Although asthma can develop without any risk factors, the number of risk factors you have increases your risk of developing the disease.
The following factors can increase the risk of asthma:
- family history;
- allergies (including allergy-related conditions such as eczema and allergic rhinitis);
- multiple respiratory infections in childhood;
- age – although asthma can occur at any age, it is more common in childhood;
- frequent exposure to possible allergens – including dust mites, second-hand smoke, pet dander, and workplace irritants or chemicals (eg, toluene);
- sex – during childhood, boys have asthma more frequently than girls; however, this trend reverses after puberty, with men and women having approximately equal rates of asthma in adulthood.