Rate of Multiple Food Allergies Is High in US Pediatric and Adult Populations

Children and adults who report having 1 or more current food allergies (FAs) have a high rate of multiple FAs, and 4 major phenotypes of multi-FA were identified in both populations, according to study findings published in the Annals of Allergy, Asthma & Immunology.

Researchers sought to determine the prevalence, characteristics, determinants, psychosocial burden, and distribution of multi-FA among US children and adults.

A national, cross-sectional FA questionnaire was administered electronically and by telephone from October 1, 2015, through September 31, 2016, to English- and/or Spanish-speaking adults residing in a US household. The primary outcomes were the estimated prevalence of immunoglobulin E (IgE)-mediated current allergy to multiple foods among children and adults.

Reported FAs were regarded as “convincingly IgE-mediated” if the most severe reaction to that food included at least 1 symptom on the symptom list created for the study, even if the allergies were reported to be physician-diagnosed. Convincing FAs for which a physician’s diagnosis was reported were classified as “physician confirmed.”

The surveys were completed for 38,408 children (mean age, 8.7 years; 95% CI, 8.5-8.8) and by 40,443 adults (mean age, 46.8 years; 95% CI, 46.3-47.2).

Of the 11.4% (95% CI, 10.8%-12.0%) of children who were reported as having at least 1 current FAs regardless of clinical history, 45% reported having multiple current FAs. Of the 7.6% (95% CI, 7.1%-8.1%) of children who were reported to have at least 1 current FA that met previously published criteria for convincingly IgE-mediated FA, 40% reported multiple current convincingly IgE-mediated FAs. In addition, of the 4.7% (95% CI, 4.3%-5.0%) of children reported to have at least 1 physician-diagnosed current FA that met symptom-report criteria for convincingly IgE-mediated FA, 38% reported multiple physician-confirmed FAs.

Among adults, of the 19.0% (95% CI, 18.5%-19.5%) who reported at least 1 current FA regardless of clinical history, 48% reported multiple FAs. Of the 10.8% (95% CI, 10.4%-11.1%) of adults who reported at least 1 current FA that met established symptom-report criteria for convincingly IgE-mediated FA, 46% reported multiple current convincingly IgE-mediated FAs. Of the 5.1% (95% CI, 4.9%-5.4%) of adults who reported at least 1 physician-diagnosed current FA that met established symptom-report criteria for convincingly IgE-mediated FA, 42% reported multiple physician-confirmed FAs.

In children, the prevalence of multiple vs single instances of convincing FA was not significantly different across age strata, as about 33% of children younger than 3 years of age with convincing FAs were reported to have multiple FAs vs about 40% of those 3 years of age or older. For adults, the prevalence of multiple vs single instances of convincing FA was significantly different across age strata, as about 48% of adults aged 18 to 49 years with convincing FAs reported multiple FAs compared with 37.5% of those aged 70 years or older.

The lifetime reported prevalence of physician-diagnosed atopic comorbidities increased significantly as the number of reported current convincing FAs increased for the pediatric and adult groups with convincing FAs (P <.001 for all).

Emergency department (ED) visits related to FAs within the previous 12 months and during an individual’s lifetime were associated with the number of current convincing FAs (P <.001 for both), and a higher number of FAs was associated with greater odds of an ED visit. An increased number of reported convincing FAs was also associated with greater perceived FA severity and related psychosocial burden.

Additional analysis revealed 4 major multi-FA phenotypic clusters, including milk/egg dominant, seafood dominant, peanut/tree nut dominant, and broadly multi-food-allergic.

In discussing study limitations, the researchers noted that the reported estimates likely included patients whose nonfood allergies had resolved by the time of survey assessment and patients who were misdiagnosed. Another limitation was the inability to clinically confirm reported allergy cases, which likely led to overestimation of the prevalence of IgE-mediated allergies, including those to food, drugs, latex, insect stings, and venom.

“The US population-level burden of multi-FA is high among both children and adults

and data indicate the presence of four major phenotypes of multi-FA in both populations,” study authors concluded. “[U]nderstanding the phenotypes of multi-FA can help inform future research and targeted therapies as well as strategies to minimize the physical and psychosocial burden of this disease,” the investigators added.

Disclosure: One of the study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.