Allergy and Asthma - Part II

Asthma is best described as a genetically-determined, reversible over-reactivity of the small bronchial airways of the lung. This hyper-irritability results in chemical reactions (as described under allergy in Part I of this article) in the lung tissue which lead to spasm of the smooth muscles encircling the airway, swelling of the lung tissues, and increased mucus production. The consequences are narrowing of the airway which restricts mainly the exhalation of air, trapping air in the lung and reducing the exchange of oxygen and carbon dioxide, i.e., “shortness of breath.”

There are really two forms of asthma: allergic and non-allergic. The allergic form results from the same allergy process in the upper airway as described in Part I of this article. The non-allergic form results from hyper-irritability of the lung tissue but is set off by agents such as dry air, cold air, pollutants, fumes, smoke, and strong odors. An associated phenomenon is E.I.B. (exercise-induced bronchospasm), also called E.I.A. (exercise induced asthma). EIB is not the same as asthma but does occur in patients with allergic and non-allergic asthma. EIB also occurs in allergic patients who do not have asthma. EIB is felt to be spasm of the smooth muscle around the bronchial tubes, coming from inhalation of dry, cold, or polluted air during mouth breathing.

The symptoms of asthma and EIB are varied and sometimes subtle. The obvious ones are wheezing and shortness of breath. Subtler are cough (especially at night), chest tightness, decreased exercise tolerance and performance, waking at night, chest pain, fatigue, decreased appetite, and heartburn.
The diagnosis is made from evaluation of the history, physical exam, and sometimes specialized tests. The history of family allergies and asthma, a history of "chronic or recurrent bronchitis” in a young person (< 30 years old), or a history of eczema or allergic rhinitis in association with symptoms are all highly suggestive. If the symptoms are found associated with reversible wheezing by exam, this is very likely asthma. There are other causes of wheezing so further tests may be needed. Other tests might include allergy tests, spirometry ( a measure of lung volumes and function), x-rays, and the like.

Treatment, as noted for allergic rhinitis in Part I of this article, is both specific (directed at allergens or triggers) and general (directed at the chemical reactions). Specific measures are those directed at avoiding allergens or triggers; these would include warm filtered air, masks, and the like. Immunotherapy (“allergy shots”) is used for patients with allergic asthma who do not respond well enough to standard medicines and have severe attacks.

General treatment is applicable to allergic or non-allergic asthma as well as EIB. There are two levels of treatment: rescue and controller. The rescue medicines are primarily short-duration, quick-acting inhaled bronchodilators such as albuterol. When symptoms occur, these are used to provide “rescue” (relief from wheezing) in 10 - 20 minutes. On occasion, injections of adrenalin may be used in the ER or doctor’s office. The rescue medications can also be used as a preventive in EIB, usually inhaled 10 - 15 minutes before exercise and are effective for about 4 hours. Oral corticosteroids are also used occasionally for 3 - 5 days to bolster rescue medicines in more severe attacks.

In asthma sufferers who have more frequent, more severe asthma attacks, it is necessary to use “controller” drugs to prevent occurrence of these attacks. Although the particular ones used is a decision to made in conjunction with your doctor, I will briefly cover what is available so you can better discuss the possibilities with your doctor.

Although not directly effective in asthma, antihistamines and nasal allergy treatments such as nasal steroids may be considered a part of asthma treatment. The reasoning is as follows: in allergic patients, when allergic rhinitis is active, two problems result. One is the difficulty of breathing through the nose, forcing mouth-breathing which brings drier, less filtered, colder air directly to the lungs. The second is the interaction of the upper and lower respiratory tract--when there is chemical release from the upper respiratory tissues, the lung becomes more reactive to allergens and triggers. So good control of the nasal aspect of allergy is beneficial to the allergic asthma sufferer.

There are a number of asthma controller medications available. Controller medicines are not to be used for “rescue.” The most effective and commonly used are the inhaled corticosteroids used 1 - 2 times a day. Also effective and often used are the slower-onset but long-acting inhaled bronchodilators (e.g., fomoterol, salbuterol) which prevent or reduce bronchospasm when used twice a day. Cromolyn sodium is an older inhaled drug that is effective but must be used 4 times a day regularly. There are several leukotriene (one of the chemical mediators in allergy) blocking drugs (e.g., Singulair®) which are most often prescribed in combination with corticosteroids and/or long-acting bronchodilators. Another drug used as an adjunct to other controllers is inhaled ipatropium. Ipatropium is also used on occasion as an adjunct to rescue inhalers. Theophylline preparations are an old class of drugs that are still occasionally used although they are not as effective as inhaled corticosteroids and long-acting bronchodilators and do have some troublesome side effects.

Although there are many effective treatments, an important measure in dealing with asthma is monitoring your control effectiveness. This is because the inflammation of the lung tissues can smolder for a time without producing overt symptoms, setting the stage for a more severe attack when it occurs. Two commonly used means of monitoring are peak flow meters and the “Rule of Twos.” Although spirometry can be used as well, it is a more expensive and complicated measure, not suitable for day-to-day use. A peak flow meter is a simple way to measure the ability to exhale rapidly and can be done multiple times a day as needed. In practice, an asthma sufferer can establish what their own “personal best” peak flow is while in good control and then measure the peak flow from time to time while not symptomatic as well as when symptomatic. This will allow altering the treatments to prevent attacks.

The Rule of Twos is another useful way of monitoring whether control is adequate. If you have to use rescue medicines more than 2 times a week (excluding the use before exercise if you have EIB), if you are waking with asthma symptoms more than 2 times a month, if you are filling your rescue inhaler more than 2 times a year, or if your peak flow drops by 2 times 10% (20%) from your usual, you are not in good control and should be discussing changes in your medicines with your doctor.

Some asthma sufferers will do better with breathing exercises provided through a respiratory therapist. Maintaining general aerobic fitness helps you deal with asthma more successfully.
Using all the tools available, roller derby and asthma can still be a successful combination, and you can skate through your asthma well.