Asthma

Asthma is a common respiratory condition which affects the air passages or breathing tubes that carry air in and out of your lungs. Asthma causes wheeze and cough, and can make breathing difficult. New Zealand has one of the highest rates of asthma in the world, affecting up to 1 in 4 children and 1 in 6 adults.

Learning about asthma, what causes it and how it is treated can help you avoid triggers and keep your symptoms under control.

Key points:

  1. If you have asthma, your airways are very sensitive and react to certain triggers such as allergens (substances that cause an allergic reaction), viruses, cold or humid weather, exercise and air pollutants such as cigarette smoke.
  2. These triggers cause your air passages to tighten up, swell on the inside (become inflammed) and produce more mucus.
  3. As a result, the airways become narrower, making it difficult for air to move into the lungs, and even more difficult for air to move out. 
  4. Avoiding your triggers and knowing what to do when you have asthma is key to managing your asthma well. 
  5. Seek urgent medical help if you have severe asthma symptoms.

What causes asthma?

Asthma is thought to be caused by a combination of genetic and environmental factors.

Genetic factors

Asthma and allergies are closely linked. About 70 to 80% of asthma in New Zealand is associated with allergies. Often people with asthma also have eczema or hay fever, or have close family members who have asthma, eczema or hay fever.

  • The tendency for these three condition to occur together is known as 'atopy'. 
  • If you are atopic, allergies, especially to dust mite, can be a trigger for your asthma. 

Environmental factors

Factors in our environment thought to have a role in causing asthma include:

  • allergens air pollution (such as second hand smoke)
  • environmental chemicals.  

Triggers – things that can cause asthma symptoms

Learning what triggers your asthma and finding ways to avoid or reduce the impact is an important part of managing your asthma. 

Common asthma triggers include:

  • house dust mite
  • infections of the airways such as colds and flu 
  • pollen or mould
  • pets
  • cigarette smoke
  • weather such as change in temperature, cold weather or humid weather
  • exercise
  • stress and high emotion
  • chemicals that irritate the airways such as sprays, perfumes, cleaning fluids
  • some medications.

What are the symptoms of asthma?

Common symptoms of asthma include:

  • difficulty breathing, feeling out of breath, can't get enough air out of the lungs
  • a tight feeling in your chest like something is squeezing or sitting on your chest
  • wheezing (a whistling, musical or squeaky noise in the chest)
  • a cough which can be worse at night or in the morning.

If you have any of these symptoms, see your doctor so they can assess if this is due to asthma or something else. 

Severe asthma symptoms

From time to time, your symptoms may get gradually or suddenly worse. Seek urgent medical help if you have any of these severe symptoms:

  • it is difficult to talk
  • your lips and/or fingernails have a bluish tinge
  • your nostrils flare when you breathe
  • the skin around your neck and/or ribs pulls in when you breathe
  • your heart is racing
  • it is hard to walk.

For severe asthma symptoms, you should use your reliever inhaler immediately and call an ambulance 111 or go to your nearest Accident & Emergency clinic.

How is asthma diagnosed?

In most cases, asthma can be diagnosed from:

  • your history (describing your asthma symptoms now and in the past)
  • listening to your breathing with a stethoscope
  • checking how your lungs are working with a device called a peak flow meter.

In some cases, more detailed testing may be required, such as a spirometry (lung function) test, a skin-prick test to test for allergens or rarely, a chest x-ray to rule out other conditions.

Once a diagnosis is made, your doctor will prescribe the type of medicines you need to take and will also set up an asthma action plan. This plan will remind you how to manage your asthma on a daily basis and how to recognise and handle worsening symptoms.

Asthma is ongoing and your symptoms may come and go. In some children, the symptoms may disappear as they get older.

How is asthma treated?

While asthma cannot be cured, the correct use of medication combined with other self-care measures means that symptoms can be well controlled in most people.

The main aims of asthma treatment are to:

  • keep symptoms under control
  • prevent 'asthma attacks' or 'exacerbations' (sudden worsening of symptoms)
  • keep lungs healthy as possible
  • stop asthma from interfering with school or work
  • help you enjoy a full and active life. 

There are many different types of asthma medicines and sometimes you will have to take more than one. These are usually puffers or inhalers but may also be tablets. They fall into the main categories of:

The main groups of asthma medicines are:

  • symptom relievers
    • These provide short-term relief by relaxing the muscles around your airways, and open up your airways and makes it easier to breathe.
    • Common relievers include salbutamol and terbutaline.
  • asthma preventers 
    • These are taken every day to prevent symptoms from developing.
    • They do not provide quick relief of asthma symptoms.
    • The two main types of preventers commonly used are:
      • steroid preventers
      • long-acting bronchodilator preventers.
  • prednisone (steroid tablets)
    • These are usually taken for very severe episodes of asthma and works more intensely to reverse the swelling of the airways. 

Read more about asthma medications.

  • Keep an eye on your symptoms. If you are getting wheezy more than two times a week, it may mean your asthma is not well controlled. See your doctor for a check up.
  • If you have symptoms of allergic rhinitis (such as nasal congestion, hayfever, runny nose) talk to your doctor about medication to treat these symptoms such as antihistamines or nasal steroids (steroid nasal sprays).  Treating allergic rhinitis can improve your asthma symptoms. 

Self care

There are many things you can do to improve how well your asthma is controlled. By working with your doctor or nurse to create an asthma action plan, you can reduce the severity of your asthma symptoms and how often they occur.

Here's what you can do:

  • Understand your asthma, recognise your symptoms and your triggers.
  • Take your prescribed medication – especially your preventer – every day.
  • Don't smoke and keep clear of anyone else who smokes and of any other fumes.
  • See an allergy specialist about managing allergies if these are a known trigger for you.
  • Use the Asthma under control test to check if your asthma is well controlled or not.
  • Complete an asthma self-management action plan.
  • Use a peak flow meter to take and record regular readings.
  • Keep active – physical activity improves how well your lungs work, and people who are fit usually find they have less asthma and cope better when they do have it. 
  • Visit your asthma team (your GP, your practice nurse and your pharmacist) regularly. They will review the medications you are taking and can teach you how to use your inhaler properly, for maximum benefit. 
  • Get a seasonal flu jab – see your doctor about a free flu vaccination each autumn to reduce your risk of flu, which in turn will reduce the risk of serious asthma.
  • Keep your dust mite allergy under control.

Read more about an asthma action plan.

Learn more

Living with asthma Asthma & Respiratory Foundation NZ
Breathe Better September Asthma & Respiratory Foundation NZ
Family health history Genetic Science Learning Centre, University of Utah, USA, 2015
Rhinitis and Asthma: "Combined Allergic Rhinitis and Asthma Syndrome" World Allergy Organization

Credits: Editorial team. Last reviewed: 29 Jul 2016