Asthma is a disease of the lungs in which the airways are inflamed. Exposure to allergens and irritants cause asthma flare-ups. Several things happen to the airways when a person is exposed to allergen or irritant triggers:
The lining of the airways becomes swollen and inflamed.
The muscles that surround the airways tighten.
More mucus is produces leading to mucus plugs in the airways
The airways then narrow, making it difficult for air to go in and out of your lungs.
Asthma may resemble other respiratory problems, such as emphysema, bronchitis, and lower respiratory infections. Many people with the disease do not know they have it. Sometimes, the only symptom is a chronic cough, especially at night, or coughing or wheezing that occurs only with exercise. The most common symptoms are:
Wheezing, or whistling sound when breathing
Shortness of breath
The exact cause of asthma is not completely known. It is believed to be partially inherited, but it also involves many other factors. After a person is exposed to a certain trigger, the body releases substances that can cause inflammation in the airways. The body also releases substances that can cause the muscles of the airways to tighten or become smaller. There is also an increase in mucus production that may clog the airways.
Some people have exercise-induced bronchoconstriction (a narrowing of airways that occurs with exercise). Symptoms occur during, or shortly after, exercise. In some people, stress or strong emotions can trigger an asthma attack. Each person has different triggers that cause symptoms. Discuss your triggers with your health care provider.
The changes that occur in asthma are believed to happen in two phases, one that happens right away and a second response 4 to 8 hours later. They both cause swelling and narrowing of the airways.
Although anyone can develop asthma , it most commonly occurs in the following people:
Children and adolescents ages 5 to 17
People living in cities
Other factors include the following:
Family history of asthma
Personal history of allergies
Exposure to secondhand tobacco smoke
People with asthma have acute episodes when the air passages in their lungs become narrower, and breathing becomes more difficult.
Breathing becomes harder and may become painful.
Talking and sleeping may be difficult.
Coughing and mucus production may increase.
Wheezing may occur.
Medical history and physical exam bare used to diagnosed asthma. The following test may also be done:
Spirometry. A spirometer is a device that assesses lung function. The test is done by blowing as hard as possible into a tube connected to a spirometer. It measures the amount and speed of air breathed out. Spirometry is done to:
Monitor a lung disease
Monitor the effectiveness of treatment
Determine the severity of a lung disease
Peak flow monitoring (PFM). This measures the fastest speed in which a person can blow air out of the lungs. A person takes a deep breath in and then blows as hard and fast as possible into a mouthpiece. The changes that occur with asthma slow the speed of air leaving the lungs and can be measured by a PFM. This measurement is very important in evaluating how well asthma is being controlled.
Blood tests. Tests to measure the amount of carbon dioxide and oxygen in the blood.
According to the CDC, the American Academy of Allergy, Asthma, and Immunology, and other organizations, triggers for asthma include the following:
Animal protein (dander, urine, oil from skin)
House dust or dust mites
Infections can cause irritation of the:
Strong odors and sprays, such as perfumes, household cleaners, cooking fumes, paints, and varnishes
Chemicals, such as coal, chalk dust, or talcum powder
Air pollutants, such as chemicals in the air and ozone
Changing weather conditions, including temperature, barometric pressure, humidity, and strong winds
Chemical exposure on the job, such as dust, gases, or fumes.
Other nonsteroidal anti-inflammatory medications (NSAIDs), such as ibuprofen, indomethacin, naproxen
Sulfites used as preservatives in food and beverage
Gastroesophageal reflux (GERD)
Strenuous physical exercise such as long-distance running.
Common in people with asthma. Symptoms may include heartburn, belching, or spitting up in infants.
Anxiety and stress
Tobacco smoke from inhaling or from secondhand smoke.
Wood smoke from wood-burning heating stoves and fireplaces
Can cause fatigue, which may affect the immune system and increase asthma symptoms or cause an attack.