World Asthma Day is an annual initiative organised by the Global Initiative for Asthma (GINA) every May to raise awareness of this chronic respiratory condition globally.
This year (2023), it has chosen “Asthma Care for All” as its theme, in an effort to encourage healthcare leaders to ensure availability of, and access to, effective, quality- assured medications.
This is especially pertinent in low- and middle-income countries, where the majority of the burden of asthma illness and death occur.
It starts with inflammation
Asthma is a chronic inflammatory condition affecting the airways of the lungs.
As a consequence of the inflammation, the airways become more narrowed and sensitive.
This can lead to symptoms typically associated with asthma, such as coughing, chest tightness, difficulty breathing and wheezing.
It is believed that asthma is caused by a combination of genetic predisposition and environmental factors.
Triggers tend to vary from person to person.
Some of these are external, such as cigarette smoke, viral infections, a change in weather, dust mites, pollen and animal dander.
Others are internal, such as a post-nasal drip, heartburn, stress and exercise.
Over the past few weeks, increasing numbers of patients with asthma have noticed that their symptoms have worsened as a consequence of exposure to haze.
Health risks of haze
We have been witnessing the return of haze, a situation whereby dust, smoke and other dry particles obscure the visibility of the air.
It is a form of air pollution, which is estimated to kill nine million people globally every year.
The haze is a seasonal phenomenon that affects many countries in South-East Asia.
It is usually precipitated by fires from slash-and-burn farming methods – a cheap and easy way of getting rid of plants in farming fields to create space for new crops.
These emissions contain particulate matter (PM) that can be carried across countries, many of which are less than 2.5 microns in size (known as PM2.5).
PM2.5 is not only easily carried, but also easily penetrates our airways given its tiny size.
In the short term, it can trigger asthma attacks, alongside exacerbations of other lung-related diseases such as chronic obstructive pulmonary disease (COPD) and pulmonary fibrosis.
The particles and pollutants in haze do this by irritating the airways and causing increased inflammation.
This not only triggers asthma symptoms, but also increases the risk of an asthma attack.
The severity of an attack is dependent on a number of factors.
These include how well-controlled the underlying asthma is, the level and length of exposure to haze, and the concentration of pollutants in the air.
Some studies have established a link between higher levels of Air Pollutant Index (API) and respiratory symptoms.
Risks are especially high for those of extreme ages (both the young and the old), those working outdoors, and those with multiple comorbidities (illnesses).
A study published in 2005 in the International Journal of Hygiene and Environmental Health highlighted increases in hospital admissions for those with underlying lung disease, with elderly patients above 65 years of age being the most vulnerable.
A 1998 study looking at schoolchildren in Malaysia showed significant reduction in lung function during haze episodes, in comparison to pre-exposure conditions, especially in girls.
When lung function testing was repeated again after the haze episode, there was only partial recovery.
This suggests possible long-term health implications from persistent residual effects, or at least a significant recovery period associated with each haze episode.
Children who were exposed to air pollution, even in the womb, are at risk of developing asthma, cough, and even lung cancer, when they are older.
Controlling the condition
Asthma symptoms can be alleviated in the short term by reliever medications, but in the long run, controller or preventer medications need to be taken regularly for good control. — Fotolia
Although asthma has no cure, the vast majority of cases can be well-controlled, with the aim being for patients to have a normal, symptom-free life.
Medication in the form of inhalers help control asthma symptoms by reducing airway inflammation and preventing airway narrowing (thus reducing symptoms).
Inhalers are generally divided into two categories:
> Reliever
A reliever (usually in the form of a type of medicine known as a beta-agonist) works quickly to open up airways during an asthma attack.
It relaxes the muscles around the airways, making it easier to breathe.
Its effect only lasts a short while, and the need for recurrent use is an indicator that the underlying asthma is not well-controlled.
> Controller/Preventer
A controller or preventer inhaler is used every day to keep asthma symptoms at bay.
It usually contains inhaled steroids, which reduce inflammation of the airways, and therefore, makes it less sensitive to triggers.
It is worth noting that inhaled steroids are very safe and do not have the same risk profile as the regular use of steroid tablets or injections.
In fact, it is the cornerstone of asthma treatment, and is even used in children and pregnant women who have poorly-controlled asthma.
In a small but significant number of people, more personalised biologic medications may be necessary to keep their asthma under control.
Keeping it under control
Keeping asthma under control involves both the appropriate and regular use of medication, as well as taking the necessary measures to reduce exposure to triggers.
In the case of haze, it is important for those with asthma to monitor air quality and limit their exposure to pollutants.
This may involve staying indoors during periods of high haze or wearing a face mask designed to filter out small particles when outside.
It’s also important to follow the individualised asthma management plan prescribed by a healthcare provider, which may include medication, inhalers and other treatments to help manage asthma symptoms.
Conditions like asthma are likely to increase over time given the increasing planetary stress from pollution and human activities.
At the policy level, the government should ensure that those who need appropriate asthma medication have access to them, while also executing the necessary internal and inter-governmental policies to protect us from air pollution.
Dr Helmy Haja Mydin is a consultant respiratory specialist and a Special Advisor to the Health Minister. For further information, email [email protected]. The information provided is for educational and communication purposes only. The Star does not give any warranty on accuracy, completeness, functionality, usefulness or other assurances as to the content appearing in this column. The Star disclaims all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.
