 |
ABCs of asthma
It's summer -- and it's asthma season. But then it's always asthma season. As time passes, asthma has grown more intense. The death toll has risen 99 percent since 1979 to 5,167 in 1993. Asthma is the most important chronic disease in children, 4.8 million of whom suffer its symptoms. Overall, an estimated 14.6 million Americans have the disease.
|
| The eight signs of asthma trouble Wheezing, beginning as a slight whistling sound and progressing to a shrill noise with each labored breath. Coughing that gets worse over minutes to hours. Chest skin is sucked in as the patient struggles for air. Breathing out takes longer than inhaling. Breathing is faster. Blue nails and lips, especially in children. Sudden anxiety and apprehension, especially in children. Shortness of breath. Source: American Lung Association Family Guide to Asthma and Allergies. |
Asthma -- a narrowing of airways in the lungs that causes coughing, wheezing and gasping for breath -- has probably been around since cave dwellers slept on furs coated with dust mites and cockroach crud. But why is it on a rampage today when, ironically, we know more than ever about its causes and treatment? "It's a paradox," says N. Franklin Adkinson, professor of medicine at the Johns Hopkins Medical Institutions. "After over a decade of spending large amounts of money investigating this disease, and finding more powerful, less toxic drugs, all of which should benefit patients, the prevalence has doubled" and the death rate has soared. Consider the 300 million air sacs in the human lungs: Small, fragile, exquisitely designed, they are a critical place where body meets world. The goal, naturally, is to exchange gases: Oxygen from incoming air is transferred to the bloodstream. |
| Medical plug: Asthma is definitely not a do-it-yourself illness. Nor is it something that should be treated only in emergency rooms. Above are some asthma signs and symptoms. If you suspect you have asthma, don't call The Why Files. Call your doc.
In a normal bronchial tube, relaxed muscles and thin walls allow good airflow. In an inflamed tube, tightened muscles, thickened walls, and abundant mucus inhibit air flow. Source: American Lung Association. |
And carbon dioxide and other waste gases in the blood leave with the exhaled air. This gas exchange is the kind of thing you take for granted until it goes bad.
In asthma, that deterioration starts when the lung becomes what doctors call "hyper-reactive." Essentially, that means the airways respond too strongly to a stimulus by narrowing. Breathing becomes more difficult; in severe cases, it becomes impossible, and the disease claims another victim. Typically, asthma occurs in episodes. The sequence starts with an inflammation, often caused by an allergic response to dust mites, animal dandruff, mold or pollen. That inflammation sets the stage for further irritation. "If your airway is provoked by an allergen, then any other allergen will have a greater effect," says Norman Edelman, a lung specialist who is a consultant to the American Lung Association and dean of the Medical School at State University of New York at Stony Brook. As the series of action-hyper-reaction continues, any of three processes reduce the effective size of small air passages in the lung:
Combined, this narrowing makes breathing, particularly exhaling, more difficult. In more severe attacks, wheezing and whistling are heard. To the asthmatic, it can feel like breathing through a straw. So tell the truth: How bad is asthma? The Why Files Staff: Terry Devitt, editor; Darrell Schulte, webmaster; Dave Tenenbaum, feature writer; Susan Trebach, team leader |
|
 |
 |
 |
The passage lining swells