HEALTH
From Issue #5
Asthma
An asthma
attack begins when an external or internal stimulus (such as cigarette
smoke, cold air, or a respiratory infection) triggers a spasm in
the smooth muscle layer of the airways in the lungs. The spasm causes
the airways to constrict and leads to inflammation in the mucosa
- the mucus-producing tissue that lines the airways. The mucosa
swells and begins to secrete mucus, leading to further narrowing
of the airways and greater obstruction of airflow. Coughing, wheezing,
and gasping for breath are your body's way of trying to clear your
airways and bring more air into your lungs.
Allergies are to blame in about 50% to 70% of adults with asthma.
In so-called, "allergic asthma," when an allergy-producing
substance (allergen) enters the lungs, it attaches to an antibody
on specialized cells (called mast cells) in the airways. This,
in turn, sets off a series of biochemical events that lead to
airway constriction. As a result, allergy testing is often an
important part of a diagnostic work-up for asthma. Stress also
appears to contribute to airway reactivity and may worsen an asthma
attack.
Exercise can bring on wheezing, coughing, and shortness of breath
among people who don't otherwise have asthma. In fact, about 10%
to 15% of the general population has asthma symptoms during exercise.
And up to 90% of people diagnosed with asthma experience attacks
during intense physical activity. The problem is especially common
in the fall and winter months, when cold, dry air triggers airway
constriction. If possible, try exercising indoors during the colder
months of the year. Warm, humid air - and inhaling steam -- can
help prevent airway reactions.
