for advice. It’s important to have a personal asthma action plan – ask your doctor or asthma nurse for a personalized plan.

The exact cause of asthma is unknown and the triggers can vary from person to person. However, it is recognised that asthma sometimes runs in families, which means if your parent or sibling has asthma, you’re more likely to have it too. Environmental factors can also play a part. Asthma often starts in childhood, but it can also start in adults as well. 

Asthma often occurs as the result of an immune system response to an environmental allergen, such as pollen or dust mites. Not everyone exposed to the same allergen reacts to it or they may react differently. Although the reasons why a particular allergen affects one person more than others aren’t entirely clear, it’s possible that inherited genes may be involved.

Some risk factors [10] that can increase your chances of developing asthma include:

  • Genetics – having a family member, such as a parent or sibling, who has asthma
  • Having an allergy, such as hay fever, eczema, or a food allergy (these are known as atopic conditions)
  • Being a smoker
  • Being exposed to secondhand or passive smoke, including during childhood or pregnancy
  • Obesity
  • Having had a respiratory infection as an infant
  • Being born prematurely [11] or with a low birth weight

The airways to the lungs are normally open, allowing air to move freely in and out of the lungs. However, people who have asthma have sensitive airways that are irritated and inflamed. Asthma symptoms are caused when the airways tighten or constrict in response to triggers and can fill with mucus, resulting in less space in the airways to breathe through. The symptoms can be triggered by various irritants, substances, and circumstances. [12] 

Triggers for asthma symptoms may be different in different people. They may include:

  • Exercise, particularly during cold or dry weather
  • Exposure to smoke, pollution, or fumes
  • Respiratory infections such as colds or flu
  • Allergic reactions, such as to dust mites, animal fur, feathers, or pollen, in patients who are allergic to these things
  • Changes in weather, including cold air, thunderstorms, heat, humidity, or any sudden change in temperature
  • Taking some medicines, such as beta-blockers (used for some heart problems or in eye-drops for glaucoma), and, for some people with asthma, taking anti-inflammatory painkillers [13]
  • Experiencing strong emotions such as stress
  • Being exposed to mold, in people who are allergic to it
  • For some people with asthma, sulfites [14] and preservatives added to some foods and beverages, including dried fruit, shrimp, processed potatoes, beer, and wine
  • Gastroesophageal reflux disease (GERD), where stomach acid comes back up into your throat [15]

It’s important to get to know your personal triggers and avoid them, where possible, to help control your asthma. However, once asthma is treated with an anti-inflammatory medication, and symptoms come under better control, you will often not respond to your previous triggers as much. 

Unlike some other health conditions, there’s no single form of asthma – it affects different people in different ways. As knowledge and understanding has improved over the years, medical experts have identified various types.

Knowing which type of asthma you have can help you learn how to manage it better and, for some people, may help you avoid coming into contact with known triggers.

Allergic, or atopic asthma, is the most common type of asthma. [16] Up to 80% of people with asthma also have allergies [17], and having allergies puts you at higher risk for allergic asthma. For people with allergic asthma, symptoms or attacks can be triggered by allergens like pollen, dust mites, pet fur, or feathers.

Non-allergic, or non-atopic asthma, is a form of asthma that is not triggered by an allergy. This type often starts later in adulthood. [18] It is more common in people who are overweight.

Some adults, particularly women [19], can have their first asthma attacks as an adult. This tends to be a form of non-allergic asthma. This can include occupational asthma – a form of asthma caused by your occupation or work. This form of asthma results from or is triggered by exposure to fumes, chemicals, dust, or other triggers you encounter during the course of your work. Adult-onset asthma can also be triggered by stressful life events.

Some patients with asthma will develop “airflow limitation” that is constant and not reversible. This is called airway remodeling, which means that the airways change by becoming more thick and narrow. [20] It is more common in people who have smoked, but can also occur in non-smokers.

Obesity can play a role in causing asthma and make asthma symptoms worse and harder to control. [21] It causes a different type of inflammation in the airways. 

People with asthma of any type can have symptoms triggered by exercise or physical exertion. Symptoms can get worse both during and after exercising. [22]

Childhood asthma is common and first occurs during childhood. This type can get better or even disappear completely during teenage years or as you get older, although it also commonly returns during adulthood. [23] 

Severe asthma affects people intensely and can have a major impact on daily life. [24] You’re more likely to have severe asthma if your symptoms or attacks are ongoing despite taking higher doses of inhaled steroids or other medications, and you may need additional treatment.

Seasonal asthma only occurs at certain times of the year. Symptoms may flare up in the summer when pollen levels are high, or in the winter when the weather is very cold and respiratory infections are more common. [18]

If your doctor suspects you could have asthma, they’ll ask about your symptoms and suggest tests to diagnose it. They’ll look at your nose, throat, and upper airways, listen to your breathing using a stethoscope, and take a general medical history.

