Asthma is a medical illness that affects the airways of the lungs caused by chronic inflammation of breathing passages known as bronchioles. Asthma is a common disease, affecting 17 million Americans and as of 2010, more than 300 million worldwide. Asthma causes $13 billion each year in lost productivity to the U. S. economy. Approximately 5,000 people die annually in this country from asthma and 250,000 worldwide.
The exact cause of asthma is not known, but what is known is that people with asthma have chronic airway inflammation with excessive airway sensitivity to certain triggers that will induce an asthma attack. An asthma attack occurs because of an allergic reaction by the body’s immune system to an “invader.” When the cells of the immune system sense an invader, they set off a series of reactions that fight the invader, which results in spasming of the lung bronchioles and mucous production.
Invaders are triggers that set off the asthma and vary among individuals. Some triggers include: tobacco or wood smoke exposure, pollution, perfumes, cleaning products, workplace irritants, molds, dust, upper airway infection, cold weather, stress, exercise, acid reflux, sulfites in food and wine, or hormone changes as seen in menstruation. Risk factors for developing asthma can be tied to hay fever, eczema and genetic predisposition as in a first-degree relative.
Common symptoms of asthma include wheezing, shortness of breath, chest tightness and coughing. Acid reflux coexists in 80 percent of patients with asthma. One theory is that the presence of chronic acid aspiration from the reflux promotes bronchoconstriction of the lung airways. An abnormal anatomy such as increased fatty tissue in the upper airway or an altered skeletal anatomy of the back of the throat will result in apneic spells and restless sleep.
There are three basic measurements to determine how well a person is breathing. The spirometer is a device that determines how much air you can exhale and how forcefully you can breathe out. This test is generally done before and after the patient uses their inhaler. The peak flow meter also measures how forcefully one can breathe out during an attack. Lastly, the gold standard for determining how well the patient is getting oxygen into their bloodstream is the oximetry reading, which involves a painless probe called an oximeter placed on one’s finger and measures the amount of oxygen and carbon dioxide present in the body.
Various options are available for the medical treatment of asthma and are used to minimize the inflammation that will cause an acute asthmatic attack. The first is a long acting beta agonist. This class of drugs is chemically related to adrenaline and is generally administered by way of an MDI, or metered dose inhaler. The MDI delivers a standard dose of medication with each puff.
Steroids will reduce inflammation and open the airways. Steroids can be given orally, intravenously or through an MDI. Methylxanthines such as theophylline and aminophylline were more common years ago, but their chemical relation to caffeine puts the patient at risk to side effects. It is not uncommon for an asthma patient to drink a cup of caffeinated coffee or tea and notice an improvement in their airway breathing.
Leukotrienes are chemical substances that promote the inflammatory response seen in acute asthma attacks. The function of leukotriene inhibitors is to block these chemicals and inhibit the inflammation. They are used second line in cases where the asthma is not severe enough to require steroids.
“Exercise-induced asthma” is a real occurrence. Athletes will use an MDI with Cromolyn Sodium, which prevents the release of agents that induce asthma-related inflammation. This is generally done 30 minutes before exercise.
Next time you see smog, hold your nose and head the other way. Your lungs will thank you.
Dr. Ballard is a Board Certified Internist and Geriatrician with a special interest in Women’s Health. She practices in Enumclaw, 360-825-1389. Dr. Ballard’s comments are informational only and not to be construed as medical advice. Consult your personal physician for any medical issues.