What is Asthma?

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Asthma is a chronic inflammation that affects the airways, which decreases the flow of air that enters and leaves the lungs. Symptoms appear differently in each patient and vary in frequency and severity. They consist of shortness of breath, chest oppression and cough, mainly during the night. Estimates show that there are more than 200 million people with asthma worldwide.

Asthma explained in first person

Professionals and patients explain how you live with the disease
The symptoms consist of shortness of breath, chest oppression and cough, mainly during the night.
It seems that people with asthma do not take their medication, which I can’t understand. If I don’t take my medication, I might not live, it’s as simple as that. So, prevention is taking your medication just like they tell you to, and when they tell you to.

Asthma is characterised by inflammation of the mucosa of the bronchi, which narrows them and makes the passage of air difficult. This is known as a bronchospasm.

How many people are affected?

Asthma is one of the most common chronic diseases at a world level. The World Health Organisation (WHO) estimates that there are 235 million people all over the world with asthma. Its prevalence is notably elevated in urbanised regions, associated with environmental changes and lifestyles. In Spain, it affects 5% of the adult population and up to 10% of the child population, taking into account that around 50% of the patients are still not diagnosed.

Types of Asthma

The respiratory inflammation can be classified depending on the triggering factors:

Patient with coughing due to allergic reaction to plants, pollen and animals

Allergic asthma. It occurs in association with the exposure to allergic substances that are in the environment (pneumo-allergens), such as pollen, dust mites, animal hairs, and fungi, among others. Depending on the type of allergen, the symptoms can appear in determined seasons of the year.

Patient with coughing in response to temperature changes and tobacco smoke

Non-allergic asthma. It is not related to allergies, and the symptoms can appear with sudden changes in temperature, as viral or bacterial respiratory infections, or exposure to irritant substances.

Man running; regular physical exercise

Asthma induced by exercise. The symptoms appear while performing physical exercise or just after finishing the activity.

Patient with occupational asthma cough

Occupational asthma. The symptoms appear due to the exposure of substances common to the work place (such as sawdust, flours, metals, plastic resins, among others.)

Depending on the frequency and severity of the symptoms, it can be classified into:

  • intermittent asthma and
  • persistent asthma. The latter may be mild, moderate, or severe.

Depending on the level of control of the symptoms under treatment, it can be classified as:

  • well-controlled asthma,
  • partially controlled asthma, or
  • uncontrolled asthma.

Substantiated information by:

Alejandra Lopez Giraldo
Antonio Valero Santiago
Irina Bobolea
Rosa Cortés Aguilar

Published: 20 February 2018
Updated: 20 February 2018

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