55 - Low Fill Rates for Epinephrine Auto-Injectors in Pediatric Patients Covered by Medicaid Following Presentation for Anaphylaxis

Publication Number: 3052.55

Peyton Bennett, Monroe Carell Jr. Children's Hospital at Vanderbilt, Nashville, TN, United States; Donald H. Arnold, Monroe Carell Jr. Children's Hospital at Vanderbilt, Nashville, TN, United States; Tim Dribin, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States; Matthew S. Krantz, Vanderbilt University Medical Center, Nashville, TN, United States; Barron Frazier, Monroe Carell Jr. Children's Hospital at Vanderbilt, Nashville, TN, United States

Background: Anaphylaxis is a potentially life-threatening allergic reaction requiring immediate intervention. Epinephrine is the initial pharmacotherapy and is available commercially as an autoinjector. Despite current guidelines recommending epinephrine auto-injector (EAI) prescription and education on use at discharge, adherence to filling these prescriptions remains uncertain in pediatric populations. The highest risk of biphasic anaphylaxis, a recurrent severe reaction after resolution of symptoms, is in the first 72 hours following the initial event. Obtaining an EAI promptly following discharge is necessary for treatment of both biphasic anaphylaxis and future anaphylaxis events.

Objective: We sought to evaluate EAI fill rates in pediatric patients covered by Tennessee Medicaid (TennCare) following outpatient visits, emergency department (ED) visits, and hospitalizations for anaphylaxis and identify factors associated with fill rates.

Design/Methods: We performed a retrospective cohort study from July 2021 to June 2023. Sociodemographic and claims data were collected from the TennCare database. Those included in the study were children with sustained TennCare enrollment, 2-17 years of age, who presented to care for anaphylaxis as defined by ICD10 codes associated with the visit. Descriptive analyses were used to summarize patient demographic data including age, sex, geographic factors, and the CDC Social Vulnerability Index (SVI). Univariate analyses and a multivariate logistic regression were used to evaluate factors associated with failure to fill an EAI prescription.

Results: Of 2,066 children covered by TennCare who were evaluated for anaphylaxis during the study period, 1,878 met inclusion criteria. The median patient age was 9 [IQR 5-13], and 52.6% were male. The EAI prescription fill rate was 23.6% (n=443), with only 16.4% (n=307) filled during the highest risk period for biphasic anaphylaxis. In the multivariable model, patients age 11-13 years (aOR 0.60 [0.40, 0.89]), 14-17 years (aOR 0.64 [0.42, 0.48]) and with a high SVI (aOR 0.67 [0.46, 0.98]) were least likely to fill the prescription

Conclusion(s): Overall, EAI fill rates were strikingly low across all variables, with fewer than 25% of children filling following presentation for anaphylaxis, representing a significant public health concern. Age, visit type, and SVI scores were associated with failure to fill an EAI after adjusting for relevant covariates, highlighting opportunities for improved access to care and tailored interventions.