Understanding Asthma

by Health Canada

With the right information, treatment and support, most people with asthma can control their symptoms and lead active, healthy lives.

Asthma is a chronic lung disease that can be fatal. An estimated 2.7 million Canadian adults and children (ages 4 years and over) have asthma. Asthma is also an important factor in school absences and hospitalizations in children.

Although 287 Canadians died of asthma in 2003, mortality rates for asthma have fallen since 1990. This coincides with various national efforts to improve control of the disease.

Causes and Symptoms of Asthma

The exact cause of asthma is not known, but it appears to result from the complex interaction of a number of factors, including:

• predisposing factors, such as the tendency to have an allergic reaction to foreign substances
• causal factors, which may sensitize the airways (e.g. cat and other animal dander, dust mites, cockroaches or workplace contaminants), and
• contributing factors, which may include such things as exposure to tobacco smoke during pregnancy and childhood, frequent respiratory infections, and indoor and outdoor air quality

The symptoms of asthma include cough, shortness of breath, tightness in the chest, and wheezing. Asthma symptoms and attacks (i.e. episodes of more severe shortness of breath) usually occur after exposure to "triggers." Some of the common triggers are allergens, viral respiratory infections (e.g. a cold), exercise, or exposure to irritant fumes or gases.

When people with asthma are exposed to triggers, the airways in their lungs become inflamed and swollen. As a result, the airways start to narrow and it becomes more difficult to breathe. During some asthma episodes or attacks, the muscles around the airways can also tighten and the airways can produce mucus. These conditions make it even harder to breathe.

The presence of "asthma-like" symptoms does not always mean that someone has asthma. A diagnosis is usually confirmed by medical tests.

Managing Asthma

There is no cure for asthma, but there are effective ways for people with asthma to manage their condition. This means preventing the onset of symptoms in response to triggers, and controlling symptoms, once they occur.

People with asthma, their family members and their health care providers all play important roles in co-managing asthma. Successful asthma management depends on the following:

• learning about asthma and how to manage it
• avoiding or controlling triggers
• taking the right medicines in the right way at the right time
• ongoing monitoring and follow-up to assess symptoms and response to medication, and to measure lung function
• a personalized asthma management plan

There are two basic types of asthma medicines: "Preventer" medications to decrease the swelling in airways and help prevent asthma episodes. These medicines are inhaled through a device called a "puffer" or inhaler. "Reliever" medications. These are used during an asthma episode or attack to reduce symptoms quickly.

With the right asthma management plan, most people with asthma can lead healthy, active lives.

Minimizing Your Risk

If you (or your child) are diagnosed with asthma:

Work closely with your health care provider to develop an asthma management plan:

• Find out what your specific triggers are, and avoid them whenever possible.
• Use "preventer" and "reliever" medicines as directed by your health care provider. If you have a puffer, make sure you know how to use it properly.
• If you find you need "reliever" medicines more often as time goes on, talk to your health care provider about adjusting your asthma management plan.
• Remember, although asthma symptoms can almost always be controlled, they can also be fatal. Talk to your health care provider about the warning signs that you may need emergency treatment.

Do research and stay current on news about asthma treatment and management.

About the Author

www.hc-sc.gc.ca
Health Canada is the Federal department responsible for helping Canadians maintain and improve their health, while respecting individual choices and circumstances.