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Abstract Background Poor response rates in prevalence surveys can lead to nonresponse bias thereby compromising the validity of prevalence estimates. We conducted a telephone survey of randomly selected households to estimate the prevalence of food allergy in the 10 Canadian provinces between May 2008 and March 2009 (the SCAAALAR study: Surveying Canadians to Assess the Prevalence of Common Food Allergies and Attitudes towards Food LAbeling and Risk). A household response rate of only 34.6% was attained, and those of lower socioeconomic status, lower education and new Canadians were underrepresented. We are now attempting to target these vulnerable populations in the SPAACE study (Surveying the Prevalence of Food Allergy in All Canadian Environments) and are evaluating strategies to increase the response rate. Although the success of incentives to increase response rates has been demonstrated previously, no studies have specifically examined the use of unconditional incentives in these vulnerable populations in a telephone survey. The pilot study will compare response rates between vulnerable Canadian populations receiving and not receiving an incentive. Findings Randomly selected households were randomly assigned to receive either a $5 incentive or no incentive. The between group differences in response rates and 95% confidence intervals (CIs) were calculated. The response rates for the incentive and non-incentive groups were 36.1% and 28.7% respectively, yielding a between group difference of 7.4% (−0.7%, 15.6%). Conclusion Although the wide CI precludes definitive conclusions, our results suggest that unconditional incentives are effective in vulnerable populations for telephone surveys.

Abstract Background There has been no large study characterizing selection bias in allergy and evaluating school personnel’s ability to use an epinephrine auto-injector (EpiPen®). Our objective was to determine if the consent process introduces selection bias by comparing 2 methods of soliciting participation of school personnel in a study evaluating their ability to demonstrate the EpiPen®. Methods School personnel from randomly selected schools in Quebec were approached using a 1) partial or 2) full disclosure approach and were assessed on their ability to use the EpiPen® and identify anaphylaxis. Results 343 school personnel participated. In the full disclosure group, the participation rate was lower: 21.9% (95%CI, 19.0%-25.2%) versus 40.7% (95%CI, 36.1%-45.3%), but more participants achieved a perfect score: 26.3% (95%CI, 19.6%-33.9%) versus 15.8% (95%CI, 10.8%-21.8%), and identified 3 signs of anaphylaxis: 71.8% (95%CI, 64.0%-78.7%) versus 55.6% (95%CI, 48.2%-62.9%). Conclusions Selection bias is suspected as school personnel who were fully informed of the purpose of the assessment were less likely to participate; those who participated among the fully informed were more likely to earn perfect scores and identify anaphylaxis. As the process of consent can influence participation and bias outcomes, researchers and Ethics Boards need to consider conditions under which studies can proceed without full consent. Despite training, school personnel perform poorly when asked to demonstrate the EpiPen®.

Competing Interests: Disclosures Dr Chan has received research support from DBV Technologies; has been a member of advisory boards for Pfizer, Miravo, Medexus, Leo Pharma, Kaleo, DBV, AllerGenis, Sanofi Genzyme, Bausch Health, Avir Pharma, AstraZeneca, and ALK; and was co-lead of the Canadian Society of Allergy and Clinical Immunology oral immunotherapy guidelines. Dr Pratap-Singh holds the BC Ministry of Agriculture Endowed Professorship in Food and Beverage Innovation. Drs Williams, Guo and Soller have no conflicts to disclosure.

