Causes of Asthma

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Sun, wind, rain and waves as environmental factors

Environmental stimulants. In asthma, the mucosa of the bronchi is inflamed and narrowed, restricting the passage of air, which is known as bronchial hyper-reactivity. It can be produced by environmental stimulants, such as: cold air, exercise, allergens, respiratory infections, emotional stress, tobacco smoke, environmental contamination, irritant chemical products, among others.

DNA molecule or helix

Genetic factors. Along with the environmental factors, they induce and predispose to the appearance of the disease.

The mechanisms that cause the bronchial inflammation are very complex, since different cells and inflammatory mediators are involved, and are the subject of continuous scientific research.

Risk factors of Asthma

The risk of suffering asthma is determined by the interaction between genetic predisposition, the factors that modify the development of the individual, before birth or during infancy, and the environmental exposure to inhaled particles.

Some known risk factors are:

Family tree

To have a history of asthma in a close relative, such as father, mother or brothers and sisters.

Pregnant woman smoking

Smoking by the mother during pregnancy.

Position of the premature baby

Born prematurely or low weight.

Girl with a lung infection

To have certain respiratory viral infections during the first months or years of life.

Respiratory sounds or lung whistles

To have “whistles” or wheezing in the first years of life.

Face with dry skin

To have a predisposition to present with allergies, which is called “atopy”; such as rhinitis, dermatitis, and allergic conjunctivitis.

Scale with an arrow pointing upwards indicating a weight increase




Second-hand smoker receiving smoke from a smoker

To be a passive smoker.

Factory with a smoky, polluting chimney

To live in urban and industrialised areas, especially in places that have a high level of environmental contamination.

Erlemeyer flask and measuring cylinder

Exposure to chemical products (including, agricultural, hairdressing, or construction) in the work environment.

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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