Barriers and Enablers of Dietary Reintroduction Following Negative Oral Food Challenge: A Scoping Review

Background: After a negative oral food challenge (OFC), it is recommended for the individual to continue to consume the historical allergen regularly. However, the proportions of families achieving sustained reintroduction, and enablers and barriers for reintroduction, are currently unclear. Objective: To understand the frequency and definitions of optimal food reintroduction in children and adolescents after a negative OFC, and associated barriers and enablers. Method: We conducted a scoping review guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews of four databases (PubMed, Embase, CINAHL, and Web of Science) from 2000 until the present. Medical Subject Headings guided our systematic search, and dual screening and extraction were performed. We applied descriptive analysis to examine key themes aligned with our research questions. Results: In total, 2,270 articles were screened and 22 studies were included across nine countries. Peanuts were the most studied food (17 studies; 749 OFCs), followed by cow's milk (12 studies; 625 OFCs), hazelnut (four studies; 361 OFCs) and hen's egg (11 studies; 340 OFCs). What was considered to be a successful reintroduction was poorly and inconsistently described. Successful reintroduction (as defined by the authors) ranged from 14% to 86%, with failed reintroduction up to 50%. Nineteen studies (86%) examined barriers or enablers of reintroduction. Primary barriers were fear and anxiety as well as symptoms with reintroduction and aversion to or refusal of the food, whereas younger age, male sex, and guidance from clinicians were commonly reported enablers. Conclusion: The number of families who do not reintroduce foods after OFC remains high, and clinicians need high-quality data to support families better.