All about asthma

Asthma is a long-term respiratory condition that causes breathing difficulties, such as wheezing and breathlessness, which can range from mild to very severe. In the UK alone, more than 5 million people live with asthma.

Here to provide a comprehensive insight into asthma, including symptoms, diagnosis and treatment, is Dr Deepak Rao, renowned consultant respiratory physician based in London.

What is asthma, and what causes it?

The lungs are made up of very intricate breathing tubes that feed air from the outside to the inside of the lungs. Asthma is medically defined as an irreversible airway inflammation that impacts the larger parts of these breathing tubes, in which a trigger or event (such as an infection or allergen) causes inflammation in the linings of the tubes. This inflammation narrows the tubes, hence producing symptoms like wheezing.

What are the common symptoms of asthma?

Asthma produces a variety of symptoms.

It typically causes:

• a cough, which is mostly dry
• breathlessness
• wheezing (musical notes in your breath)

In addition, asthma can produce:

• tightness in your chest
• large amounts of very thick phlegm that are difficult to cough up
• non-specific symptoms, such as feeling tired, being unable to concentrate, and feeling quite lethargic

How is asthma diagnosed by healthcare professionals?

Asthma is generally divided into two broad categories:

• extrinsic asthma
• intrinsic asthma

Extrinsic asthma is asthma that is generally caused by external environmental triggers, such as pollen. The allergy markers in this type of asthma are quite elevated, both in the blood test and in the skin test, and it usually responds well to conventional treatment.

Intrinsic asthma, on the other hand, is asthma that isn’t related to any allergies or triggers. This type of asthma presents in the later part of life, around the third and fourth decade of life, and it is a little bit more difficult to manage.

In addition to these groups, asthma can be classified into smaller categories depending on the specific causes and triggers.

These categories include:

• exercise-induced asthma
• cough variant asthma
• pollution-induced asthma
• occupational asthma

The diagnosis of asthma, specifically, is based on a combination of clinical history and diagnostic testing.

We start by meticulously going through the chronology of the patient’s symptoms to identify what the precipitants or triggers were. This process also explores any family history of asthma and any potential triggers, such as allergies or skin rashes.

After a clinical history, the next step involves ordering several diagnostic tests.

Normally, these include routine blood tests, where we look for inflammatory markers to make sure there is no other cause for the inflammation in the breathing tubes. With these tests, we also look for a specific subset of inflammatory cells called cytokines.

Additionally, we order allergy tests of various allergens, such as pollen, dust mites and aspergillus, to help point towards a specific allergy. Included in these tests are also allergy blood tests to measure levels of total IgE, which can indicate an allergy.

Subsequently to these tests, we perform several lung function tests. These involve a spirometry test to measure the patient’s flow rates and lung volume, and a bronchodilator test to dilate the breathing tubes and then measure to see if there is a significant improvement.

Furthermore, we also measure fractional exhaled nitric oxide levels of phenol. This is a very specific marker that suggests an acute inflammation, and thus an acute asthma.

The other diagnostic test we perform is a peak flow test, which can be done at home. This test allows for a deeper understanding of the patient’s lung function over a period of two to four weeks.

We routinely don’t order chest x-rays, unless we want to rule out an infection as a cause.

What are the different types of asthma medications and their side effects?

Asthma medications can be broadly classified into:

• relievers, which immediately alleviate symptoms
• preventers, which prevent an asthma attack

In terms of relievers, the commonest are called short acting bronchodilators. Examples include ipratropium bromide and salbutamol, which is available as an inhaler. Short acting bronchodilators work immediately and last for about four to six hours. However, they don’t prevent the underlying pathology of asthma, which is the inflammation in the breathing tubes.

In terms of preventers, the commonest are a type of anti-inflammatory medications called corticosteroids. These are given in an inhaled form, which means that the dose consumed is very small and it is directed straight to the breathing tubes. As a result, less amounts of corticosteroids are typically needed, which helps reduce potential side effects.

Most often, we use combination inhalers, which are longer-lasting (for about 12 hours) short acting bronchodilators like salbutamol that are used in combination with corticosteroids. Combination inhalers have transformed the way we treat asthma and they have also significantly reduced the dependence on nebulisers, which are devices that deliver asthma medication in a very vaporised form.

Are there any natural remedies or lifestyle changes to manage asthma?

It is fundamental to know that conditions like obesity contribute quite significantly to either precipitating asthma or making asthma worse. For this reason, lifestyle changes play a significant role in managing asthma and keeping the respiratory muscles strong and toned.

These lifestyle changes include:

• eating a healthy diet
• practising regular exercise
• avoiding fizzy drinks
• managing your weight
• keeping yourself hydrated

On another note, relaxation techniques and biofeedback management are essential to manage asthma symptoms that are triggered by things like anxiety. Avoiding allergens, such as heavily scented perfumes, and keeping the home environment clean and stress-free is also important.

Smoking cessation and identifying the triggers of asthma are absolutely crucial.

How can asthma be prevented and controlled, especially in children?

Everything I mentioned beforehand is crucial.

In terms of incorporating a good lifestyle in children, parents can help by:

• encouraging their children to be fit and active
• keeping their children’s environment clean
• avoiding exposure to passive smoking

If children have an allergic tendency, it’s important to identify these allergies early on and incorporate measures to treat them effectively. If children are self-sustainable, encouraging them to use masks when they go out during the high-peak allergy season is quite important.

If you or your child are living with asthma, don’t hesitate to book an appointment with Dr Deepak Rao via his Top Doctors profile today to receive expert diagnosis, treatment and advice.