Asthma is a long-term condition that affects the airways in the lungs, making it hard for you to breathe. Symptoms include coughing, wheezing and shortness of breath.
Nearly 600,000 people in New Zealand use asthma medication, including one in seven children and one in eight adults. Asthma is one of the most common causes of admission to hospital for children. On average, 77 New Zealanders die from asthma each year.
Asthma can start at any age but commonly begins in childhood. Many children grow out of asthma by their teens. Others first develop asthma in adulthood.
New Zealand, along with countries like Australia and Great Britain, has one of the highest rates of asthma in the world. It particularly affects Maori and Pacific peoples. Exposure to certain dusts or chemicals may predispose people in some lines of work to asthma.
Signs and symptoms
With asthma, the airways in the lungs are sensitive to certain irritants or triggers. When exposed to these irritants the small airways in the lungs become swollen, muscles surrounding the airway walls tighten and mucous is produced inside the airways. This makes breathing difficult and produces the cough, wheeze and shortness of breath that are typical asthma symptoms.
The severity of asthma symptoms varies between individuals. Some experience only mild symptoms while others may have severe attacks that happen suddenly. A severe asthma attack can be life threatening if treatment is not sought immediately.
Common signs and symptoms of asthma include:
- Coughing – which may worsen at night
- Chest tightness
- Shortness of breath
- Difficulty speaking (in more severe attacks)
- Blueness around the mouth (in more severe attacks).
The exact cause of asthma is not fully understood. It is believed to be caused by a combination of genetic (inherited) and environmental factors. It may be related to modern living, including environmental changes, diet or exposure to some infections.
It is known that most people with asthma constantly have some degree of inflammation in their airways. Their airways are also sensitive to certain irritants, known as triggers. Triggers can cause tightening of already inflamed airways, provoking an asthma attack. Each individual tends to have different asthma triggers, including one or more of the following:
- Pollens or moulds
- House dust mites
- Air pollution
- Certain foods or food additives
- Strong perfumes
- Cigarette smoke
- Some medicines eg: aspirin, non-steroidal anti-inflammatory drugs, beta blockers
- Respiratory infections such as colds and influenza
- Changes in temperature and humidity (eg: sudden exposure to cold dry air)
- Psychological influences eg: extremes of emotion
- Workplace irritants eg: paint and varnish fumes, flour, wood dust.
If asthma is suspected, your doctor will discuss your symptoms and ask you about any family history of asthma. Tests the doctor may use include chest x-rays and measuring how quickly you can exhale air using a peak flow meter.
Asthma symptoms and signs vary through the day and through the week. Peak flow meter tests twice daily for a week, or before and after using a reliever inhaler, will show this variation. The peak flow rate may vary by more than 20% in asthma sufferers.
Sometimes specialised challenge tests may be useful. These tests use a chemical to try to provoke a brief episode of asthma which can be measured. This can confirm a diagnosis and give an indication of how severe the condition is.
Collection of phlegm or measurement of nitric oxide may be used to follow the progress of more complex asthma.
Specialist referral should be considered if there is uncertainty about the diagnosis, when the response to initial treatment is not what was expected, or when an occupational cause of asthma is possible.
While asthma cannot be cured, it can be controlled by avoiding triggers and using medications. A doctor will be able to discuss whattype of medications may be most appropriate for you.
It is important for someone with asthma to understand how their asthma medication and asthma inhalers work. Inhalers are devices that allow asthma medication to be delivered directly to the lungs, either as an aerosol or as a powder. Note: Using corticosteroid inhalers for asthma can trigger oral thrush infections - drinking or rinsing with water after using your inhaler may help prevent this from happening.
The main types of medications used to control asthma are:
These are usually an inhaled corticosteroid medication that has the effect of reducing swelling and decreasing the body’s reaction to triggers . It takes time for preventers to start working (up to three months of regular use). They are taken on a regular basis each day to prevent symptoms. Examples of preventers are fluticasone (Flixotide), budesonide (Pulmicort) and beclomethasone (Beclazone).
These inhaled medications cause the airways’ muscle to relax, helping to open up the airways. They are often referred to as bronchodilators. The are quick acting and are used to relieve symptoms once they have started. Examples of short-acting relievers are terbutaline (Bricanyl) and salbutamol (Ventolin).
These are long-acting inhaled relievers and are used in conjunction with a preventer. They work by keeping the airway muscles relaxed and are usually used twice a day. The use of a symptom controller should reduce the need to use a short acting reliever. Examples of symptom controllers are formoterol (e.g. Foradil) and salmeterol (e.g. Serevent).
