Aging Begins at 30

What Is Asthma?

The Greeks gave it the name asthma meaning panting. There are three main symptoms: difficult breathing, cough and wheezing. The cause is twitchy lung tube muscles with swelling of the tube lining and the production of a sticky mucus that strings out on Kleenex like tapioca. These things narrow the lung tubes (bronchioles) make silent breathing a whistling, snoring wheeze or rhonchus. Asthma is worse at night, causing you to wake up coughing at 3:00 AM. Nobody knows why. It is an episodic disease, acute attacks being interspersed with symptom-free periods.

Under the microscope the lung is inflamed with two marker cells, the eosinophil and the mast cells. Both belong to the white blood. One has granules that stain pink named eosinophils after the Dawn Goddess Eos. The other likes basic methylene blue and stains purple (basophilic). The cells contain histamine and trienes leukotrines (white cell, triple-bonded chemicals) that loosen cell joins and allow foreign proteins to enter deeply and cause lung tube spasm.

There are groups of asthmatic patients. First are families who have hay fever and asthma caused by an abnormal immunoglobulin in the blood called IgE. These asthmatics tend to get lung tube spasm from inhalants such as, animal danders, dust, and molds (diagnosed by skin tests). Their asthma is episodic and comes on when pollens or molds from wet leaves are airborne. Asthma developing late in life tends to be nonallergic without positive skin tests.

Another group of asthmatics (who have nasal swellings called polyps and inflamed sinuses) may react to aspirin or NSAID drugs such as ibuprofen or to a close relative of aspirin called tartrazine yellow food dye.

Exposure to industrial pollutants like sulfur dioxide during thermal inversions makes all kinds of asthma worse but possibly can cause asthma newly in people without lung disease. Smoking does the same thing. Baker's asthma caused by reaction to wheat flour is one of a family of occupational asthmas including woodworkers, photographers, metal workers, solderers, farmers, plasticiser's, and printers asthma. A weekend free of asthma suggests occupational asthma. This is less obvious in hobby workers asthma.

Influenza or rhinovirus (common cold) infections in adults or respiratory syncytial or other viruses in young children can exacerbate or lead to asthma. The viruses probably loosen the tight junction between lung tube lining cells and allow allergens to trigger bronchial muscle spasm.

Exercise can start an attack of asthma. Dry cold air, in cross-country skiing, is much more provocative than warm wet air from indoor swimming. Emotions can influence asthma (already present from other causes) in some patients and not others or in one episode and not another.

Remember asthma blocks lung tubes and the air sacs are normal. Emphysema (smoker's lung) destroys air sacs and the tubes are usually normal, a bad combination in smoking asthmatics

Asthma can start at any age. It affects 3% of the U.S. population. About one-half of the cases develop before age 10 and another third before 40. About 4% occur in the elderly. Most deaths in asthma occur over the age of 55, but life expectancy is normal. It is the only chronic disease, apart from AIDS and tuberculosis, that is on the rise throughout the world.

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See related Patient Topics Asthma, Breathing Problems, Immune System/AIDS, Lungs and Breathing or Symptoms and Manifestations.

See related Provider Topics Asthma, Breathing Problems, Immune System/AIDS, Lungs and Breathing or Symptoms and Manifestations.

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