What kind of children get asthma?
Asthma affects about 5 million children under 18 years of age in the United States and has increased worldwide in recent decades. About half of all cases of asthma develop before the age of 10 years, and another third before the age of 40. Among younger children, asthma develops twice as frequently in boys than in girls, but after the age of 10 years, the number of men and women who get the disease is approximately equal. African American children have a higher risk than Caucasian children, but Hispanic children, particularly those living in poor urban neighborhoods, seem to face the highest risk of the three groups of the population.
In America alone, the risk in children increased by 72.3% between 1982 and 1994. Some European studies attribute this phenomenon to a true increase in cases of asthma but to other factors. A British study indicated that physicians in asthma clinics tend to over-diagnose the disease, and experts who analyzed 16 studies that reported a higher rate of asthma encotraron flaws in the interpretation. They believe that much of the increase is due to greater awareness by parents of the disease and differences in diagnostic criteria. However, another British study indicated that the disease may be under diagnosed in the study, one third of children reported symptoms of asthma had been diagnosed by doctors and were not receiving treatment.
However, other respiratory diseases, sinusitis and oíodo infections are clearly increasing, suggesting that factors airborne elements or environmental factors may be involved.
Theories explaining this remarkable ascent point to improved living conditions in industrialized countries. A recent study found that children in day care are at increased risk of wheezing and infections of the lower respiratory tract. Some studies indicate that the risk of asthma is higher in children under five years who present with wheezing, chest colds are frequently or have a chronic cough, although some experts believe that such infections may actually protect against asthma in the future.
In young children, the wheezing does not necessarily predict asthma. Other scientists believe that because children are now spending three hours or more time per day engaged in sedentary activities, including watching TV, playing video games or using a computer, are overexposed to indoor allergens and asthma contract .
About 75% to 80% of children with asthma have allergies. An Australian study reported that the prevalence of dust mites, an allergen identified, went along with the development of asthma in children between 1978 and 1991.
