A brief guide to understanding asthma

This chronic respiratory disease strikes an estimated three million Canadians. The good news is that self-monitoring, medications, and sensible lifestyle changes let most people lead active, healthy lives.

The word "asthma" comes from the ancient Greek for panting. However, wheezing, coughing and tightness of the chest are the most common asthma symptoms. Exactly what causes this disease is unclear, but genetics, allergies and environmental factors are believed to play key roles.

• When you have asthma, your immune system overreacts to tiny substances in the environment and treats these usually harmless materials as deadly invaders. This triggers a full-scale alarm in your respiratory system. Immune system defenders called mast cells, located in tiny passageways in your lungs, unleash a barrage of histamines and other chemicals. Your airways then become inflamed and constricted, and your breathing tubes produce extra mucus, making it even more difficult for air to get through.
• An asthma attack can last for minutes or hours. It may come on gradually or suddenly, and it can strike day or night. Asthma runs in the families of about one-third of those with the disease. About half of all cases start in children under age 10, but the disease can occur at any age. Patterns vary greatly from one person to the next, so it’s important to learn what your triggers are and how your body reacts.

• Use an inhaled bronchodilator to open airways. Always keep one on hand in case of a severe attack.
• Use a peak flow meter to help you gauge when an attack is coming.
• Take preventive anti-inflammatory medications to lessen the frequency and severity of attacks.
• Learn your signs and symptoms. Knowledge of your triggers enables you to avoid them.
• Get a pneumonia vaccine or annual flu shot to prevent respiratory infections.

• Perform at your peak. A peak flow meter can help you head off an asthma attack before it becomes serious. This simple and inexpensive plastic gadget measures how fast you can exhale air from your lungs. People with untreated asthma have low "peak flow," which increases (often dramatically) within a few minutes after medication. Measure your peak flow twice a day when your asthma is under control to establish what’s normal for you. With this baseline reading, you'll know when the readings begin to fall, possibly signalling an attack.
• Give yourself a spacer. A metered-dose inhaler, the most common type, lets out a burst of medication when you press down on it. But it can be tricky to time correctly. A special device called a spacer may help. This long plastic tube attaches to one end of the inhaler; the other goes into your mouth. Once the inhaler is activated, the medication remains in the spacer until you inhale it. With some, the metered dose is released only when you breathe in.
• Clean house. Up to 90 percent of people with asthma react badly to dust mites. Solutions include banishing carpets, dusting religiously with a wet or oiled cloth and using a vacuum with a microfiltration bag. Wash all bedding in hot water (54°C/130°F or higher) once a week, and consider using shades instead of dust-catching blinds or curtains.

• The Asthma Society of Canada (1-800-787-3880) offers all the latest research and tips on how to cope with and take control of asthma on their comprehensive website at www.asthma.ca.
• Children with asthma can become "Asthma Agents" online at www.asthmakids.ca.

Asthma can be a tough condition to live with. If you think you suffer from the ailment, confirm the diagnosis with a doctor and start making lifestyle changes to help. With a few simple changes, you can live an active, healthy life.