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Prevalence of Anaphylaxis Increasing in U.S. Infants and Toddlers

Key findings

  • This analysis of a large U.S. administrative database aimed to discern trends in pediatric emergency department (ED) visits for anaphylaxis, food-induced anaphylaxis (FIA) and overall acute allergic reactions (AAR)
  • Among infants and toddlers (age <3 years old), the number and proportion of ED visits for anaphylaxis more than doubled between 2006 and 2015 (P for trend <0.001 for both measures)
  • In all age groups of children (3 to <6 years, 6 to <12 and 12 to 17), the number of ED visits for FIA, anaphylaxis, food-induced AAR and overall AAR increased significantly
  • The percentage of infants and toddlers who presented to an ED for anaphylaxis and then were admitted to the hospital decreased significantly, from 19% in 2006 to 6% in 2015 (P for trend <0.001)
  • Among infants and toddlers presenting with anaphylaxis, the rate of epinephrine administration in the ED increased more than fourfold, from 5% in 2006 to 24% in 2015 (P for trend <0.001)

Rates of anaphylaxis appear to be rising among U.S. children, but infants and toddlers have not been well studied. That's worrisome because in this population there are high rates of food-induced anaphylaxis without a preceding diagnosis—so few families own an epinephrine autoinjector at the time of the initial reaction.

Lacey B. Robinson, MD, MPH, allergist in the Division of Rheumatology, Allergy and Immunology, and Carlos A. Camargo, Jr., MD, DrPH, Conn Chair in Emergency Medicine in the Department of Emergency Medicine at Massachusetts General Hospital, and colleagues used a large, nationally representative, all-payer database to study trends in the emergency department (ED) visits among infants and toddlers with anaphylaxis between 2006 and 2015.

In The Journal of Allergy and Clinical Immunology: In Practice, they report the number and proportion of ED visits for anaphylaxis more than doubled while rates of hospitalization declined.

Study Methods

The study made use of the Nationwide Emergency Department Sample, maintained by the federal government, which contains data on >143 million ED discharges per year. The team measured the following overlapping measures for infants and toddlers (age <3 years old) and older children (ages 3 to <6, 6 to <12 and 12 to 17 years old) from 2006–2015:

  • Acute allergy reaction (AAR, the broadest category)—including anaphylaxis, allergy unspecified or dermatitis due to ingested food
  • Anaphylaxis to food or non-food triggers
  • Food-induced acute allergic reaction (FAAR)—including food-induced anaphylaxis, dermatitis due to ingested food
  • Food-induced anaphylaxis (FIA)

Number of ED Visits

Among infants and toddlers:

  • The number of ED visits for anaphylaxis increased from 15 per 100,000 U.S. population in 2006 to 32 per 100,000 in 2015 (P for trend <0.001)
  • The proportion of ED visits for anaphylaxis increased from 20 per 100,000 visits to 50 per 100,000 visits (P for trend <0.001)

In all age groups of children, the number of ED visits for FIA, anaphylaxis, FAAR and AAR increased significantly.

ED Visit Disposition

The proportion of infants and toddlers who presented to an ED for anaphylaxis and were then admitted to the hospital decreased significantly, from 19% in 2006 to 6% in 2015 (P for trend <0.001).

Predictors of Hospitalization

Factors predicting greater odds of hospitalization of infants and toddlers included male sex, private insurance, highest two quartiles of median household income and presentation to an urban hospital or metropolitan teaching hospital.

Epinephrine Administration in the ED

Among infants and toddlers presenting with anaphylaxis, the rate of epinephrine administration in the ED increased markedly, from 5% in 2006 to 24% in 2015 (P for trend <0.001).

An Emerging Risk

This study was conducted before the publication of the LEAP trial in 2015 and the NIH Addendum Guidelines to Prevent Peanut Allergy in 2017, which recommend the introduction of peanut-containing food into infant diets as early as age four to six months.

This study shows that even prior to that paradigm shift, anaphylaxis was an emerging risk for infants and toddlers, and the increasing prevalence of food allergy was likely a key driving force behind the rise in ED visits for anaphylaxis. Another factor to consider is increased diagnosis due to rising awareness of anaphylaxis and food allergy among children.

The decline in hospitalizations might be due to improved management of anaphylaxis (especially early use of epinephrine), low severity of presentation and changes in health care utilization, such as greater availability of ED observation units.

15
per 100,000 population — number of ED visits for anaphylaxis by U.S. infants and toddlers in 2006

32%
per 100,000 population — number of ED visits for anaphylaxis by U.S. infants and toddlers in 2015

19%
of U.S. infants and toddlers with anaphylaxis were admitted to a hospital from an ED in 2006

6%
of U.S. infants and toddlers with anaphylaxis were admitted to a hospital from an ED in 2015

Learn more about the Allergy Unit at Mass General

Refer a patient to the Division of Rheumatology, Allergy and Immunology

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