Epidemiology of anaphylaxis: findings of the American College of Allergy, Asthma and Immunology Epidemiology of Anaphylaxis Working Group.

ObjectiveTo improve understanding of the epidemiology of anaphylaxis.Data sourcesWe performed a qualitative review by hand of the major epidemiology studies of anaphylaxis. This review was restricted to articles in the English language.Study selectionArticles chosen were selected by the committee and dated back to 1968. There was no specific criterion used for selection except the determination of the members of the committee.ResultsData on anaphylaxis incidence and prevalence are sparse and often imprecise. Findings are based on diverse study designs and are not entirely comparable. These factors have contributed to widely varying estimates of the frequency of this important condition. The roundtable discussion led to an improved estimation of the frequency of anaphylaxis: approximately 50 to 2,000 episodes per 100,000 persons or a lifetime prevalence of 0.05% to 2.0%. The largest number of incident cases is among children and adolescents. In addition to underdiagnosis, we noted undertreatment, especially for those at highest risk (ie, those without immediate access to treatment with epinephrine).ConclusionsAnaphylaxis is a relatively common problem, affecting up to 2% of the population. Further data on epinephrine dispensing could improve current estimates. Another way to improve current understanding would be through better population-based study designs in different geographic regions. A recurring theme was the importance of broader access to self-injectable epinephrine for high-risk populations. An improved epidemiologic understanding of this disorder would aid ongoing efforts to reduce morbidity and mortality from anaphylaxis and could provide important clues for primary prevention.