Many of those suffering from the allergies are also experiencing reactions more often and with more severity than researchers expected.
That's according to a new study from a group that included scientists from the University of Arkansas for Medical Sciences (UAMS) and the Arkansas Children's Hospital Research Institute (ACHRI).
The multi-year study following children across the nation also found that when severe and potentially life-threatening reactions occurred, some caregivers were hesitant to give children epinephrine, a medication that reverses the symptoms and can save lives.
"The results are troubling, especially since these children had known food allergies and the parents and caregivers received extensive follow up and still most of them had an allergic reaction and the majority of them had more than one in a given year," said study co-author Stacie M. Jones, M.D., professor of pediatrics in the UAMS College of Medicine and chief of the Pediatric Allergy and Immunology Section, who holds the Dr. and Mrs. Leeman King chair in Pediatric Allergy.
The study results appear online in the June 25 issue of Pediatrics (http://pediatrics.aappublications.org/) and are the latest findings from the Consortium of Food Allergy Research (CoFAR), a network established by the National Institute of Allergy and Infectious Diseases (NIAID) to conduct clinical trials, observational studies and basic research to better understand and treat food allergy.
The research is part of an ongoing investigation of 512 children who were enrolled at 3 to 15 months old and were allergic to milk or egg. Investigators are carefully following these children to see whether their allergies resolve or if new allergies, particularly peanut allergy, develop. The study is ongoing at research hospitals in Baltimore; Denver; Durham, N.C.; Little Rock, Ark.; and New York City.
CoFAR investigators advised parents and caregivers to avoid giving their children foods that could cause an allergic reaction. Study participants also received an emergency action plan, describing the symptoms associated with allergic reactions to foods and what to do if a child has an allergic reaction, along with a prescription and instructions on how to give epinephrine if a severe reaction occurred.
"We have a lot of work to do, whether it's in education - working with parents, caregivers and health care providers to make sure we are providing appropriate information regarding allergen avoidance - or in treatment, to make sure caregivers know how to accurately assess food reactions and respond with appropriate therapy," said study co-author Tamara Perry, M.D., assistant professor in the UAMS College of Medicine, division of pediatric allergy/immunology at Arkansas Children's Hospital and an ACHRI researcher.
"Different types of educational settings may be necessary, such as hands-on, practical training sessions to augment written educational material," Perry said. "And we must make sure the education is being reinforced across all settings: schools, day cares, primary care providers and others."
Data compiled from patient questionnaires and clinic visits over three years showed that
72 percent of the children had a food-allergic reaction, and that 53 percent of the children had more than one reaction, with the majority of reactions being to milk, egg or peanut. This translated into a rate of nearly one food-allergic reaction per child per year.
Approximately 11 percent of the reactions were classified as severe and included symptoms such as swelling in the throat, difficulty breathing, a sudden drop in blood pressure, dizziness or fainting. Virtually all of the severe reactions were caused by ingestion of the allergen rather than inhalation or skin contact.
"This study shows, I think, that we're somehow not conveying the practical part of this - learning to deal with and manage food allergies on a day-to-day basis," Jones said. "We need to look for ways to bridge that gap and make sure we're doing all we can to protect children with food allergies from accidental ingestion."
In only 30 percent of the severe reactions did caregivers administer epinephrine, a life-saving drug that alleviates the symptoms of severe allergic reactions by increasing heart rate, constricting blood vessels and opening the airway. Investigators found that caregivers did not give children epinephrine for a number of reasons: the drug was not available, they were too afraid to administer it, they did not recognize the symptoms as those of an allergic reaction, or they did not recognize the reaction as severe.
Almost 90 percent of allergic reactions to egg, milk or peanut occurred after a child accidentally ate the food. The reasons for the accidental exposures included caregivers misreading food labels, not checking a food for an allergen, and unintentionally allowing a food allergen to come into contact with other foods (cross-contamination).
The study also found that about 11 percent of allergic reactions to egg, milk or peanut occurred after a caregiver -- most often a parent -- intentionally provided a child the allergenic food.
This was an unexpected finding because intentional exposures to allergenic food have typically been reported in teenagers, who tend to take more risks or who might be embarrassed about their food allergy, Perry said.
CoFAR investigators are exploring possible reasons for these intentional exposures, but they speculate that it could reflect parents' at-home tests to determine if children have outgrown the food allergy. Because giving children allergenic foods could possibly result in life-threatening reactions, such testing should only be conducted under the direct supervision of a health care professional trained in performing food challenges. The study findings reinforce the importance of caregivers working closely with their doctors to understand how to effectively manage a child's food allergy.
The study is to continue through 2015.