Multiple: Asthma

Definition
Description
Demographics
Causes and Symptoms
Diagnosis
Treatment
Prognosis
Prevention
The Future
For more information

Definition

Asthma is an inflammatory disorder of the airways leading to the lungs. The disease causes the airways to constrict and produce mucus that makes breathing difficult. Asthma is considered an atopic disease along with eczema and hay fever.

Description

The symptoms of asthma vary from person to person. Some people diagnosed with asthma have occasional episodes of mild wheezing or coughing but are able to breathe normally in between such episodes. Others may have life-threatening attacks in which they turn blue for lack of oxygen, experience severe chest pain, and may even lose consciousness.

Doctors classify asthma into four categories of severity:

• Intermittent: The patient has asthma episodes less than once a week; can breathe normally between episodes; and does not need daily medication.
• Mild persistent: The patient has episodes more often than once a week but less than once a day; the episodes sometimes affect sleep and activity levels; and the patient can control symptoms by using an inhaler.
• Moderate persistent: The patient has episodes every day; the symptoms affect sleep and activity levels; and the patient needs long-acting oral medications as well as an inhaler.
• Severe persistent: The patient has continuous symptoms; is frequently disturbed at night and must limit daytime activity; needs steroid medications as well as oral drugs and long-acting inhalers.

Demographics

Asthma is one of the most common chronic (long-term) diseases around the world and is the single most common cause of hospitalization for children in the United States. According to American Academy of Allergy, Asthma and Immunology (AAAAI), 20 million people in the United States

have asthma, with 9 million children under the age of eighteen diagnosed with the disease. Two-thirds of all cases of asthma in North America are diagnosed in children before age eighteen.

Asthma is responsible for about 500,000 hospitalizations each year in the United States and 5,000 deaths. There are about 13 million physician office visits and 1.2 million outpatient department visits due to asthma. Children with asthma miss about 13 million days of school each year and adults with asthma miss 25 million work days. The annual costs to the American economy for asthma are $11.5 billion for direct health care and $5 billion for lost productivity.

Risk factors for asthma include:

• A family history of asthma.
• Living in a large city.
• Exposure to secondhand smoke in the home.
• Exposure to chemicals used in farming, manufacturing, dry cleaning, hairdressing, and other occupations.
• Race. African Americans and Puerto Ricans in the United States have higher levels of asthma than members of other races, including Native Americans and Pacific Islanders.

• Gender. Boys are twice as likely as girls to develop asthma in childhood, but by adolescence the numbers are equal. Women are more likely than men to be diagnosed with asthma as adults.
• Obesity.
• Low birth weight.

Jackie Joyner-Kersee

Jackie Joyner-Kersee (1962–) is a retired Olympic champion who was voted the greatest woman athlete of all time by Sports Illustrated for Women. Named after former First Lady Jackie Kennedy, Joyner-Kersee began her career in sports at the University of California at Los Angeles in 1980. She participated in basketball and track and field events. Between 1984 and 1996, Joyner-Kersee won three gold, one silver, and two bronze medals in four different Olympic Games.

Joyner-Kersee was diagnosed with asthma during her freshman year of college but did not take her diagnosis seriously. Like many people treated for asthma, she felt good enough from time to time to stop taking her long-term medications on a regular basis. She had several close calls that sent her to the emergency room, then she experienced a nearly fatal asthma attack in 1993. She resolved not only to take her own health more seriously but also to travel across the United States educating children diagnosed with asthma about the importance of getting treatment. In 2007 Joyner-Kersee joined sports stars Lance Armstrong, Cal Ripken Jr., Muhammad Ali, and Andre Agassi to form a charitable organization called Athletes for Hope. Joyner-Kersee herself hosted the 2008 Winning for

Life track and field event, which draws more than 1,000 female student athletes from four Midwestern states.

Causes and Symptoms

The basic cause of asthma is the hypersensitivity of the person's airway to some trigger in the environment. When the tissues in the airway react to the trigger, they constrict (become narrower), which reduces the amount

of air that can flow into, and especially out of, the lungs. The inflamed tissues also secrete mucus, which further limits the airflow in the bronchi and adds to the wheezing, coughing, and feeling of tightness in the chest that are part of an asthma attack.

