What Is Asthma?
Asthma is a chronic inflammatory disease of the airways characterized by excessive sensitivity of the lungs, or increased reaction of the airways, to various environmental stimuli or triggers. The inflammation results in narrowed, swollen airways, increased mucus, and frequently is accompanied by tightening of the muscles in the airways, or bronchoconstriction, causing difficulty breathing and the familiar wheeze often associated with the disease. Despite the availability of many treatments for adults with asthma and guidelines on how to use them, the disease is still poorly controlled.
According to data from 2000, the annual direct healthcare cost of the disease in the U.S. is approximately $10 billion. Indirect costs (e.g., lost productivity due to missed days at school or work) add another $8 billion, for a total cost of $18 billion.