Research indicates that around 12 percent of all children with diagnosed peanut allergies are accidentally exposed to peanuts in any given year, and that the majority of those exposures take place inside their own homes.
Research indicates that around 12% of all children with diagnosed peanut allergies are accidentally exposed to peanuts in any given year, and that the majority of those exposures take place inside their own homes.
Previous estimates of accidental exposure, which rested on far less data, varied widely. Some asserted that just 3% of all children with diagnosed food allergies suffered a reaction such as anaphylaxis in any given year. Others put the number as high as 50%.
The new figure stems from a study that recruited 1,941 children from allergy clinics in Canada and followed them for up to 10 years. Parents filled out questionnaires when their children entered the study and continue to fill out follow-up questionnaires, which originally came every 2 years and now come every year.
Researchers found that 429 children experienced 567 accidental exposures over the course of 4,589 patient-years. That translates to an annual incidence rate of 12.4% (95% confidence interval [CI], 11.4% to 13.4%).
Lower risk of accidental exposure was significantly associated with longer disease duration (adjusted hazard ratio [HR], 0.90; 95% CI, 0.88 to 0.93) and having other food allergies (HR, 0.81; 95% CI, 0.68 to 0.96) Higher risk of accidental exposure was associated with being 13 years or older at the time of study entry (HR, 2.22; 95% CI, 1.44 to 3.41) and residing in a single parent household (HR, 1.55; 95% CI, 1.14 to 2.10).
Roughly 37% of all accidental exposures occurred at home, while 14.3% occurred at the homes of friends or relatives, 9.3% occurred in restaurants, 4.9% occurred at schools or day-care centers that prohibited peanuts, 3.0% occurred at schools or day-care centers that allowed peanuts, and 31.6% occurred at other places or unknown places.
The study authors suggested several possible explanations for the fact that children were not significantly less likely to be exposed to peanuts at facilities that prohibited peanuts than they were at facilities that allowed them.
“Failure to observe such a decreased rate in facilities restricting peanut may be due to increased awareness and enhanced vigilance among parents, school personnel, and children in schools permitting peanut,” they wrote in Clinical and Translational Allergy.
“Further, peanut-free policies may create a false sense of security and foods brought to such facilities may inadvertently contain peanut and children who are allergic may believe that it is safe to share foods as they believe they are guaranteed to be peanut free.”
Patients in the cohort were, on average, 6.9 years old when their parents filled out the initial questionnaire (standard deviation, 4.0 years) and had been diagnosed with peanut allergies for 4.7 years (standard deviation, 4.0 years). The average length of follow-up with each patient was 2.4 years (standard deviation, 1.4 years).
In those cases when children in the study were exposed to peanuts, neither caregivers nor medical professionals (in those cases when children saw medical professionals) often failed to respond properly.
No treatment was administered after 36.5% of the 148 accidental exposures that produced mild reactions, 25.6% of the 292 that produced moderate reactions, and 14.1% of the 85 that produced severe reactions. (The reaction severity was unknown for 42 of the accidental exposures and treatment was unknown for 37 of those reactions.)
Medical attention was sought after only 73 (25.0%) of the 292 moderate reactions and 36 (42.4%) of the 85 severe reactions. Physicians administered epinephrine in response to only 22 (30.1%) of the 73 moderate cases they treated and half of the 36 severe cases they treated.
“Despite increased awareness, accidental exposures continue to occur, mainly at home, and most are managed inappropriately by both health care professionals and caregivers,” the study authors wrote. “Consequently, more education is required on the importance of strict allergen avoidance and the need for prompt and correct management of anaphylaxis.”