What is asthma?
Asthma is a chronic respiratory disease which causes inflammation and swelling of the airways. During an asthma attack, the airways narrow, which leads to difficulty breathing. The characteristic wheezing in an asthma attack is the result of air being forced through the narrow space. Asthma can affect both children and adults, though it’s more common in children. Attacks can range from mild to severe, and even result in death. An estimated 235 million people worldwide are affected by asthma.
In Singapore, asthma affects approximately 5% of adults and 20% of children. According to the Global Initiative for Asthma's (GINA) Global Burden of Disease Report, Singapore is a high-risk country for asthma deaths – out of all the asthma patients admitted into ICU, 67% had untreated asthma. Of these, none were using preventive medication. Many also did not receive regular medical reviews for asthma, and were relying heavily on oral medication and reliever inhalers such as Salbutamol for acute attacks.
What triggers asthma attacks?
Asthma can be triggered by both physical and emotional triggers including but not limited to:
- Allergens such as dust mites in household fabrics such as bedding, carpets and stuffed toys, animal fur, tobacco smoke, pollen, mould, chemical fumes, and air pollution.
- Cold air, physical exertion or exercise.
- Emotions such as fear or anger.
- Certain types of food and medication.
Why is it important for asthma to be treated?
The goal of asthma treatment is to reduce the frequency and severity of attacks, thereby improving quality of life. If left untreated, asthma can disrupt rest, daily life, work or school, and other activities – this is sometimes referred to as the burden of asthma. In severe cases, asthma can be fatal.
How is asthma treated?
While asthma cannot be cured, it can be managed well with medication and by avoiding known triggers. A chronic condition, asthma requires long-term treatment known as preventor or controller medication that must be taken daily. Doctors normally prescribe inhaled corticosteroids to reduce inflammation in combination with long-acting beta2-agonists to reduce the frequency and severity of asthma attacks over the long term.
Reliever or ‘rescue medications’ known as short-acting beta2-agonists can provide immediate relief in the event of an asthma attack. However, the latest guidelines from GINA recommend that low dose inhaled corticosteroids should be taken concurrently whenever a reliever inhaler is used, and that patients use inhalers that contain low dose inhaled corticosteroids.
Alternatively, specific combination inhalers may be used as a reliever during acute asthma attack. However, please consult your doctor before doing so. While there are both inhaled and oral medications, inhalers are often recommended as they deliver the medication directly to the lungs.
Are people with asthma more likely to get sick from other diseases?
Those with asthma should take the necessary steps to manage it well as poorly-controlled asthma can place them at increased risk for other respiratory conditions.
- Chronic obstructive pulmonary disease or COPD refers to a group of lung diseases, including emphysema and chronic bronchitis. It is a leading cause of death around the world, as it causes permanent lung damage that makes it difficult to breathe.
Smoking significantly increases the risk of developing COPD, and a study found that people with asthma are 12.5 times more likely to be diagnosed with COPD. However, those who were no longer experiencing symptoms faced no additional risk, emphasising the importance of good asthma control. Another recent study named COPD as the greatest risk factor for severe COVID-19 among hospitalised patients.
- COVID-19 infects the respiratory tract, comprising the nose, throat, and lungs, which could cause an asthma attack. People with pre-existing chronic respiratory conditions like asthma are more vulnerable to adverse outcomes from the virus, such as pneumonia and more likely to experience more severe illness or hospitalisation from contracting COVID-19. Experts urge that it is important to continue with existing controller medications to prevent asthma attacks, thereby reducing the need to seek medical attention and the risk of being exposed to COVID-19.
- Influenza or flu, which attacks the nose, throat and lungs, can also trigger asthma symptoms or attacks. As people with asthma are also more likely to experience severe complications from the flu, it is recommended to protect against infection with an annual flu vaccine.
- Lung cancer, usually associated with smoking, has a proven association with asthma. Several studies have found that people asthma have an increased risk for developing lung cancer. This is regardless of gender, race (both Caucasians and Asians), and whether one smokes.
- Pneumonia, a lung infection caused by bacteria, fungi, parasites or viruses, can affect one or both lungs. This can cause symptoms that appear similar to asthma. While there is no direct cause, those with asthma face a higher risk of developing . Research has also found that a bout of pneumonia can lead to more frequent asthma-related hospital visits.
How can I manage my asthma more effectively?
It is recommended that patients consult with a respiratory physician to understand one’s condition better, especially to understand its severity, and to receive appropriate medical advice for long-term treatment and management. It’s important to follow the recommended plan in order to achieve the desired goal of reducing the frequency and severity of asthma attacks. In the meantime, any episodes of breathing difficulty should be regarded for emergency treatment.
Article reviewed by Dr John Law, respiratory physician at Gleneagles Hospital
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