Combination inhalers contain both preventer and symptom controller medicine in one device. Examples of combination inhalers are fluticasone and salmeterol (Seretide) and budesonide and formoterol (Symbicort).
For people whose asthma is triggered or made worse by allergies, immunotherapy or a drug called omalizumab may be beneficial. Immunotherapy involves receiving repeated allergy shots over several years to gradually reduce the body’s immune response to specific allergens. Omalizumab (Xolair) is given by injection every two to four weeks and acts by modifying the immune system.
Worsening or severe asthma:
Increased frequency and/or severity of asthma symptoms may require a change in the treatment regimen or an increase in the amount of medication taken. A course of corticosteroid medication (e.g. prednisone) injected into a blood vein or in tablet form, may be prescribed until symptoms are controlled. Severe asthma attacks may require hospitalisation to control symptoms. Relieving medication may need to be given using a nebuliser (inhaled in a fine mist of oxygen via a specialised mask or mouthpiece) or intravenously (as an infusion into a drip in the hand or arm).
Management of asthma
Quit smoking and encourage family members, or others who may expose you to their second-hand smoke, to quit as well.
Learning to avoid triggers can help reduce symptoms and the frequency of asthma attacks. Be aware of symptoms and take appropriate medication to ease these. This may involve increasing asthma medication. Regular use of a peak flow meter and recording of those measurements can indicate how well controlled asthma is and indicate worsening of the condition.
Having a self management or action plan is also an important tool in the management of asthma. This is a written guideline of what to do when asthma worsens. It is usually individually formulated in conjunction with a doctor or asthma nurse specialist.
Getting a seasonal influenza vaccination ("flu jab") will reduce the risk of influenza, which in turn will reduce the risk of serious asthma. People who are on regular preventive therapy for asthma (as well as people with various other medical conditions) can see their doctor about a free influenza vaccination each autumn.
Other control methods include breathing techniques such as the Buteyko Method. Staying physically fit and not smoking can also minimise asthma symptoms and attacks.
Be alert for signs of worsening asthma: night waking, breathlessness or difficulty speaking on exertion, loss of response to your reliever.
For more information about asthma talk to your doctor or contact support and resource groups such as:
Asthma and Respiratory Foundation NZ
Asthma New Zealand
Advocacy & Education Committee of the Asthma Foundation (2013). What is asthma? (Booklet PDF). Wellington: Asthma and Respiratory Foundation of New Zealand. https://s3-ap-southeast-2.amazonaws.com/assets.asthmafoundation.org.nz/documents/What-is-Asthma-Resource.pdf
Advocacy & Education Committee of the Asthma and Respiratory Foundation (2013). Triggers in asthma (Booklet PDF). Wellington: Asthma and Respiratory Foundation of New Zealand. https://s3-ap-southeast-2.amazonaws.com/assets.asthmafoundation.org.nz/documents/Triggers-in-Asthma-Resource.pdf
Asthma and Respiratory Foundation NZ (Year not specified). Living with asthma (Web Page). Wellington: Asthma and Respiratory Foundation NZ. https://s3-ap-southeast-2.amazonaws.com/assets.asthmafoundation.org.nz/documents/What-is-Asthma-Resource.pdf [Accessed: 17/01/20]
Asthma and Respiratory Foundation of New Zealand (2014). Key statistics: Respiratory disease in New Zealand (Web Page). Wellington: Asthma and Respiratory Foundation NZ. https://www.asthmafoundation.org.nz/research/key-statistics [Accessed: 12/05/17]
Barnard, L.T., Zhang, J (2018). The impact of respiratory disease in New Zealand: 2018 update (Report PDF). Wellington: Asthma and Respiratory Foundation NZ. https://s3-ap-southeast-2.amazonaws.com/assets.asthmafoundation.org.nz/images/NZ-Impact-Report-2018_FINAL.pdf
Ministry of Health (2014). Asthma (Web Page). Wellington: Ministry of Health. http://www.health.govt.nz/your-health/conditions-and-treatments/diseases-and-illnesses/asthma [Accessed: 17/01/20]
O’Toole, M.T. (Ed.) (2017). Asthma. Mosby’s Dictionary of Medicine, Nursing & Health Professions (10th ed.). St Louis, MI: Elsevier.
Last Reviewed – February 2020
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