Most doctors think that genetic factors are partly responsible for the sensitivity of the lung tissues in asthma patients. It is known that the disorder runs in families. At least twenty-five different genes have been associated with an increased risk of asthma in six or more separate groups of people. Researchers still do not understand, however, exactly how these genes (or others that may be discovered in the future) interact with triggers in the environment to produce the symptoms of asthma.

Specific triggers that can produce asthma attacks in patients include:

• Allergens carried in the air. These include pollen, dust, mold, pet dander, and cockroach droppings.
• Getting a cold or other upper respiratory infection.
• Physical exercise. This is called exercise-induced asthma or EIA.
• Cold dry air.
• Tobacco smoke and other air pollutants.
• Medications, particularly aspirin, other nonsteroidal anti-inflammatory drugs (NSAIDs), and beta blockers (heart drugs).
• Foods that cause allergic reactions. Common offenders are peanuts, shellfish, and eggs.
• Gastroesophageal reflux disease (GERD).
• The menstrual cycle in some women.
• Emotional stress or tension.
• Shampoo, hair gel, fabric softener, deodorant, cologne, air freshener, shaving lotion, scented tissues, and similar personal and household products.
• Chlorinated swimming pool water.

Diagnosis

Asthma can be difficult to diagnose, particularly in children younger than five years, because the symptoms can vary considerably in frequency and severity. In some cases, the person's symptoms may be misdiagnosed as a bad cold, pneumonia, or emphysema. To narrow the diagnostic possibilities, the doctor will take a family history as well as the patient's medical history and give the patient a complete physical examination.

The next step in diagnosis is to test the patient's lung function. There are several tests that can be done:

• Spirometry. A spirometer is a machine that measures the largest amount of air that a person can breathe out after taking a very deep breath.
• Peak airflow meter. This is a device that can be used at home as part of an asthma action plan to detect minor changes in lung capacity before the symptoms of an asthma attack appear. The meter can be used in the doctor's office to measure lung function. The patient may be asked to use the meter before and after taking a dose of a bronchodilator, which is a type of drug that opens up the airway. If the patient's reading on the peak airflow meter improves after taking the bronchodilator, he or she is likely to have asthma.
• Bronchial challenge test. In this type of test, a small amount of a drug that is known to trigger asthma is given to the patient. If the patient's airway narrows after taking the drug, he or she is diagnosed with asthma. The bronchial challenge test is particularly useful in identifying patients with intermittent asthma.

Treatment

Treatment for asthma is based on the severity and frequency of the patient's symptoms and is aimed at controlling symptoms or preventingepisodesofasthma. Thereisnocurefor thediseasecurrently. Most asthma patients need a combination of long-term control medications and quick-relief or rescue medications. The long-term drugs are taken every day over long periods of time to prevent asthma attacks. They may take several weeks to become fully effective. The long-term medications given to control asthma include inhaled corticosteroids, long-acting inhaled bronchodilators, or oral medications like theophylline.

Quick-relief or rescue medications include oral corticosteroids and short-term bronchodilators like Atrovent or albuterol. The effects of rescue medications last between four and six hours. A patient who needs these drugs very often probably needs to have his or her long-term medications adjusted.

Asthma patients who are allergic to specific foods or airborne allergens may need treatment for their allergies as well as their asthma.

Prognosis

About half of all children diagnosed with asthma outgrow their disease by their late teens or early twenties and do not need further treatment. Patients who develop asthma as adults are more likely to have chronic health problems related to the disease.

Prevention

People cannot prevent getting asthma, but they can reduce the frequency and severity of asthma attacks by following the recommendations of the Centers for Disease Control and Prevention (CDC):

• Draw up an asthma action plan with the family doctor. The CDC recommends the sample plan found at http://familydoctor.org/online/famdocen/home/common/asthma/basics/696.html
• Identify and avoid personal asthma triggers.
• Learn to identify the warning signs of an asthma attack.
• Monitor breathing periodically by taking measurements at home with a peak air flow meter.
• Treat attacks early. Quick action reduces the likelihood of a severe attack.
• Take asthma medications as directed. Do not stop taking them without consulting the doctor even though the asthma seems to be getting better.

