Asthma does not have one single cause, but many factors may affect whether an individual is more likely to get this condition or not. Evidence suggests that you are more likely to have asthma if someone in your immediate family also has it, as there is a genetic component involved in this particular condition.
Allergies can also result in asthma, as can premature birth, bronchiolitis, or croup in babies. Smoking, workplace exposure and pollution can worsen your asthma. Obesity also is associated with asthma.
The cause of specific asthma attacks or issues is typically a trigger in or around the environment that a person is in. For example, individuals with allergies may have asthma triggered by pet dander, pollen, or dust. Exercise, infections, and cold air can all trigger asthma symptoms and potentially cause an asthma attack with prolonged exposure.