Common Conditions

Asthma – What You Should Know

1. What exactly is Asthma ?

Asthma refers to airways (breathing tubes) that are chronically sensitive and inflamed. Inflammation (redness and swelling) is the basis and this result in airways that are hypersensitive to trigger factors such as dusts, smog, the haze, certain foods (particularly the preservatives and artificial colourings used in food preparations), some pets etc.

When the airways react with these trigger factors, they can result in asthmatic symptoms, which can be sometimes dramatic and severe.

It is important to understand that Asthma is usually part of a spectrum of clinical disorders which is commonly termed “Atopic Tendencies”. Besides sensitive lower airways, many patients would suffer from sensitive upper airways (Allergic Rhinitis), skin (Atopic Dermatitis), eyes (Allergic Conjunctivitis) too.

2. What happens during an Asthma Attack ?

During an attack of asthma, the airway muscles constract, thereby narrowing the airways quickly. The airways also become even more inflamed. As a result of increased inflammation, there will be more swelling, narrowing the airways further. Inflammation also causes the airways to produce thick sticky phlegm, which might clog the airways.

3. What symptoms does an asthmatic experience during an attack ?

During an attack, the commonest symptoms is that of cough associated with a sensation of difficulty in breathing (dyspnoea). The cough is sometimes the only presenting symptom, and is usually worse in the night or early mornings. Coughs can be productive of thick sticky phlegm. However, many times, the cough is non-productive.

The sensation of dyspnoea is usually described as chest tightness, and can be rather dramatic. Some sufferers had akin the sensation to taking each breath through a straw. The sufferer can be very anxious at this stage and panic. Sometimes, they hyperventilate during this time. Dyspnoea is usually less pronounced when the sufferer stand or sit. It is more pronounced when he lies down.

The sufferer will also note that he/she is extremely tired and will not be able to carry on with his/her usual task without feeling breathless.

Wheezing is the other common clinical symptom of asthma. This is a musical noise when air is drawn through markedly narrowed airways. This is usually more pronounced during expiration (breathing out).

As asthma is part of a spectrum of disease known as Atopic Tendencies, the patient may also complain of upper airway symptoms such as rhinorrhoea (running nose) and blocked nose in the mornings and when exposed to dusts.

In the child, asthmatic symptoms often comes in the form of nocturnal coughs (coughing at night during sleep), breathlessness especially when the child is noted to breathe laboriously using accessory muscles, listlessness and poor appetite.

4. What are the trigger factors to asthmatic attacks ?

The condition of asthma is basically an interaction of constitutionally sensitive airways with the environment. It is therefore important to understand that trigger factors precipitate attacks of asthma, but is not causative.

Many things and circumstances in the sufferer’s environment can thus be trigger factors. Common trigger factors include dusts, house dust mites in bedding and draperies, pollution, strong odours/sprays, pests/insects such as cockcroaches, animal dander, tobacco smoke, pollens, viral and bacterial infections of the respiratory tract, certain medicines and even exercise.

Exercise ironically can precipitate an asthmatic attack. This phenomenon is known as EIA (Exercise Induced Asthma). EIA commonly occurs with children and young adults, and is related largely to hyperreactive airways as a result of poorly controlled asthma.

Exercise in asthmatics is thus confusing to laypersons. Suffice to state that exercise is an integral part of asthma management, once the condition is under good control. This will be elaborated below.

5. Should one be concerned if diagnosed to be suffer from asthma ?

It is important to realize that asthma is a treatable condition. The condition can be well controlled and the “sufferer” can lead NORMAL lives. Unlike other conditions like Diabetes Mellitus and Hypertension, asthmatic medicines can usually be reduced in dose and frequency when good control is achieved.

If asthma is left uncontrolled on the other hand, the consequences can sometimes be disastrous. Asthma, though highly treatable, is known to cause unnecessary deaths.

It is important to control the condition as early as possible. It has now been shown in many studies that if left uncontrolled, asthma can result in permanent damage to the airways (Airway Remodeling). The result is reduction in the lung function for life.

6. How can asthma be treated and managed ?

As mentioned previously, it is important to manage the sufferer in total, understanding that asthma is often part of a syndrome of conditions called Atopic Tendencies. The sufferer will also need to do some form of management of his/her environment to try to minimize trigger factors to asthmatic attacks.

With proper medicines and avoidance of trigger factors, asthma can be fully controlled. The sufferer can lead a normal healthy lifestyle.

7. What are the types of medicines available for treating asthma ?

In general, asthma medicines are divided into 2 main groups – Relievers and Controllers.

Relievers

As the term suggests, Relievers are medicines that relieve the symptoms of asthma. However, it is important to note that these medicines does not treat the underlying cause of the disease. Relievers are usually bronchodilators (medicines used to open up the constricted airways), thereby alleviating symptoms such as coughs, chest tightness, breathlessness and wheeze.

Relievers include short acting bronchodilators such as Salbutamol (available as Ventolin, Respolin), Terbutaline (available as Bricanyl), Ipatropium Bromide and fenoterol hydrochloride combinations (available as Berodual), Ipatropium and Salbutamol combinations (available as Combivent).

