Asthma

Asthma is the most common chronic illness seen in childhood, affecting 5 to 15 percent of children in the United States, approximately 3 million children younger than eighteen years of age. One-third of these children have severe asthma. Over the last twenty-five years, there has been an increase in the prevalence of asthma. Although part of this may be attributed to physicians diagnosing asthma earlier in children, there still seems to be a real rise in the number of children worldwide with asthma. In the United States, African-American children are more likely to have asthma and more severe instances of the disease compared to Caucasian children. African-American children under four years of age are hospitalized four times as often for their asthma. Crowded inner city living also has been shown to increase a child's likelihood of having asthma, regardless of race. The inner city environment has particles or allergens such as air pollutants that sensitize these children to develop asthma. Urban settings provide increased allergic exposures and increased viral infections early in life (possibly secondary to earlier daycare placement), and crowding. Furthermore, asthma tends to be more severe among children, resulting in higher death rates for children with asthma. Other associated factors include prematurity, low birthweight, poor nutrition, lack of breastfeeding, and low family income. Genetics also plays a role in developing asthma. If one parent is affected with asthma, the child is three times as likely to develop asthma compared to a child with non-asthmatic parents; if both parents have asthma, the risk increases sixfold.

Asthma is an illness that affects the lungs, specifically the airways. Air enters the body through the nose or mouth. It then enters the trachea, also known as the windpipe. This is the large main airway of the lungs. The trachea then divides into two smaller pipes called bronchi that bring air to both the right and left lungs. These airways then divide into many smaller airways called bronchioles. These small airways eventually bring air (and oxygen) to the smallest sub-unit of the lung called the alveolus. The alveolus is where oxygen enters the blood and where carbon dioxide is released. There are hundreds of thousands of alveoli in each lung.

The airways are made up of three parts. First there are the smooth muscle cells that surround the airway. These cells allow the airway to get bigger or smaller by relaxing or contracting. These muscles are involuntary, meaning that they cannot be consciously moved. They respond to local chemicals and nerves to relax and contract. The second part is the lining of the tube, which is made of normally thin cells called epithelial cells. These cells help to protect the body Children who suffer from asthma use inhalers, or bronchodilators, which allow them to breathe easier. (B. S. I. P./Custom Medical Stock Photo) from particles (such as viruses or bacteria) that may be breathed in but that should not be absorbed into the lungs or the body. The cells do this by trapping particles in mucus and moving them out by a brush border, which acts as a moving carpet by beating and bringing the particle laden mucus back out of the lungs. When the particles get closer to the throat, a person can feel them and is then stimulated to cough to get them out of the lungs. The third part is the lumen, or airway opening through which the air passes on its way to the alveolus to bring oxygen to the lungs (that will then be used by the body). The size of this lumen is affected by the smooth muscle, the lining cells, and by any debris (mucus and particles).

When someone has an acute asthma attack, their airways narrow because of smooth muscles, swelling or edema of the airway lining cells, and production of excessive mucus by these cells, making it more difficult to move air in and out of the lungs. When this happens, the patient will often cough, breathe more quickly than normal, and feel short of breath. People with asthma may also have noisy breathing, or wheezing. Wheezing occurs because the patient must still move the same amount of air through a narrower airway in the same amount of time. This means the air has to move faster to move past these narrow areas. This is heard as wheezing. The process is similar to water flowing through a narrowed pipe or tube; for example, through a nozzle. Water flow becomes noisy and audible, where it is normally quiet. Wheezing, however, may also occur in patients who do not have asthma but may have airway narrowing for other reasons such as a foreign body in the airway. Very young children may wheeze in response to a cold but may not have asthma when they get older. Patients having an asthma attack also can appear to be breathing hard, using extra muscles like their abdomen, shoulders and rib muscles to breathe. If allowed to continue without treatment, a patient will continue to work harder and harder until the muscles of breathing are exhausted, thus leading to death. Patients with asthma may be mildly to severely ill with an asthma attack, and symptoms can progress very quickly if not treated.

Many things can cause asthma attacks. For some people key triggers can be identified. Triggers are environmental, infectious, or social causes that set off a person's asthma. Common triggers include pollens, cigarette smoking, secondhand smoke exposure, dust mites, molds, pet dander, colds, cold air, exercise, stress, and changes in weather. These triggers are sensed by the lungs and the body over-responds, causing an asthma attack. Some patients have asthma where no clear trigger can be identified. Individuals with many allergies are at higher risk for getting asthma. People with eczema (an itchy dry skin condition often associated with allergies) also are more likely to have asthma.

Treatment of asthma requires a whole life approach. Prevention of attacks is extremely important, especially in children with moderate to severe asthma. This requires a multifactorial approach involving attention to and potential changes in all spheres of a child's life, including home and school. Environmental modification includes elimination of triggers such as cigarette smoke, pet dander, dust, molds, pollens, and insects (especially cockroaches). Special care to avoid colds is also important. Furthermore, some children require preventive or prophylactic medicine daily to decrease the number of attacks. These include anti-inflammatory medications in more severe cases of asthma, to help decrease inflammation and swelling of airway lining cells. Once an acute asthma attack has started, treatment consists of albuterol, which immediately relaxes the smooth muscle to help open the airway. Steroids can also increase airway size by decreasing acute inflammation. Oxygen may also be needed. Education of patient, family, and other caregivers in the early recognition of symptoms is key to successful treatment of an asthmatic attack, and improving baseline lung functioning.

Asthma, like any chronic illness, can have a significant impact on a child's psychosocial functioning and development. Children with asthma exhibit a threefold increase in school absences (on average) when compared to children without asthma. A study by Fowler from 1992 also suggests a potential link between asthma and learning disabilities in children with poor to fair health because of severe asthma with poorer school performance. Children with asthma who come from lower income families (household income less than $20,000 per year) were twice as likely to fail a grade than healthy children from low income homes in this study.

Children with asthma also exhibit increased emotional vulnerability. They may demonstrate anxiety regarding their asthma, and feel physically vulnerable as well, sometimes out of proportion to the severity of their asthma. Anxiety with hyperventilation can be a trigger for stress-induced asthma attacks. Young children with moderate to severe asthma may have great fears and anxieties regarding their health and fear of death at a very young age. In addition to the child, parents also develop fear and anxiety in relation to their child with chronic illness, which also may be out of proportion to the severity of the child's asthma. This can lead to increased parental sheltering and over protectiveness, giving rise to the vulnerable child syndrome and feeding the child's anxiety.

Asthma can also be an isolating illness for school-age children. Increased school absences take them away from their friends and peers. Having to leave the classroom to receive medicines or treatments also may give the child a sense of being set apart from peers and therefore different. Furthermore, classmates may perceive the child as being "sick" and may treat him differently as a result, further impairing bonding with peers.

In conclusion, asthma is a common illness among children. It affects their physical, psychosocial, and emotional lives. Effective management involves the child, family, pediatrician, school personnel, and when needed, allergy specialists to minimize symptoms and allow children with asthma to thrive.