Press Room
Asthma Fact Sheet
What is asthma?
Asthma is a chronic inflammatory disease of the airways characterized by excessive sensitivity of the lungs, or increased reactivity of the airways, to various environmental stimuli or triggers.
The inflammation results in narrowed, swollen airways, and increased mucus production. Exposure to a trigger causes tightening of muscles in the airways, or bronchoconstriction, resulting in difficulty breathing and the familiar wheeze often associated with the disease. If not properly managed, asthma can be life-threatening.
What causes asthma?
Triggers range from respiratory infections to allergic reactions to airborne irritants. Other triggers may include certain foods, exposure to cold air or a sudden change in temperature, exercise, many household and industrial products, scents, or excitement or stress. Each person reacts differently to these factors.
Examples of triggers include:
- Pollen
- Molds
- Animal dander
- Feathers
- Dust
- Cigarette smoke
- Air pollutants
Is asthma a serious problem?
Asthma is one of the most serious chronic medical conditions in the United States. It is estimated that 20 million Americans live with the disease. 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. In 2004, an estimated 14.5 million lost work days in adults were attributed to asthma.
U.S. mortality figures
- More than 4,000 Americans died from asthma in 2003
- Non-Hispanic blacks are the most likely group to die from asthma; their death rate is more than double the rate of the white population and 54 percent higher than Hispanics
- Women have an 80 percent higher death rate from asthma than men
What happens during an asthma attack?
During an attack, or episode, the lining of the airways become inflamed and swollen. There also may be an increase in mucus production as well as tightening of the muscles around the airways. As a result, the air passages in the lungs become narrower and breathing becomes more difficult.
What are the symptoms of asthma?
During an asthma attack, a person may have difficulty breathing and may begin to breathe very fast. This may or may not be associated with exercise. In addition, a person may feel short of breath, even at rest. Although a person may be symptom-free for long periods of time, he or she can experience acute (sudden onset) or intermittent attacks. Other symptoms of asthma may include the following:
- Coughing
- Wheezing or whistling
- Chest tightness
How is asthma treated?
Most people with asthma take two kinds of medicines, a controller (maintenance) and a quick-relief (rescue). A controller, or maintenance, medicine helps control inflammation and prevents the airways from reacting to asthma triggers, so a person can breathe easier. Controller/maintenance medicines work best if taken every day, as prescribed by a physician.
The goal of maintenance therapy is to maintain lung function and health, and reduce the risk of recurrent asthma attacks.
Examples of controller/maintenance medicines include:
- Oral corticosteroids — help to decrease inflammation in the lungs in multiple ways
- Inhaled corticosteroids — help to decrease inflammation in the lungs
- Long-acting beta2-agonists (LABA) — relax the muscles around the airways in the lung
- Combination therapies — combine the benefits of a corticosteroid and LABA in one inhaler
- Leukotriene modifying agents — decreases inflammation from one specific set of inflammatory pathways
- Cromolyn and Nedocromil Sodium — prevent airways from swelling
- Anti-IgE therapy (injected) — attempts to stop allergic asthma at its root cause
The other kind of asthma medicine is a quick-relief/rescue, medicine (also known as a bronchodilator). These drugs are inhaled and work by dilating, or expanding, the airways to make it easier to breathe. They should only be used for quick relief of coughing and wheezing, or to relieve chest tightness.