Formeterol (Usually available in combination with Budesonide as Symbicort) is a long acting reliever of asthmatic medicines.

Theophyllines in the form of Nuelin has also been used to relax the airways and thus relieve symptoms. However, these medicines are available in the tablet and injectable forms. This means that the medicine will have to travel the system, and thus will be potentially be associated with more side effects.

Controllers

As the term suggests, these medicines targets the inflammatory process that is the cause of asthma. They thus keep the airways stable and thus prevent asthmatic symptoms even when exposed to trigger factors.

Controllers should thus be taken on a regular basis to keep the airways in good condition. Most controllers are steroids, usually administered directly to the airways by various types of delivery devices. Because the medicines are directly delivered to the airways, only very small doses are used, and thus they are extremely safe to use.

Examples of controllers are Beclomethasone dipropionate (available as Becotide), Fluticasone propionate (in preparations such as Flixotide and Seretide), Budesonide (in preparations such as Pulmicort and Symbicort).

Severe asthmatic symptoms may require the use of systemic steroids in the form of Prednisolone, Dexametasone or even Intravenous Hydrocortisone.

Over the last decade, Leukotriene antagonists have been found useful as controller, Singulair, is available as tablets or powdered sachets for oral consumption. These medicines have relatively minimal side effects and have been approved for use by very young children as well. The other advantage of Leukotriene Antagonists is that they also work well with Allergic Rhinitis, an upper airway problem found commonly with asthmatic sufferers.

Combination Reliever and Controller inhalers

Recently a major change in asthma treatment is to put both reliever and controller medication in the same inhaler.  This has been shown to be an important advancement in the treatment of asthma.  They can be use 2 times a day as in Symbicort, Seretide, Flutiform or Foster or once a day as in Relvar.

Biologic Therapy drugs

In severe eosinophilic asthma where control cannot be achieved by relievers, controllers and combination relievers and controllers or even oral steroid, biologics in the form of monoclonal antibodies (Nucala an Fasenra) can be given as injections to improve asthma and reduce the usage of oral steroid.

8. Medication Delivery Devices

The inhaler is the preferred route of delivering asthmatic medicines. This is because it is direct, and faster in action compared to oral medicines. It has the added advantage of delivering lower doses of the medicines too, and hence is associated with minimal systemic side effects.

There are many inhalational devices available.

The Metered-Dose Inhaler (MDI) is the commonest of these devices. This is a small hand-activated device that quickly delivers a specific amount of medication into the lungs when inhaled through the mouth. This will require good hand-breath coordination, which is sometimes difficult particularly amongst the elderly and the very young.

MDI can be used in conjunction with spacer devices such at the Volumatic and the Aerochamber for more efficient delivery.

Asthma medicines are also available in the powdered form, for example Seretide and Symbicort. They are delivered via breath actuated devices that is much easier to use than the MDIs. Such devices include the Acuhaler and the Turbuhaler.

Medicines to be delivered to the airways can also be achieved usually a Nebuliser. This dispense medication in a mist that can be breathed in through a mask. Nebulisers are usually used in emergencies or for a severe asthmatic attack. The dose of medicines delivered by this method is usually higher than the MDI or the Breath Actuated Devices. The asthmatic sufferer will then be able to experience the side effects of medicines more acutely.

9. Exercise and Asthma

This is a confusing subject, as sufferers might get different advices depending on the circumstances. Asthmatic sufferers are generally advised not to exercise if the condition is not under control and during exacerbations. Exercise can then be a trigger factor during these times.

However, it is important to realize that asthmatic sufferers should be allowed to lead as normal a lifestyle as possible, and that includes physical activities that the person enjoys. In fact there are the advantage of improving lung function with certain exercises, which will thus set the threshold of an asthmatic attack much higher. Such exercises generally involve activities which strengthen respiratory muscles, such as swimming. Exercise also brings about certain hormones that actually reduce airway inflammation. It is therefore not unusual to know of asthmatic sufferers who need much less medications after they have embarked on a regular exercise program.

10. Asthma and Pregnancy

This is also another subject of concern, as pregnant mothers are very worried about medicines affecting the growth or cause abnormalities in the unborn fetus. While this fear is not irrational, it is important to understand that good control of the airways is preferred in pregnant asthmatic sufferers. This would eventually ensure normal growth of the fetus, an uneventful pregnancy and childbirth.

Medicines currently available for treatment of asthma is safe during pregnancy, and should thus be continued as prescribed.

11. What should one do during an asthmatic attack ?

It is important to stay calm during asthmatic attacks. If there is a recognizable trigger factor causing the attack, the sufferer should remove this if possible or move away from the environment that triggers.

Your doctor might have given a emergency treatment plan. This should be adhered to.

Generally, the immediate thing to do is to relieve the attacks with prescribed relievers. If the condition is not improved in 10 minutes, seek emergency medical help.

[Article Ref: Singapore Respiratory Specialists (SRS)]