Asthma is a condition that causes episodic breathing difficulties. These episodes are caused by narrowed and inflamed airways of the lungs. Asthma flare-ups or attacks can be triggered by dust, pollutants, smoke, allergies, cold air, or infections.

Winning Ways

Jackie Joyner-Kersee (b. 1962) has often been called the world's greatest female athlete. What many fans never suspected is that she is also an asthmatic. Joyner-Kersee became active in sports at the age of 9. As a teenager, she was an all-state player in basketball and a Junior Olympics champion in the pentathlon, an athletic contest in which each person takes part in five different events. While still in high school, Joyner-Kersee began having trouble breathing. When she first found out that she had asthma, she did not take it seriously. She often skipped her medicine. After a serious asthma attack, she realized that she had to work to control the condition just as she worked to win at sports. After college, Joyner-Kersee went on to win six Olympic medals as well as to break the world and Olympic records in the heptathlon, an athletic contest with seven different events: 100-meter hurdles, high jump, shot put, 200-meter dash, long jump, javelin, and 800-meter race. In the early 2000s, she served as a spokesperson for groups that educate the public about asthma.

A Breathless Story

When Stacy was young, her parents noticed that she seemed to get tired more quickly than her friends while playing. She also had repeated coughing spells, and her breathing was sometimes noisy. After examining Stacy, asking lots of questions, and having her use a little machine to measure her breathing, the doctor diagnosed her problem as asthma. As part of the way Stacy took care of herself, she sometimes had to take asthma medicine at school. This medication made her teachers and friends interested in learning more about asthma. When Stacy was 12, she began a school-wide project with the help of her teacher and the school nurse. The goal was to make her school more comfortable for those who have asthma. No smoking was allowed, even during after-school events. Extra measures were taken to keep the school as free as possible of substances that could trigger asthma flare-ups, such as dust; mold; cockroach saliva, feces, or shedding body parts; and strong fumes from paint and chemicals. A plan was set up that allowed students with asthma to take their own medicines at school. Special lessons were offered to all students and teachers about what asthma is and how to help a classmate who has it. The result was a school that was a healthier place not just for Stacy but for everyone.

What Is Asthma?

Several changes happen inside the airways in the lungs of people who have asthma. First, there is inflammation, or swelling, of the lining of the airways. Second, the swollen tissues make a thick, slippery substance called mucus * . Third, the muscles around the airways may squeeze tight, causing the airways to narrow. These three processes—inflammation, mucus production, and muscle constriction—combine to reduce the size (the diameter) of the airways. That makes it harder to breathe, like trying to blow air through a narrow straw.

During an asthma attack, these changes get worse. The airways swell on the inside while they are being squeezed on the outside. At the same time, thick mucus plugs the smaller airways. The person may start to make whistling or hissing sounds with each breath. The person's chest may also feel tight. In addition, the person may cough to try to clear the lungs.

What Are the Severities of Asthma?

Cases of asthma vary in severity. Some people may have only mild symptoms a few times per month, whereas others may have severe symptoms every day. Asthma has four levels, depending on how severe each case is.

The stages of an asthma attack.

The stages of an asthma attack.
Illustration by Frank Forney. © 2016 Cengage Learning®.

A person with this type of asthma has daytime symptoms less than twice per week and nighttime symptoms less than twice per month. Attacks are brief and usually do not affect activities. Intermittent means that the symptoms come and go.

Mild persistent

A person with this type of asthma has mild symptoms more than twice per week, never more than once per day. Nighttime symptoms occur more than two times a month.

Moderate persistent

A person with this type of asthma has symptoms every day and flare-ups more than twice per week. Nighttime symptoms occur more than once per week. When symptoms do occur, they can last for days and can make it hard for the sufferer to participate in certain activities.

Severe persistent

A person with this type of severe asthma has symptoms throughout the day and night. The asthma makes it hard or impossible for a person to participate in many physical activities.

What Triggers Asthma?

People with asthma have what are sometimes called “sensitized” airways. Everyday factors that cause little or no trouble for most people can sometimes cause people with asthma to have a flare-up or attack. These factors are known as asthma triggers. There are two main kinds of triggers: allergic and nonallergic. An allergic trigger results from substances called allergens * , which trigger an allergy. Examples of allergens that may trigger asthma are pollens, molds, animal dander (small scales from fur or feathers), dust mites * , cockroach saliva, feces, or shedding body parts, and certain foods and medicines. Most of these allergy-causing substances enter the body through the air that people breathe, but some are swallowed.

Breathtaking Facts: Asthma in the United States

Who Gets Asthma?

Asthma is one of the most common health problems in the United States. It can affect both children and adults, and is the most common chronic * health problem seen among children and teenagers. Childhood asthma is slightly more common in boys than girls. The condition is also more common among African American children than Caucasian children, although the reason for this difference is not clear. It may have to do with environmental conditions.

What Are the Symptoms?

The following are the most common symptoms of asthma. A person may have all, some, or just one of these symptoms:

The degree to which asthma interferes with a person's daily life varies significantly. Some people have ongoing problems. The frequency of their attacks may range from several times per week to almost constantly. Their ability to take part in physical activities may be limited until they are able to get their asthma under control with treatment. Those with milder problems are usually able to do whatever they want to do, so long as they reduce their environmental triggers, take their medicine as directed, and follow any other advice from their doctors.

