What is Asthma?
Asthma is a common condition in childhood. In the United States, 10% to 15% of children in grade school have or have had asthma. The number of children with asthma is increasing, and the amount of illness due to asthma may also be increasing in some parts of the country. The reasons for these increases are not exactly known; however, outdoor air pollution and increased exposure to allergens are not likely causes.
Asthma is a chronic disease of the tubes that carry air to the lungs. These airways become narrow and their linings become swollen, irritated, and inflamed. In patients with asthma, the airways are always irritated and inflamed, even though symptoms are not always present. When the airways are hyper-reactive, they can go into spasms, causing blockage and symptoms of wheezing, chest tightness, and shortness of breath.
Children with asthma can have symptoms start or worsen when they are exposed to many indoor substances such as:
- Dust and dust mites
- Animals such as cats and dogs
- Molds - especially El Paso mold
- Secondhand cigarette smoke
Children with asthma may also be sensitive to colds and other viral infections, cold air, and particles or chemicals in the air. Ongoing exposures to these substances will not only worsen asthma symptoms, but also continue to aggravate airway inflammation. Recognizing and knowing the causes and triggers for asthma can allow families to reduce or avoid these triggers and reduce ongoing airway inflammation and hyperreactivity. This can reduce the severity and frequency of asthma symptoms and, hopefully, the need for as much asthma medication.
Studies have shown that a child’s exposure to infections early in life can determine whether he develops allergies or asthma. Some infections seem to decrease the risk of developing asthma, whereas one infection, respiratory syncytial virus, increases the risk.
After confirming an asthma diagnosis, your pediatrician will grade the severity of your child’s condition. This grading takes into account the frequency and severity of past and current asthma symptoms and the physical examination, and may include measures of lung function including spirometry or peak flow measurements. This information enables your pediatrician to select the right medication and determine the proper dose to keep the condition in check. In making a decision about a child’s asthma severity level, the first distinction to be made is whether your child has intermittent asthma (ie, just occasional problems) or persistent asthma (ie, more than occasional). Patients with persistent asthma can have mild, moderate, or severe asthma.
A child who has symptoms of wheezing and coughing no more than 2 days a week is considered to have intermittent asthma; nighttime flare-ups occur twice a month at most. Outside of these few episodes, a child with intermittent asthma is free of asthma symptoms.
Any child with asthma symptoms more often than 2 days a week or 2 nights per month, on average, is felt to no longer have intermittent asthma but persistent asthma. Prevention is key with persistent asthma; both by avoiding triggers and daily medication (an inhaled steroid and allergy medications). Persistent asthma has 3 levels of severity.
Mild Persistent Asthma
In mild persistent asthma, symptoms occur more than twice a week but less than once a day, and flare-ups may affect activity. Nighttime flare-ups occur more often than twice a month but less than once a week. Lung function is 80% of normal or greater.
Moderate Persistent Asthma
Asthma is classified as moderate persistent if symptoms occur daily. Flare-ups occur and usually last several days. Coughing and wheezing may disrupt the child’s normal activities and make it difficult to sleep. Nighttime flare-ups may occur more than once a week. In moderate persistent asthma, lung function is roughly between 60% and 80% of normal, without treatment.
Severe Persistent Asthma
With severe persistent asthma, symptoms occur daily and often. They also frequently curtail the child’s activities or disrupt his sleep. Lung function is less than 60% of the normal level without treatment. Severe is the least-common asthma level.