Background: Because of its favorable safety, sublingual immunotherapy (SLIT) for food allergy has been proposed as an alternative treatment for those in whom oral immunotherapy (OIT) is of higher risk-older children, adolescents, adults, and those with a history of severe reactions. Although safe, SLIT has been shown to be less effective than OIT., Objective: To describe the safety of multifood SLIT in pediatric patients aged 4 to 18 years and the effectiveness of bypassing OIT buildup with an initial phase of SLIT., Methods: Patients aged 4 to 18 years were offered (multi)food SLIT. Patients built up to 2 mg protein SLIT maintenance over the course of 3 to 5 visits under nurse supervision. After 1 to 2 years of daily SLIT maintenance, patients were offered a low-dose oral food challenge (OFC) (cumulative dose, 300 mg protein) with the goal of bypassing OIT buildup., Results: Between summer 2020 and winter 2023, 188 patients were enrolled in SLIT (median age, 11 years). Four patients (2.10%) received epinephrine during buildup and went to the emergency department, but none experienced grade 4 (severe) reaction. A subset of 20 patients had 50 low-dose OFCs to 300 mg protein and 35 (70%) OFCs were successful, thereby bypassing OIT buildup., Conclusions: In combination with very favorable safety of SLIT, with no life-threatening reactions and few reactions requiring epinephrine, we propose that an initial phase of SLIT to bypass supervised OIT buildup be considered for children in whom OIT is considered to be of higher risk., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Oral immunotherapy is an effective treatment for food allergies; however, its use in clinical practice is limited by resources and lack of standardized protocols for foods other than peanut. Previous studies have suggested that shrimp has a higher threshold for reaction than other allergenic foods, suggesting it may be safe to directly administer maintenance doses of immunotherapy., Methods: Children aged 3-17 years who had 1) skin prick test ≥3 mm and/or specific IgE level ≥0.35 kU/L and convincing objective IgE-mediated reaction to shrimp, or 2) no ingestion history and specific IgE level ≥5 kU/L, underwent a low-dose oral food challenge to 300 mg shrimp protein, with the goal of continuing daily ingestion of the 300 mg maintenance dose as oral immunotherapy., Results: Between January 2020 and April 2023, 17 children completed the low-dose oral food challenge. Nine (53%) tolerated this amount with no reaction, and 8 (47%) had a mild reaction (isolated oral pruritis or redness on chin). Sixteen (94%) continued maintenance low-dose oral immunotherapy eating 300 mg shrimp protein daily. None of the patients developed anaphylaxis related to the immunotherapy., Conclusion: Our case series suggests that some shrimp allergic patients being considered for oral immunotherapy should be offered a low-dose oral food challenge, to potentially bypass the build-up phase of immunotherapy., (© 2023 The Author(s).)

Background: Previous studies support the effectiveness of sesame oral immunotherapy (S-OIT) in patients >4 years old using maintenance doses of 1200 mg protein. However, tahini is often not palatable to children, and high-maintenance doses may not be possible for preschoolers., Objective: We studied the safety and effectiveness outcomes of preschoolers with sesame allergy who underwent low-dose S-OIT of 200 mg protein., Methods: Preschoolers with sesame allergy, with a history of objective reaction to sesame, and with either a positive skin prick test result (wheal diameter ≥3 mm) or sesame-specific IgE level ≥0.35 kU/L were included. Doses were escalated every 2 to 4 weeks until the maintenance dose of 200 mg of sesame protein was reached. The maintenance dose was continued daily for 1 year, followed by exit oral food challenge (OFC). Primary safety outcomes included allergic reactions grade 2 or higher and the need for epinephrine therapy during buildup. The primary effectiveness outcome was proportion of patients tolerating a minimum of 2000 mg sesame protein at exit OFC., Results: Twenty-eight preschoolers (median age, 33.5 months) were enrolled to receive S-OIT. During the buildup phase, 9 subjects (32.1%) had no reaction, and 8 (28.6%) and 11 (39.3%) had grade 1 and 2 reactions, respectively. One patient (3.57%) received epinephrine for a grade 2 reaction. Twenty-one (91.3%) of 23 eligible subjects underwent exit OFC; 18 (85.7%) of these 21 patients successfully completed exit OFC. One (4.8%) and 2 (9.5%) subjects had grade 1 and 2 reactions, respectively, during OFC., Conclusions: A lower and age-appropriate maintenance dose is safe and effective in desensitizing preschoolers with sesame allergy., (© 2023 The Author(s).)

Purpose: To assess knowledge of Canadian dietitians on the topics of food allergy and food allergy prevention guidelines, including introduction of allergenic solids to infants at risk of food allergy. Methods: An online survey was distributed via email listservs targeting Canadian dietitians. Results: In total, 144 of 261 dietitians completed the survey (60.5%). Respondents recommend introduction of peanut (89.5%) and allergenic solids (91.2%) within the recommended age of 4-6 months for infants at high risk of food allergy, but only 26.2% recommend offering peanut three times per week once it has been introduced. In identifying what constitutes an infant at high risk of developing peanut allergy, dietitians expressed lower comfort levels and lower number of correct responses. Conclusions: Dietitians demonstrated they are up to date regarding the timing of introduction of allergenic solids, but not the frequency of consumption once introduced, for infants at high risk of food allergy. They also expressed low comfort level identifying risk factors for peanut allergy. There are opportunities for further education of dietitians, as well as potential to further utilize dietitian services for the benefit of patients with food allergy or who are at risk for food allergy.

