The airway muscles may also contract and become narrower. All of these factors make it difficult to breathe.

The person with asthma may cough, wheeze, feel short of breath and have tightness in the chest. In severe asthma attacks, a person might have difficulty talking, have a blue-ish colour on the lips or fingernails. Some people experience a pulling in of the muscles between the ribs or above the breast or collar bones while breathing.

Prevalence

Asthma is a common chronic disease of the airways that’s estimated to affect 300 million people around the world**. In Canada, more than 15 per cent of children ages 4 to 11 have been diagnosed with asthma, and overall the disease affects 2.6 million Canadians*.

In the United States an astounding 34.1** million people have been diagnosed with asthma. For perspective, that happens to be the population of Canada!

Sources:
*PHAC
**AAAAI

What causes asthma?

While it is not completely understood why some people develop asthma while others don’t, your chances of developing the disease appear to hinge on a combination of genetics and the environment.

Key Risk factors:

-Family history. If your parents have asthma, you’re more likely to as well.

-A genetic tendency to be allergic. (This is called atopy.)

-Being exposed to cigarette smoke, either direct or second-hand.

-Living or going to school near air pollution from heavy traffic.

-Exposure to dust mites

-Low-birth weight

-Obesity

-Workplace Exposures*

* Some people develop occupational asthma as adults following prolonged exposures to sensitizing materials in the workplace. (e.g. paint, fumes or dust)

Next Page: Does Asthma Go Away?