Bronchial asthma, often referred to simply as asthma, is a chronic condition which causes inflammation of the bronchioles, or airways. This inflammation reduces airflow to the lungs, often causing wheezing, coughing, and shortness of breath. Bronchial asthma is an extremely common condition, affecting around 22 million people in the United States, and more than 300 million worldwide.
There are many common asthma triggers. These include animal hair and dander, dust, mold and pollen, food additives, chemicals, and tobacco smoke. Strong emotions, especially stress, may also trigger asthma attacks. An asthmatic person is also more likely to experience an attack when he or she has a respiratory infection. The extent and nature of triggers varies from person to person; however sensitivity to a particular trigger may tend to run in families, just as asthma itself does.
When a person with asthma comes into contact with a triggering substance, he or she is likely to experience an acute asthma attack. During such an attack, the immune system mounts an almost immediate reaction to the triggering substance. As a result of this immune reaction, airway muscles contract strongly, and the airway itself begins to swell. In addition, the cells of the airways may begin to produce large amounts of mucus. All of these reactions serve to narrow the airways, making breathing more difficult.
As a result of studies which examine the prevalence of asthma in sets of identical and non-identical twins, it is now known that bronchial asthma is partially genetically inherited. In addition, it seems that environmental factors also determine whether a given individual will develop asthma. Research suggests that if an individual possesses genes which increase susceptibility to asthma, those genes play the most important role in determining whether he or she will develop asthma. If the genes are not present, then environmental factors play a stronger role.
There are two main types of treatment for bronchial asthma: medications which are taken to reduce the frequency of asthma attacks, and medications which can be used during an attack to reduce its severity. Preventative medications include corticosteroids to reduce inflammation, and bronchodilators to help prevent airway muscles contracting. More powerful versions of these medications can be used during an attack to relieve acute symptoms of asthma.
Symptoms of bronchial asthma can be reduced in severity and frequency by avoiding known asthma triggers. The use of hypoallergenic bedding can help people who are triggered by dust, for example, and avoiding chemical fumes, animal hair and dander, and mold, can help prevent chronic symptoms and acute attacks of asthma. For children in particular, ensuring the home is free from cigarette smoke is one of the most effective ways of reducing asthma symptoms.