Allergists addressing gastrointestinal (GI) symptoms during oral immunotherapy (OIT) may be biased toward diagnoses related to OIT; however, non-OIT causes may occur. Although there is currently a lack of robust data for evidence-based treatment recommendations, we provide 3 real-world illustrative cases along with a proposed management algorithm for GI symptoms encountered during OIT. This algorithm was developed because of a significant clinical need, given the number of new-to-OIT providers that include practicing allergists, trainees transitioning into practice, and allied health care providers who manage GI symptoms in OIT patients. We developed the algorithm based on the opinions of community and academic allergy clinics across Canada with significant clinical experience offering infant, preschool, and school-aged OIT patients, with gastroenterologist input. Further research is needed to fill the knowledge gaps in the management of GI symptoms during OIT before formal recommendations can be suggested., (Copyright © 2022 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Background: Our group previously described preschool peanut oral immunotherapy (OIT) in a real-world, multicenter setting, suggesting that this therapy is safe for most preschoolers., Objective: To examine the safety and tolerability of tree nut (TN) OIT in preschoolers in the real world., Methods: As part of a Canada-wide quality improvement project, TN-OIT (cashew/pistachio, walnut/pecan, hazelnut, almond, and macadamia nut) was performed in preschoolers who had (1) a skin prick test wheal diameter greater than or equal to 3 mm or a specific IgE level greater than or equal to 0.35 kU/L and a convincing objective IgE-mediated reaction or (2) no ingestion history and a specific IgE level greater than or equal to 5 kU/L. Dose escalations were performed every 2 to 4 weeks till a maintenance dose of 300 mg of TN protein was reached. Symptoms were recorded and classified using the modified World Allergy Organization Subcutaneous Immunotherapy Reaction Grading System (1, mildest; 5, fatal)., Results: Of the 92 patients who started TN-OIT from 2018 to 2021, 79 (85.9%) underwent single-food TN-OIT and 13 (14.1%) underwent multifood TN-OIT to 2 (10.8%) or 3 (3.3%) TNs. Eighty-nine (96.7%) patients reached maintenance, and 4 (4.3%) dropped out. Sixty-five (70.7%) patients experienced reactions during buildup: 35 (38.0%) grade 1 reactions, 30 (32.6%) grade 2 reactions, no grade 3 or 4 reactions, and 2 (2.17%) received epinephrine., Conclusions: Preschool TN-OIT in a real-world, multicenter setting appears safe and tolerable, with results comparable with our previously reported peanut OIT findings., (Copyright © 2023 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Background: An understanding of how patient characteristics such as age, baseline peanut-specific IgE, and atopic comorbidities may influence potential safety outcomes during peanut oral immunotherapy (P-OIT) could aid in shared decision making between clinicians and patient families., Objective: This study explored the relationship between baseline patient characteristics and reactions during P-OIT using a large sample size to better understand potential risk factors influencing P-OIT safety., Methods: Data were obtained from the Food Allergy Immunotherapy (FAIT) registry, which collects real-world OIT data from community and academic allergy clinics across Canada. Multivariable logistic regression modeling was performed to examine the relationship between baseline patient characteristics and reactions during P-OIT. Multiple imputation was applied to reduce potential bias caused by missingness and to maximize the use of available information to preserve statistical power., Results: Between April 2017 and June 2021, a total of 653 eligible patients initiated P-OIT. Multivariable regression analysis showed pre-OIT grade 2+ initial reaction (odds ratio [OR] = 1.33, 95% confidence interval [CI] 1.10, 1.61), allergic rhinitis (OR = 1.60, 95% CI 1.08, 2.38), older age (OR = 1.01, 95% CI 1.00, 1.02), and higher baseline peanut-specific IgE (OR = 1.02, 95% CI 1.02, 1.03) were associated with grade 2+ reaction during P-OIT after adjusting for potential risk factors., Conclusion: Our study identified several clinically important risk factors for grade 2+ reactions during P-OIT: pre-OIT grade 2+ initial reaction, allergic rhinitis, older age, and higher baseline peanut-specific IgE. These results highlight the need for individualized risk stratification for OIT., (© 2023 The Authors.)

