Increasing anaphylaxis hospitalizations in the first 2 decades of life: New York State, 1990 -2006.

Background: Although an increase in the occurrence of anaphylaxis has been reported in several parts of the world, this phenomenon has not been described in the United States.

Objective: To characterize anaphylaxis hospitalizations in New York State in patients younger than 20 years.

Methods: Using a statewide administrative database, hospital admissions of patients with an allergic disease (anaphylaxis, angioedema, urticaria, and allergy unspecified) as the primary diagnosis were analyzed from 1990 through 2006 in New York State. Admission rates were calculated for the allergic disease groups, as were hospitalization characteristics. Statistical modeling and group comparisons were performed with the use of negative binomial distribution analysis.

Results: For patients younger than 20 years, the anaphylaxis hospitalization rate increased by more than 4-fold during the study period and by 2002 exceeded the combined hospitalization rates for urticaria, angioedema, and unspecified allergy. After the widespread adoption of food anaphylaxis codes in 1994, food anaphylaxis predominated hospitalizations for anaphylaxis. Peanut was the most common food allergen in food anaphylaxis admissions. The anaphylaxis hospitalization rate for males was significantly greater than that of females (risk ratio, 1.45; 95% confidence interval, 1.26-1.66). Blacks were not disproportionately hospitalized for anaphylaxis. An overall bimodal age distribution showed peaks in the very young and in teens.

Conclusion: These data demonstrate that in a populous Northeastern state in the United States, anaphylaxis requiring hospitalization is increasing in the age group younger than 20 years.