Asthma affects 5-8% of the population, including nearly 5 million children. Physicians use words such as bronchial asthma, asthmatic bronchitis, and reactive airways disease to describe their patient’s condition. The airways narrow and swell with mucus causing wheeze, cough, shortness of breath, and chest tightness. Symptoms occur as infrequently as a few times a year with a cold or as often as every day. Unlike other lung diseases such as emphysema, the airway obstruction in asthma is reversible with the use of medication, allowing most patients to have totally normal lung function when their asthma is properly treated.
Who gets asthma?
Asthma can develop at any time in one’s life. In children and young adults, asthma is an allergic disease in greater than 90% of cases, often accompanied by other allergies such as hay fever, eczema, and food allergies. There is a strong hereditary component with offspring with one allergic parent having a 30-50% chance of having allergies and those with both parents being allergic having 60-80% likelihood of developing allergies. In people who develop asthma after age 40, allergies are not as often responsible for their disease (about half of these patients have allergies).
How do allergies cause asthma?
Inhaling airborne allergens (pollens, molds, animal dander, and dust contaminants) sets off a cascade of cellular events that produce narrowing (lung muscle spasm) and swelling (inflammation) of the bronchial tubes. An asthmatic with a positive skin test to ragweed, for example, will begin wheezing within 10 minutes of breathing ragweed pollen in the research laboratory. Nearly all allergic asthmatics will have nasal symptoms along with their asthma as the pollen heading for the lungs deposits on the nasal lining. Once the nose is swollen and congested it can no longer function as a filter, air conditioner, and humidifier for the lungs, making asthma worse. Other things that can trigger asthma symptoms besides allergens include viral infections, exercise, cold air, pollution, smoke, and laughing.
How is asthma diagnosed?
There is no single laboratory test for asthma like there is for other diseases. The physician must take into consideration the symptoms described by the patient, things that trigger symptoms, time of year they occur, previous response to therapy, environmental history, family history, and lung function testing. In the rare difficult to diagnose patient, a methacholine inhalation study may be helpful in detecting asthma.
What makes asthma worse?
This is the question that should be asked when asthma worsens. It is preferable to eliminate the cause of worsening asthma rather than add more medicines to control the breathing. Some of the common causes of increasing asthma include increased allergen exposure (e.g. new cat, cleaning dusty closet, pollen season), chronic sinus infection, viral infection, gastroesophageal reflux (regurgitation of stomach acid up the food pipe), and improper use of inhaled medicines.
Is there any warning of an asthma attack?
Asthma attacks can come on suddenly, but more often than not there are warning signs of worsening asthma. By properly recognizing these warnings you can adjust your medications according to an “action plan” provided by your doctor to ward off a serious attack. The common warning signs to be on the lookout for include:
- increasing need of bronchodilator inhaler (albuterol, Proventil, Ventolin, Maxair),
- inhaler effective for less than usual 6 hours,
- waking up at night with cough, wheezing or chest tightness,
- flu or upper respiratory infection,
- fall in normal peak flow measurements.
If you are not sure as to the proper steps to take in response to these warnings, please call your doctor before it becomes too late.