Temporal Trends in Epinephrine Dispensing and Allergy/Immunology Follow-up Among Emergency Department Anaphylaxis Patients in the United States, 2005-2014

Background: Anaphylaxis is a potentially life-threatening allergic reaction; measures including prescription of an epinephrine autoinjector (EAI) and allergy/immunology (A/I) follow-up may prevent future morbidity. Objective: The objective of this study was to evaluate trends in outpatient management of anaphylaxis by studying EAI dispensing and A/I follow-up among patients seen in the emergency department (ED) for anaphylaxis from 2005 through 2014. Methods: We analyzed administrative claims data from the OptumLabs Data Warehouse database using an expanded International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code algorithm. Results: The study cohort comprised 18,279 patients with a mean age of 39 years; 58% were female, and 86% were discharged from an ED. Within 1 year after discharge, 46% had filled an EAI prescription and 29% had A/I follow-up. Overall, from 2005 to 2014, annual rates of filled EAI prescriptions and A/I follow-up did not change. Among children (aged <18 years), rates increased for filled EAI prescriptions (16.1% increase; P = .02 for trend) and A/I follow-up (18.8% increase; P = .048 for trend). Rates decreased for A/I follow-up among adults (15.4% decrease; P = .002 for trend). Overall rates of filled EAI prescriptions were highest in those with venom-induced (73.9 per 100 ED visits) and food-induced anaphylaxis (69.4 per 100 ED visits); the lowest rates were among those with medication-related anaphylaxis (18.2 per 100 ED visits). Conclusions: Over the past decade, rates of EAI dispensing and A/I follow-up after an ED visit for anaphylaxis have remained low, suggesting that patients may not be prepared to manage future episodes.