new study, published in the June issue of Pediatrics,
also found that the cost of asthma as a result of these
residential exposures in older children and adolescents
was more than $400 million a year. Taken together with
the previous study, the cost of asthma due to residential
exposures among all children and adolescents exceeds
$800 million a year. Asthma's medical costs included
clinic and emergency department visits, hospital outpatient
services, hospitalization, medications, loss of work
as a result of school absence, and illness days.
elimination of residential risk factors, if causally
associated with asthma, would have a profound effect
on medical costs of asthma and, more importantly, on
the health of children," says Bruce Lanphear, M.D.,
M.P.H., associate professor of pediatrics at Cincinnati
Children's and the study's main author.
is the most common chronic illness of childhood, estimated
to affect more than 4 million children in the United
States. From 1980-93, the prevalence of asthma increased
by 75 percent, primarily in children younger than 5.
year, asthma leads to more than 3 million clinic visits;
550,000 emergency visits; 150,000 hospitalizations;
and more than 150 deaths in children younger than 15.
have identified several residential risk factors for
childhood asthma, including allergies to pets, environmental
tobacco smoke, dust mites and cockroaches. Because risk
factors vary by geography, urbanization and poverty,
the contribution of housing factors to asthma in children
in the United States has been unclear.
Lanphear studied 5,384 children and adolescents who
participated in a survey between 1988 and 1994. The
children participated in the National Health and Nutrition
Examination Survey III, a survey of the health and nutritional
status of children and adults in the U.S. Overall, 11.4
percent of the children had doctor-diagnosed asthma.
This extrapolates to 4.6 million children and adolescents
in the United States with asthma.
appear to be the major risk factor," says Dr. Lanphear.
"Children and adolescents who had a history of allergies
to a pet were 2.4 times more likely to have doctor-diagnosed
asthma. More than 330,000 excess cases of asthma were
attributable to having a pet allergy. Parents need to
consider carefully the risks and benefits of owning
study is also the first to estimate on a national level
the number of cases of asthma linked to allergic response
to specific indoor allergens, such as dust mites and
cockroaches. About 520,000 excess cases were due to
dust mites, and about 375,000 to cockroaches.
together, these and other data demonstrate that children's
health is inextricably linked with housing," says Dr.
Lanphear. "The contribution of environmental risk factors
to asthma is considerably larger than family history
or heredity. Unfortunately, despite growing evidence
that residential exposures have a dramatic impact on
children's health, housing is largely ignored as a public