Background: The safety of pediatric food oral immunotherapy (Ped-OIT) has been depicted by some as less favorable than subcutaneous immunotherapy (SCIT) owing to the increased number of serious adverse events requiring epinephrine. A review of real-world data comparing Ped-OIT and SCIT safety is necessary to guide shared decision making., Objectives: Our aim was to compare the safety and adverse event profiles of peanut Ped-OIT and SCIT using Canadian real-word literature., Methods: We performed a retrospective review of recent Canadian real-world literature on peanut Ped-OIT and SCIT safety and adverse events., Results: The incidences of systemic reactions requiring epinephrine were 11 in 270 patients (4.07%) and 12 in 41,020 doses (0.029%) in a multicenter study in British Columbia, Alberta, Manitoba, and Nova Scotia studying 270 preschool-age children treated with peanut OIT. Similarly, a multicenter study in South-Western Ontario examining 160 patients between the ages of 1 and 17 years who were treated with peanut OIT showed that the incidences of systemic reactions requiring epinephrine were 5 in 160 patients (3.1%) and 8 in 52,751 doses (0.015%). A single-center retrospective review of 380 patients receiving aeroallergen SCIT showed that the incidences of systemic reactions requiring epinephrine were 28 in 380 patients (7.4%) and 1 in 1047 injection visits (0.095%). These findings are comparable to those of a review of 860 patients in Ontario who received either aeroallergen or venom SCIT, in which the incidence of systemic reaction requiring epinephrine was 10 in 4242 injections (0.24%)., Conclusion: Despite differences in the OIT protocols used and age groups studied, recent real-world data suggest that the safety of preschool peanut OIT or peanut OIT using a slower buildup schedule is comparable to that of SCIT., (© 2023 The Authors.)

Background: Oral food challenges (OFC) confer the highest sensitivity and specificity in diagnosis; however, uptake has been variable across clinical settings. Numerous barriers were identified in literature from inadequate training to resource access. OFC utilization patterns using billing data have not been previously studied., Objective: The objective of this study is to explore the geographic differences in utilization of OFCs across Ontario and Québec using anonymized billing data from 2013 to 2017., Methods: Anonymized OFC billing data were obtained between 2013 and 2017 from Ontario Health Insurance Plan (OHIP) and Régie de l'Assurance Maladie du Québec (RAMQ). The number of OFCs was extracted by location, billings, and physician demographics for clinic and hospital-based challenges., Results: Over the period studied, the number of OFCs increased by 92% and 85% in Ontario clinics and Québec hospitals, respectively. For Ontario hospitals, the number of OFCs increased by 194%. While Québec performed exclusively hospital-based OFCs, after controlling for the population, the number of OFCs per 100,000 residents annually were similar to Ontario at 50 and 49 OFCs, respectively. The number of OFCs varied across the regions studied with an annual rate reaching up to 156 OFCs per 100,000 residents in urban regions and as low as 0.1 in regions furthest from city centers., Conclusion: OFC utilization has steadily increased over the last decade. There has been marked geographical discrepancies in OFC utilization which could be driven by the location of allergists and heterogeneity in their practices. More research is needed to identify barriers and propose solutions to them., (© 2023. The Author(s).)

Introduction: Histologic diagnosis of eosinophilic esophagitis (EoE) involves peak eosinophil counts (PEC) being greater than 15 per high power field. The EoE Histology Scoring System (EoEHSS) was developed to comprehensively evaluate biopsies to better predict symptom and endoscopy response; we aimed to validate the EoEHSS in our provincial registry, where EoEHSS had not been employed., Methods: We reviewed 186 esophageal biopsies from 16 patients at diagnosis and follow-up. Statistical analyses were conducted to quantify how grade scores correlate with active EoE status and PEC counts, and each feature's ability to predict active disease., Results: Nearly all EoEHSS variables were associated with active EoE and high PEC, with basal zone hyperplasia, eosinophil abscesses, and surface epithelial alteration being most predictive in identifying active EoE., Conclusions: We validated and demonstrated each EoEHSS variable's strength in tracking traditional PEC counts, resulting in its adoption as a standard reporting element for our research registry.