Childhood asthma

The word asthma comes from the Greek word for “panting,” which is a symptom that occurs in several different pulmonary (lung) disorders.

Asthma was first described as a disease rather than a symptom by the English chemist Thomas Willis (1621–1675).

In 1698, Sir John Floyer (1649–1734) gave the first formal account of an asthma attack or “fit.” An accurate diagnosis of asthma was not possible until the early 19th century, when the celebrated French physician René Laënnec (1781–1826) invented the stethoscope * .

During the early 19th century, asthma was treated in a variety of ways, including by taking whiffs of chloroform and even by smoking ordinary tobacco.

Nighttime asthma

Asthma tends to get worse at night. Nocturnal (or nighttime) asthma occurs while a person is sleeping. For some people, nocturnal asthma is one of many symptoms; other people seem to have coughing or wheezing only at night. The greatest amount of constriction of the airways experienced by people with nighttime asthma occurs between the hours of 4:00 λ.μ. and 6:00 λ.μ. This is also the time frame during which most symptoms are experienced and deaths from asthma are more likely to occur.

Exercise-related asthma

Many people with asthma have trouble with noisy breathing during or after exercise, a condition known as exercise-induced asthma. Other symptoms include coughing, a rapid heartbeat, and a feeling of tightness in the chest 5 to 10 minutes after exercise. For some people, exercise is the only asthma trigger. That means they have asthma symptoms only after exercise-like activities and do not have symptoms at any other time. Cold or dry air, high pollen counts, air pollution, a stuffed-up nose, and an infection of the airways are all factors that tend to make the problem worse. Types of exercise that may lead to wheezing include swimming, running, using a treadmill, and playing basketball—exercises that are aerobic (designed to increase oxygen consumption).

Job-related asthma

Occupational asthma is caused by breathing fumes, gases, or dust while on the job. Asthma can start for the first time in a worker who was previously healthy, or it can get worse in a worker who already had the condition. Symptoms include wheezing, chest tightness, and coughing. Other symptoms that may go along with the asthma include a runny or stuffed-up nose and red, sore, itchy eyes. The asthma may last for a long time, even after the worker is no longer around the substance that caused it.

Other factors linked to the development of asthma include obesity, family history of asthma, sensitivity to aspirin especially in adults with nasal polyps * , and gastroesophageal reflux disease (GERD). *

Severe attacks

Status asthmaticus (STA-tus az-MAT-i-kus) is a severe asthma attack that does not get better when individuals take their medicine as usual. This kind of attack is an emergency that must be treated right away in a hospital, where other medicines may be used.

How Is Asthma Diagnosed?

The doctor performs a physical checkup and asks questions about symptoms and when they occur. In addition, the doctor may do various tests to help identify asthma and its causes.

Allergy tests

Allergy tests help identify those substances to which a person is allergic. Skin tests are most common. Tiny amounts of possible allergens are put on the skin, and the skin is checked to see which substances, if any, cause a reaction. In another type of allergy test, a blood sample is checked for certain antibodies, which are substances made in the blood that fight foreign or harmful substances. People with allergies may have high levels of immunoglobulin E (IgE) antibodies. The blood test is generally not considered as precise as the skin test, and it cannot check for as many allergens.

Chest x-ray

An x-ray is an invisible wave that goes through most solid matter depending on its density and produces an image on film. After the film is developed, a special picture can be viewed that shows how the lungs and other structures look. An x-ray can help rule out other causes of wheezing.

Lung function tests

These tests show how well the lungs are working. In one test, the person blows into a device called a spirometer (spi-ROM-i-ter), which measures the amount of air going in and out of the lungs. Another test uses a peak flow meter to measure how fast the person can breathe air out of the lungs. A peak flow meter is a simple handheld device that can be used at home. Many people with asthma use peak flow meters regularly to check for early warning signs of an upcoming asthma attack. Doing so gives them time to take certain medicines that can often stop the attack.

Why Is Treatment Needed?

Asthma that is not under control can cause many problems. People miss school or work, must go to the hospital, and can even die (rarely) because of asthma. With treatment, most people can control their asthma. People with well-controlled asthma have few if any symptoms during the day and can sleep well at night. They can also take part in their usual activities, including sports and exercise. Asthma does not go away just because its symptoms do. Individuals need to continue taking care of their condition: avoiding triggers, not smoking, and living in a healthful, clean environment. Ongoing attention is required even in mild asthma cases.

How Is Asthma Treated?

Besides avoiding exposure to asthma triggers, asthma is mostly treated with medicines. There are two characteristics of asthma: inflammation and spasms (or constriction) of the muscles in the airways. Asthma treatment focuses on both. Asthma medicines fall into two groups: those used to prevent symptoms and control the disease for a long time, and those that give short-term relief during an asthma attack. Taking the right medicine at the right time is important.

Long-term control medicines

Long-term control medicines are taken every day to help prevent symptoms from starting. It may take several weeks for these medicines to produce their best results. The most effective ones work by reducing swelling in the airways. Many are inhaled (breathed into the lungs). Not everyone needs such medicines. They may be very helpful for people who have daytime asthma symptoms three or more times per week, or nighttime symptoms three or more times per month. Medicines for long-term control of asthma include the following: