Asthma is a reversible narrowing of the airways in the lungs. It is characterised by 3 airway problems, reversible obstruction, caused by increased reaction of the airways to various stimuli (triggers) and inflammation. It can be life-threatening if not properly managed
Can I get asthma in adulthood?
Yes. Asthma can develop at any age, though it is more common in children and teenagers. Some people get asthma for the first time when they are older. More than 13 million people have asthma and 1.5 million of them are 65 years or older.
Is asthma inherited?
Yes, there is a tendency for asthma to be inherited, such that asthma may seem to "run in the family". If you have a blood relative with asthma or allergies, you are at higher risk of getting asthma.
The most common symptoms are:
- Wheezing sound
- Cough particularly at night
- Difficulty in breathing
- Chest tightness
Causes and Risks
There are many different factors that can trigger an asthma attack. These may be found indoors and outdoors and include:
- Changes in temperature and weather
- Tobacco smoke and wood smoke
- Perfume, paint and any strong odors or fumes
- Allergens (particles that cause allergies) like dust mites, pollen, molds and animal dander
- Infections (viral or bacterial) including common cold and influenza
- Certain medications eg. aspirin
Atopy and Asthma
Atopy is a genetic tendency to develop allergic disease. This is usually manifested in the skin by a rash (eczema or hives). Other manifestations are allergic rhinitis and asthma.
The test for asthma involves a breathing test (known as spirometry) which may be done before and after administration of a bronchodilator to determine if there is reversible obstruction of the airways. In addition, a substance known as methacholine (known to induce airway narrowing), may be used to determine if the airways are hyperresponsive (typical of asthmatics). These tests are available in most major restructured hospitals.
Asthma is a treatable health condition. Although at present there is no cure, with good management, people with asthma can lead normal, active lives.
There are 4 main components to the treatment of asthma:
- To assess the severity of asthma and to monitor the response to treatment using objective tests of lung function (for example spirometry and peak expiratory flow rate)
- The use of medication to reverse and prevent airway inflammation that contributes to the airway narrowing
- To take preventive measures to avoid or eliminate factors that induce or trigger asthma flare-ups
- Patient education
Medications used in the treatment of asthma
Preventers/Anti-inflammatory agents control airway inflammation thereby keeping the airways open by reducing the swelling and mucus. Inhaled steroids are the most effective anti-inflammatory medication for the treatment of asthma. They should be taken daily to reduce the risk of asthma attack and to prevent airway injury. It may take a few months for preventers to reach their optimal effect. Examples of inhaled steroids include beclomethasone, budesonide and fluticasone.
Relievers/Bronchodilators work mainly by relaxing the airway muscles to open the airway. They provide relief from asthma symptoms within minutes and are used during an acute asthma attack. They have little or no effect on airway inflammation. Examples of bronchodilators include beta-agonists (eg salbutamol) and anti-cholinergics (eg ipatropium).
Frequently Asked Questions
Can people with asthma exercise?
Yes. People with asthma should not avoid exercise as it is beneficial. Swimming is often recommended when asthma is under control. Most asthmatics can participate and excel at any sport (a number of Olympic medalists have asthma). For people whose asthma is brought on specifically by exercise, medication can be taken before exercise to help avoid an episode.
What is exercise-induced asthma?
This is narrowing of the airways that is caused by exercise. It is more likely to happen when there is exposure to cold air with low humidity, and air pollutants. A specialised test that includes cycling or treadmill running is usually performed to confirm the diagnosis.
What is a peak flow meter?
It is a simple device which measures airflow and therefore determines how open your airways are objectively (rather than by guessing). It is analogous to a thermometer for a patient with fever. It is used to determine the severity of an attack, to monitor response to treatment and to detect worsening in lung function in a patient who has difficulty recognizing symptoms of asthma thereby enabling prompt treatment to avoid a possible serious attack.
What is the relationship between asthma and smoking?
Smoking has a harmful effect on the airways and can trigger an asthma attack. All asthmatics should not smoke, and should also avoid passively inhaling smoke from cigarettes, cigars and pipes from family members.
What happens when an asthmatic gets pregnant?
About a third of asthmatics worsen during pregnancy. Uncontrolled asthma causes a reduction in oxygen content in the mother's blood. Since the fetus gets its oxygen from the mother’s blood, this may lead to impaired fetal growth and survival. Properly controlled asthma does not increase the risk of maternal or infant complications and is essential during pregnancy.
American Academy of Allergy, Asthma and Immunology: http://www.aaaai.org
American Lung Association: http://www.lungusa.org