Background: Parents commonly experience anxiety owing to their children's food allergies (FAs). Although FA-specific anxiety screening tools for adult and pediatric patients exist, a tool for parents with children with food allergy is lacking., Objective: To develop and validate a tool that measures parental anxiety related to their child's FA., Methods: To construct the instrument, items were developed based on consultations with stakeholders and review of existing literature. The instrument was then pilot tested, and items were modified based on relevance, importance, item-total correlations, and fit with the instrument's overall factor structure. The modified instrument was validated through assessing internal validity (reliability), convergent and discriminant validity, concurrent validity, and practical usefulness at 2 time points (precoronavirus disease 2019 and current)., Results: The scale showed excellent reliability (Cronbach's α = 0.95). It had a 4-factor structure that was replicated at the 2 time points. The 4 subscales were moderately correlated (between r = 0.438 and 0.744). The scale showed excellent convergent and discriminatory validity, correlating moderately with State Trait Anxiety Inventory and Generalized Anxiety Disorder, and highly with Food Allergy Quality of Life-Parental Burden. It also showed excellent concurrent validity, differentiating among many external variables. Most importantly, it successfully differentiated parents in need of psychological support for problems related to their child's FA., Conclusion: The Impairment Measure for Parental Food Allergy-associated Anxiety and Coping Tool fills a gap in the existing literature as a validated screening tool for parental anxiety associated with a child's FA, employing a multi-factor structure addressing multiple dimensions of anxiety and its functional impacts. It has excellent internal and external validity and is well-suited for use in both research and clinical settings to quickly determine which parents of children with FA are in need of further psychological support., (Copyright © 2022 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Recent guideline recommendations have shifted from recommending prolonged avoidance of allergenic foods in the first 3 years of life to a primary prevention approach involving the deliberate early introduction to infants at risk of developing food allergy. Despite this, some infants, especially those with severe eczema who are at highest risk for developing peanut allergy, fail to receive the preventative benefits of early peanut introduction due to hesitancy and other factors. Difficulty adhering to regular ingestion after introduction further reduces the effectiveness of primary prevention. As emerging real-world evidence has demonstrated that performing peanut oral immunotherapy (OIT) among infants is effective and safe, peanut OIT could be a treatment option for infants with peanut allergy. This review discusses the benefits, risks, and barriers to offering peanut OIT to infants who fail primary prevention strategies. We propose the novel concept that infants with peanut allergy be offered peanut OIT as soon as possible after failed peanut introduction through a shared decision-making process with the family, where there is a preference for active management rather than avoidance., (Copyright © 2022 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Background: Parenting a child with food allergy (FA) can lead to impaired quality of life and family functioning. Anxiety is a critical component of FA-associated distress and a potential target for therapeutic intervention. This systematic review aimed to clarify the concept of FA-specific anxiety (FAA) and its antecedents, consequences, and correlates and to determine the extent to which existing FA-specific outcome measures capture symptoms of parental distress and FAA., Methods: MEDLINE, EMBASE, PsycINFO, and CENTRAL were searched for qualitative and quantitative studies examining distress or anxiety in parents of children with FA through August 2020. This review was registered with PROSPERO (CRD42020208316) and conducted in accordance with PRISMA guidelines., Results: Ninety-eight studies were included in the final narrative synthesis. Most participants were mothers, and reporting of demographic data was limited. Parents identified anxiety as the most burdensome form of FA-specific emotional distress. Several allergy-related factors as well as medical and psychosocial interventions were associated with reduced parental anxiety and distress. However, affective, cognitive, and behavioral dimensions of FAA were only partially addressed by existing measures for general anxiety symptoms and FA-specific parental factors., Conclusions: FAA contributes to distress and functional impairment among parents of children with FA. Current FA-specific parent measures fail to adequately capture dimensions of FAA, suggesting that further work is needed to improve the assessment and monitoring of FAA and its impacts. Characterization of this construct represents an initial step in developing standardized methods for assessing and monitoring FAA in clinical populations., (© 2021 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.)