Asthma Basics

There are three major features of asthma:

1. Airway obstruction. During normal breathing, the bands of muscle that surround the airways are relaxed, and air moves freely. But in people with asthma, allergy-causing substances and environmental triggers make the bands of muscle surrounding the airways tighten, and air cannot move freely. Less air causes a person to feel short of breath, and the air moving through the tightened airways causes a whistling sound known as wheezing.

(Fortunately, this airway narrowing is reversible, a feature that distinguishes asthma from other lung diseases such as bronchitis or emphysema.)

2. Inflammation. People with asthma have red and swollen bronchial tubes. This inflammation is thought to contribute greatly to the long-term damage that asthma can cause to the lungs. And, therefore, treating this inflammation is key to managing asthma in the long run.

3. Airway irritability. The airways of people with asthma are extremely sensitive. The airways tend to overreact and narrow due to even the slightest triggers such as pollen, animal dander, dust or fumes.

Who Gets Asthma?

Asthma affects 12-15 million Americans, including approximately 10%-12% of children under age 18. Asthma may occur at any age, although it's more common in younger individuals (under age 40).

People who have a family history of asthma have an increased risk of developing the disease. Asthma is also more common in people who have allergies or who are exposed to tobacco smoke.

However, anyone can develop asthma at any time.

What Causes Asthma?

People with asthma have very sensitive airways that react to many different things in the environment called "triggers." Contact with these triggers cause asthma symptoms to start or worsen. The following are common triggers for asthma:

• Infections (colds, viruses, flu, sinus infection)
• Allergens such as pollens, mold spores, pet dander and dust mites
• Irritants such as strong odors from perfumes or cleaning solutions, air pollution,
• Tobacco smoke
• Exercise or exertion
• Weather -- changes in temperature and/or humidity, cold air
• Strong emotions such as anxiety, laughter or crying, stress

What Are the Symptoms of Asthma?

People with asthma experience symptoms when their airways tighten, swell up, or fill with mucus. Common symptoms include:

• Coughing, especially at night
• Wheezing (a high-pitched whistling sound when breathing out)
• Shortness of breath
• Chest tightness, pain, or pressure

Not every person with asthma has the same symptoms in the same way. You may not have all of these symptoms, or you may have different symptoms at different times. Your symptoms may also vary from one asthma attack to the next, being mild during one attack and severe during another.

An asthma attack is a sudden worsening of symptoms.

How Is Asthma Diagnosed and Treated?

If you suspect that you may have asthma, see your doctor. He or she can run tests to determine if you have it.

If a diagnosis is made, there are many treatments available to make you feel better and improve the underlying problems that caused the asthma.