What is asthma?
Asthma is a chronic lung (respiratory) condition. From a patient’s perspective, it is characterized by symptoms of varying intensity and frequency. Asthma symptoms are related to the lungs and to breathing. Some people with asthma have very mild disease and have no symptoms for much of the year. Individuals whose asthma is at the other end of the asthma spectrum may require several daily lung medications taken on a regular basis in order to normalize lung function and attain a symptom-free state.
In its most severe “life-threatening” manifestation, asthma can be responsible for recurrent hospitalizations, severely compromised quality of life, and even death. Physicians who specialize in asthma care firmly believe that even the most severely affected asthma sufferers can be successfully treated. With proper medical care and cooperation between patient and physician, asthmatics should lead a full and satisfying life.
Is it true that asthma is on the upswing?
Yes, there are more “cases” of asthma now than ever before in the United States. The prevalence of asthma is increasing in other industrialized countries worldwide as well. Prevalence is the total number of cases of a disease in a population at any given point in time. Of great concern to physicians are urban neighborhoods, such as parts of Harlem and of the South Bronx in New York City, where asthma in children has become epidemic and represents a health crisis.
Is asthma more common in urban than rural areas? Environmental factors are very important in the city, but many of the “triggers” that plague urban environments may also be found in rural areas, such as volatile organic compounds (found in varnishes, aerosol sprays, household disinfectants, and similar products), peeling paint, mold, decaying wood in older buildings, not to mention the heavy smoke from those romantic’ wood fires that vacationers love to build when they go to the country. My own childhood was spent in a small Midwestern town with no significant heavy industry or other causes of environmental pollution, yet it was marked for me by an annual parade of seasonal allergies, colds, and a perpetual wheezing “croup.”
Why is asthma so common ?
Asthma is very common, affecting approximately 1 of every 10 Americans at some point in their life, according to 2001 data from the CDC’s National Health Interview Survey. It is not clear why asthma has become such a prevalent chronic condition. One theory holds that physicians have become more adept at diagnosing asthma correctly so that the more precise identification and more accurate counting of asthmatics has lead to a perceived increase in diagnosed cases of asthma.
Unfortunately, the opposite is true: The diagnosis of asthma is too often overlooked, particularly in older age groups and in adolescents, especially teenage girls. The fact is that asthma has truly become more common. A more likely theory implicates various environmental factors. Smoking, for example, became socially acceptable for women after World War II. Infants of mothers who smoke are at risk for the development of wheezing and asthma in childhood. Increasing air pollutants and particulates found in urban or industrial areas may also play an important role. From the perspective of an asthma specialist, the enactment of anti-smoking laws banning smoking in all indoor public places, such as in New York City, is a crucial step toward improving air quality for all.
Asthma is a disease of children, isn’t it?
Asthma is frequently diagnosed in children and is the most common chronic disease of childhood. Asthma, however, is not simply a disease of childhood. Asthma affects adults as well. Many asthmatics are diagnosed well into adulthood. Although some adults with asthma may previously have experienced asthma as a child, others develop the condition for the first time as an adult. Asthma can thus develop at any age.
Asthma is not simply a disease of childhood.
Do lungs continue to develop after birth?
Yes. Humans’ lungs continue to grow and develop after birth. The specialized gas-exchanging lung units called alveoli, where oxygen is exchanged for carbon dioxide, develop postnatally. In fact, the majority of the lung alveoli — nearly 85% — are formed after birth, during the first three years of life. The blood supply within the capillary network matures in parallel with alveolar development from birth to 3 years of age. Mucus cells also develop after birth.
Because the majority of alveoli develop postnatally, the first three years of life can be viewed as a potentially vulnerable period. Young children afflicted with severe pneumonia or tuberculosis during alveolar development, especially in the pre-antibiotic era, for example, were left with some degree of pulmonary impairment. Similarly, it is crucial that babies and young children be raised in cigarette and smoke-free homes to maximize normal lung maturation.
After the age of three, the lungs are basically formed, but not fully grown. As our bodies grow through adolescence to adulthood, so too do our lungs. Adolescence represents a second “vulnerable” window. Recent scientific studies indicate that teenagers who smoke are left with lung function that is less than predicted when compared to healthy nonsmoking teens. The finding of stunted lung function development in adolescent smokers is especially notable in girls.
Do allergies cause asthma?
The answer depends on what you mean by “cause.” On one hand, the condition we call “asthma” is a disease that is different from allergy. On the other hand, allergies and asthma frequently coexist in a given individual. An individual with significant allergies is more and asthma likely to also carry a diagnosis of asthma than someone frequently without any allergies. Specific allergies can also be a coexist in a type of external trigger for asthma exacerbations and given increasing symptoms. For example, a child with asthma individual. Who is also allergic to cats will likely develop symptoms of his asthma if exposed to cats. For that child, cat exposure will worsen asthma, but it won’t cause it.
The most severe form of an allergic reaction is called anaphylaxis. An anaphylactic reaction, especially if untreated, can involve the respiratory system and the lungs. It leads to bronchospasm and narrowed airways, with edema or swelling of the air passages. The anaphylactic allergic response can cause wheezing, cough, and difficulty breathing — symptoms indistinguishable from asthma. An anaphylactic reaction can occur in response to many agents, including bee venom and certain medications. It is considered a true medical emergency because it is potentially life threatening.