A chronic inflammatory disease that makes airways (bronchial tubes) particularly sensitive to irritants, asthma is characterized by difficult breathing. It cannot be cured, though for most patients it can be controlled. This means it's essential to avoid those factors that bother your airways and take the medicines as directed by your doctor.

Now, the difference between a trigger and a cause ...

A trigger sets off an attack, but does not cause your asthma. In other words, the term "trigger" describes those factors that can bring on an attack in someone who already has the disease.

You hear the word "trigger" used incorrectly when someone refers to the dog to which you're allergic as the trigger of your asthma.  Or when they refer to the cat.  Or the mold on the wallpaper as the trigger of your asthma. Or the pollen. Or even house dust mites.  Instead of referring to these as causes, which is what they are, people call them triggers.  You'll hear them say that it's your cat that's triggering your asthma.

This is a bit like calling an approaching car the trigger of an accident.

Demoting causes by calling them triggers tends to make people assume they're not important. They assume that if you just keep using your inhaler instead of making efforts to root out the cause of your asthma and remove it from your environment, you're doing all that needs doing.

This isn't true.  In fact, it's far from the truth.

A cause is something without which an effect (such as asthma) would not happen.  That is ... a cause is something without which you would not be asthmatic. 

We normally think of a trigger factor as something small which causes something big to happen suddenly.  A trigger is a type of cause.  But the bottom line is that the important causes have to be there already if the trigger is to work. That's why the trigger isn't as important to our understanding of the disease.  It's always the cause which underlies the disease that's most important.

For example, if you don't have asthmatic lungs, or your asthma is well-controlled by treatment, a cold will rarely result in asthma symptoms. So in this sense, it's fair to call the cold a trigger factor.  In addition, if you didn't catch a cold, this would not prevent you from having asthma. Which is why it cannot be called a true cause of the disease.

Now, if you have asthma whenever you go near dogs, then dogs in the past have been the cause, and a dog now can trigger an attack.  In other words, a dog can be both a cause of your asthma and a trigger. Concentrating solely on the triggering of the attacks misses the real issue, which is that contact with dogs was a cause of the asthma in the first place.

Obviously, an asthma sufferer will want to avoid both causes and triggers, but the causes are infinitely more serious.  Without the causes, the triggers would do absolutely no harm.

At A Glance

• Asthma is a chronic inflammatory disease that makes airways (bronchial tubes) particularly sensitive to irritants, and this is characterized by difficulty in breathing.
• When talking about diseases, it is important to distinguish between causes and triggers.
• A trigger for asthma is something which sets off an attack, but which does not make you asthmatic in the first place.
• A cause is something without which an effect (such as asthma) will not happen.  That is, a cause is something without which you would not be asthmatic.