Nearly five million children in the United States have asthma , which causes coughing, wheezing, and shortness of breath. These symptoms are due to chronically inflamed airways that overreact to “trigger” factors—cold air, cigarette smoke, viral infections, exercise, and allergens (mold, animal dander, etc.).

Asthma symptoms appear early in life; the majority of children are diagnosed by age five. Treatment, which is often delivered directly into the lungs with an inhaler, takes a two-pronged approach: long-term medications to reduce the number and severity of attacks and short-term medications to treat an acute attack. Now, researchers are investigating if corticosteroids—given early enough in life—can prevent the development of asthma in high-risk children (those with frequent wheezing or allergies, and/or a parent with asthma).

In previous studies of school-aged children, corticosteroids did not prevent asthma. However, the drugs may have been given too late to be effective. Researchers studied younger children (aged 2-3) in the Prevention of Early Asthma in Kids (PEAK) trial. Their research, in the May 11, 2006 issue of the New England Journal of Medicine , found that two years of treatment with inhaled corticosteroids did not prevent the development of asthma among this group of high-risk children.

About the Study

The PEAK trial included 285 children who were 2-3 years old and at high-risk for developing asthma. For two years, half of the children were given two puffs per day of the inhaled corticosteroid fluticasone propionate (Flovent) and the other half were given placebo. During the third year, called the observation year, daily puffs were stopped and the children were monitored. Researchers compared the number of days without wheezing during the observation year between the corticosteroid group and the placebo group.

During the observation year, the number of wheeze-free days was the same in the placebo and corticosteroid groups. During the treatment years, children given corticosteroids had significantly fewer symptoms, but slower growth than those in the placebo group. This growth disparity was resolved by the end of the observation year.

How Does This Affect You?

According to the PEAK study, corticosteroids can effectively treat wheezing, but cannot prevent development of asthma among high-risk, preschool-aged children. Authors of another study in the same issue of the New England Journal of Medicine theorized that corticosteroids need to be given even earlier—during infancy—to affect the development of asthma.

The Prevention of Asthma in Children (PAC) trial studied infants whose mothers have asthma. When the infants experienced wheezing, they were treated with either inhaled corticosteroids or placebo. After monitoring these children until age three, the PAC researchers found that corticosteroids failed to provide any benefit; these drugs did not help children recover quicker from wheezing episodes, and did not prevent disease progression.

While corticosteroids have a role in treating asthma, they should not be used with the intent of prevention, as there are no proven benefits and there is a possibility that these drugs may interfere with growth (but not irreversibly).

Although asthma cannot be prevented or cured, it can be controlled so that children with asthma can participate fully in school and recreation. If your child is at risk for asthma or has been diagnosed, talk with your child's doctor about the best course of treatment. Take steps to minimize your child’s trigger factors and carefully monitor symptoms. Develop a disease management plan for your child that includes safe participation in exercise, which can improve airway function.