A risk factor is something that increases your likelihood of getting a disease or condition.

It is possible to develop asthma with or without the risk factors listed below. However, the more risk factors you have, the greater your likelihood of developing asthma. If you have a number of risk factors, ask your doctor what you can do to reduce your risk.

Risk factors for asthma include:

Genetics

It has been noted that asthma tends to run in families. People whose immediate blood relatives have asthma are more likely to develop the disease.

Genes and your environment play a role in the development of asthma. When asthma runs in families, genetic factors play a relatively large role. When asthma does not run in families, the genetic influence is not as significant as the environmental exposures.

Allergies

People who have allergies (especially allergic rhinitis and severe food allergies) have a greater chance of developing asthma. Allergens that may be associated with asthma include:

• Pollen
• Animal dander
• Mites
• Molds
• Dust and dust mites
• Certain foods

Medical Conditions

The following medical conditions increase your risk of developing asthma:

• Wheezing episodes before age 3 years old
• Respiratory infections in childhood
• Low birth weight
• Gastroesophageal reflux disease (GERD)
• Obesity

Age

Although asthma can develop at any age, the majority of cases are found in children between the ages of 2-17.

Exposure to Toxins

Frequent exposure to the following potential toxins increases your risk of developing asthma:

• Second-hand tobacco smoke
• Damp house and mold exposure
• Cockroach and dust-mite allergens
• Gas cooking
• Occupational irritants, such as chemicals used in:
  • Farming
  • Cleaning
  • Beauty salons
  • Painting
  • Manufacturing work
  • Wood work
• High levels of air pollution, particularly in an urban environment
• Chlorinated pool environment

Ethnic Background

Asthma affects people of all ethnic backgrounds. However, it is slightly more common in blacks and Hispanics than in whites.