The Future

Asthma is a concern to public health doctors because its rates have risen rapidly in the United States since the 1960s. The number of children under the age of five diagnosed with asthma rose 160 percent from 1980 to 2006. Similar increases have been reported in other developed countries, including Canada, Australia, New Zealand, Germany, and the United Kingdom. Some of the explanations that have been offered for the increase include people moving from rural areas into cities; air pollution; increased exposure to chemicals in the environment; and increased exposure to tobacco smoke in the household. It is expected that asthma rates will continue to rise in developed countries over the next several decades.

SEE ALSO Eczema; Gastroesophageal reflux disease; Hay fever; Sleep apnea; Smoking

WORDS TO KNOW

Allergen: A substance that causes an allergic reaction in individuals who are sensitive to it.

Atopic disease: Any allergic disease that affects parts of the body that are not in direct contact with the allergen. Asthma, eczema, and hay fever are all atopic diseases.

Bronchodilator: A type of drug that opens up the bronchi, increasing airflow and relieving wheezing and other asthma symptoms.

Bronchus (plural, bronchi): One of the two major divisions of the airway that lead into the right and left lungs.

Chronic: Long-term.

Peak airflow meter: A handheld device that asthma patients can use at home to monitor their lung capacity in order to treat the warning signs of an asthma attack as soon as possible.

Spirometer: A device that is used to test the air capacity of a person's lungs and the amount of air that enters and leaves the lungs during breathing.

Wheezing: A continuous harsh whistling sound produced by the airways of an asthma patient when the air passages are partly blocked.

For more information

BOOKS

Berger, William E. Living with Asthma. New York: Facts on File, 2008. Landau, Elaine. Asthma. New York: Marshall Cavendish Benchmark, 2009. Powell, Jillian. Asthma. North Mankato, MN: Cherrytree Books, 2007.

PERIODICALS

Moran, W. Reed. “Jackie Joyner-Kersee Races against Asthma.” USA Today, January 31, 2002. Available online at http://www.usatoday.com/news/health/spotlight/2002/01/31/spotlight-kersee.htm (accessed September 21, 2008).

WEB SITES

American Academy of Allergy, Asthma and Immunology (AAAAI). Adult Asthma. Available online at http://www.aaaai.org/patients/gallery/adultasthma.asp (accessed September 20, 2008).

American Academy of Allergy, Asthma and Immunology (AAAAI). Childhood Asthma. Available online at http://www.aaaai.org/patients/gallery/childhoodasthma.asp (accessed September 20, 2008).

American Academy of Family Physicians (AAFP). Sample Asthma Action Plan. Available online at http://familydoctor.org/online/famdocen/home/common/asthma/basics/696.html (updated May 2006; accessed September 20, 2008).

American Lung Association. What Is Asthma? Available online at http://www.lungusa.org/site/apps/nlnet/content3.aspx?c=dvLUK9O0E&b=4294229&ct=5314727 (accessed September 20, 2008).

Centers for Disease Control and Prevention (CDC). You Can Control Your Asthma. Available online at http://www.cdc.gov/asthma/faqs.htm (accessed September 20, 2008).

Mayo Clinic. Asthma. Available online at http://www.mayoclinic.com/health/asthma/DS00021 (updated May 31, 2008; accessed September 20, 2008).

National Heart, Lung, and Blood Institute (NHLBI). What Is Asthma? Available online at http://www.nhlbi.nih.gov/health/dci/Diseases/Asthma/Asthma_WhatIs.html (updated May 2008; accessed September 20, 2008).

TeensHealth. What's Asthma?. Available online at http://kidshealth.org/teen/asthma_basics/what/asthma.html (updated March 2007; accessed September 20, 2008). Page includes an animation of the way to use a peak flow meter.