Lung function tests will be carried out to see how well your lungs work. Common tests used include:

  • Spirometry [25] – where you blow into a machine that measures how fast you can breathe out and how much air you can hold in your lungs.
  • Peak flow test [26] – where you blow into a small handheld device, and it measures how quickly you can breathe out.
  • FeNO test [27] – where you breathe into a machine that measures the level of nitric oxide in your breath (this can highlight some types of inflammation in the lungs or elsewhere) Learn more in GAAPP’s FeNO educational flyer!

Sometimes, you may have a chest x-ray to rule out other causes of your symptoms.

Asthma severity [4] is measured by how difficult asthma is to treat.

Mild asthma: This is sometimes defined by doctors as asthma that is well-controlled with low-dose corticosteroid medication, but the term “mild asthma” is more commonly used for people who don’t have frequent or severe asthma symptoms. Even if you think your asthma is mild, you can still have severe attacks, so it is important to take a preventer or controller inhaler.

Moderate asthma: Asthma that is well-controlled with low-dose combination of corticosteroids with long-acting beta-agonist medications.

Difficult-to-treat: Asthma that is uncontrolled despite treatment with medium or high doses of corticosteroids plus long-acting beta-agonist medications. This form of asthma is difficult to treat due to several reasons:

  • Treatment that isn’t working due to strength or action of medications
  • Continual issues with following a treatment plan
  • Not taking your inhaler correctly or regularly
  • Additional health issues, including chronic rhinosinusitis or obesity

Severe asthma: Some people have asthma that is uncontrolled despite regularly taking high doses of corticosteroids plus long-acting beta-agonist medications, and having other problems addressed where possible. This is often due to a different type of asthma that doesn’t respond as well to normal asthma inhalers, and may benefit from additional treatment. 

Asthma treatment and medicines help to control symptoms, so you can live an active and normal life. As everyone experiences asthma differently, your doctor will put together an asthma treatment plan designed specifically for you.

The two ways that inhalers for people with asthma can be used are:

  • Reliever or rescue inhaler – this is used to treat your symptoms when they occur and usually provides relief within minutes. It can also be used before exercise. In the past, rescue inhalers contained only a bronchodilator such as albuterol. Although these inhalers will relax your lung muscles making it easier to breathe, they do not treat your asthma or prevent you from having severe attacks.  In many countries, people with asthma can be prescribed an anti-inflammatory reliever (AIR). This contains an inhaled corticosteroid as well as a bronchodilator, which as well as relaxing your lung muscles making it easier for you to breathe, also treats the inflammation in your airways that is causing your asthma symptoms and attacks. 
  • Daily preventer or controller inhaler – this contains an anti-inflammatory corticosteroid, sometimes combined with a long-acting beta-agonist medicine and is used daily, as prescribed, to reduce the amount of inflammation and sensitivity in your airways. People with moderate or severe asthma need to use a daily preventer or controller inhaler to help control asthma symptoms, stop them from occurring, and reduce the risk of asthma attacks.

International asthma guidelines recommend that every person with asthma aged 6 years and older should be taking an inhaler containing a corticosteroid, to reduce the risk of having a severe attack. Many people with asthma need only a low dose of inhaled corticosteroid, either as an anti-inflammatory reliever inhaler or as a daily anti-inflammatory inhaler. These low dose inhalers are very safe to use, and as well as controlling your symptoms, they protect you from having severe attacks. 

People whose asthma symptoms or attacks are not well-controlled with a low-dose corticosteroid inhaler should be taking a corticosteroid inhaler or combination corticosteroid plus beta-agonist inhaler every day, as well as a reliever inhaler. 

There is also a reliever-preventer combination option in many countries for adults and adolescents (and in some countries also for children 4 or 6 years of age and older) who have moderate to severe asthma. You may hear this referred to as MART or SMART therapy, which stands for Single Maintenance and Reliever Therapy. With this treatment, you use the same anti-inflammatory reliever inhaler for relieving symptoms (and before exercise if needed) and for your regular daily preventer or controller treatment.

Make sure that you learn the correct way to use your inhaler or inhalers. For example, if you have a “puffer” that contains an aerosol to deliver the medication to your airways, you should breathe in the medication slowly. If you have a dry powder inhaler, you should breathe in the medication strongly. 

Depending on your symptoms, other medications and treatments may also be prescribed. Complementary therapies [28], such as special breathing exercises, may be recommended to help you learn to breathe better with asthma and increase your overall lung capacity, strength and health. It is essential for you to avoid exposure to tobacco smoke or vape products, because these cause serious lung problems in people with asthma. If you smoke or vape, ask your doctor or pharmacist for advice to help you quit. Where possible, avoid indoor and outdoor air pollution. For example, if possible, exercise away from main roads. Regular physical exercise and a healthy diet are recommended for all people with asthma. 

Content Reviewed by GAAPP’s Scientific and Advisory Panel.

Living Better with Asthma


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