Peanut allergy linked to worse asthma in kids

A vendor sells peanuts at the Voi market, 20 km (12.5 miles) south of Hanoi April 17, 2008.

NEW YORK (Reuters Health) - Among children and teenagers with asthma, those who also have peanut allergies may have more or more-severe asthma attacks, a new study suggests.

Researchers found that among 160 5- to 18-year-olds with asthma seen at their center, the 46 with peanut allergies generally had more hospitalizations for asthma exacerbations than children without the food allergy. They also had a higher rate of treatment with oral corticosteroids -- anti-inflammatory drugs given for a short period to control severe asthma symptoms.

Of children and teens with peanut allergy, 23 percent had ever been hospitalized for asthma after the age of 3. That compared with 16 percent of those without peanut allergy.

When it came oral steroids, only 28 percent of kids with peanut allergy had never needed treatment after age 3. That figure was 37 percent among those without the food allergy, according to lead researcher Dr. Alyson Simpson, of Alfred I. duPont Hospital for Children in Wilmington, Delaware.

When she and her colleagues accounted for other factors -- like family history of asthma and any other allergies the children had -- peanut allergy remained linked to higher risks of hospitalizations and oral steroid use.

The goal in children's asthma care is to avoid hospitalizations and oral steroids whenever possible, Simpson noted in an interview with Reuters Health, so any increase in those rates is concerning.

She said that parents of children with both asthma and peanut allergy should be particularly sure to work with their child's doctor to keep the asthma well-controlled. That typically means minimizing kids' exposure to their particular asthma triggers, helping them maintain a healthy weight and, often, giving them medications that prevent asthma attacks.

Simpson and her colleagues report the findings in the Journal of Pediatrics.

Asthma symptoms arise when the airways become inflamed; that inflammation is most commonly triggered by exposure to allergens, such as pollen, mold or animal dander. Food allergies can also spur asthma symptoms.

It is not clear, however, why study patients with peanut allergy tended to have more problems with asthma control, according to Simpson. Her team's findings point to an association between peanut allergy and more asthma exacerbations, but do not prove that the food allergy is the cause.

"The exact link is still being studied," Simpson said.

Understanding the connection is important, she and her colleagues note, as recent studies suggest that both peanut allergy and asthma are on the rise among children -- for reasons that are unclear.

It's estimated that just over 1 percent of U.S. children have peanut allergy, while roughly 9 percent have asthma, according to the American Academy of Asthma, Allergy & Immunology.

SOURCE: Journal of Pediatrics, online February 15, 2010.