Asthma Health Article

United States statistics

Asthma is the most prevalent childhood chronic disease. According to the Centers for Disease Control, approximately 17 million Americans exhibit symptoms of asthma—about five million of those are under the age of 18. More than 50% of asthma cases occur in children between two and 17 years of age. At a younger age, studies indicate that boys are twice as likely to develop asthma than girls. But this imbalance disappears in older age groups.

Asthma is the primary cause of school absenteeism. Asthma is also one of the most prevalent diseases in the workplace. Asthma accounts for approximately three million lost work days for adults and 10.1 million lost school days for children each year in the United States.

According to a recent American Lung Association report, double the number of adult female patients require emergency medical care for their asthma than do adult male patients. It is thought that the differences in male and female hormones may cause this disparity.

In the United States, the mortality rate—number of deaths—attributed to asthma increased 56% from 1979 to 1998. Asthma kills more than 5,000 Americans each year. Doctors believe that most of these fatalities could have been prevented with proper care and treatment.

In general, it is difficult to pinpoint the precise causes of the dramatic increase in asthma cases in the United States. One important factor may be partly due to poor diagnosis and management of individual cases of asthma, especially in less privileged or minority populations. However, after many years of rapid increases in asthma cases, some of the most recent evidence suggests that the number of asthma cases may actually be declining slightly. Further studies will be needed to confirm this trend.

International statistics

Asthma has been described as the fastest growing chronic disease and a world-wide epidemic. Approximately 25,000 children die of asthma each year throughout the world. According to Global Initiative for Asthma (GINA), a world-wide asthma research and education program, there are over 150 million asthmatic individuals worldwide. In most countries, asthmatic cases are increasing 20–50% every decade. Every ten years, asthma claims over one million lives. Some studies have revealed a 75% increase in asthma cases between 1980 and 1994 globally. Children accounted for the greatest increase in numbers.

It is interesting to note that the incidence of asthma varies greatly throughout the world. While about 2% of children in China display symptoms of asthma, approximately 30% of young people in Britain have indications of this disease. In Australia, the incidence of asthma is very high in Caucasian children, but much lower in Aboriginal children.

Why such variations exist in the prevalence of asthma in different populations remains an unsolved mystery. Some scientists speculate that lifestyle factors, such as a lack of physical activity, increased obesity, and more time spent indoors may contribute to higher rates of asthma in more highly developed countries. It is also possible that environmental irritants such as poor indoor and outdoor air quality, along with the presence of potent irritants such as cockroach allergens, may contribute to higher rates of childhood asthma in poorer communities. Other factors that may prompt the onset of asthma are viral respiratory infections, low birth weight, and smaller than average air passageways in asthmatic patients.

Another area of research concerns the connection between common childhood infections and asthma. Many studies have shown that children who are exposed to viruses that cause the common cold and other respiratory infections at a very young age are less likely to develop asthma than their peers living in a more "hygienic" environment. So children living at home with older siblings and those who spend part of their week in daycare centers may be less likely to develop asthma than children who do not interact with others of their own age group.

A related factor could be the overuse of antibiotics. The frequent use of antibiotic medications to treat relatively minor infections may produce changes in a patient's immune system that may increase his or her chance of developing asthma at some point later in life.

Other studies have documented higher rates of childhood asthma in some less advantaged, minority inner city populations in the United States than in wealthier suburban communities. In these populations, exposure to cockroach allergens may be the major culprit.