Design of the Intervention to Reduce Early Peanut Allergy in Children (iREACH): A practice-based clinical trial

BACKGROUND

Introducing peanut products early can prevent peanut allergy (PA). The "Addendum guidelines for the prevention of PA in the United States" (PPA guidelines) recommend early introduction of peanut products to low and moderate risk infants and evaluation prior to starting peanut products for infants at high risk for PA (those with severe eczema and/or egg allergy). Rapid adoption of guidelines could aid in lowering the prevalence of PA. The Intervention to Reduce Early (Peanut) Allergy in Children (iREACH) trial was designed to promote PPA guideline adherence by pediatric clinicians.

METHODS

A two-arm, cluster-randomized, controlled clinical trial was designed to measure the effectiveness of an intervention that included clinician education and accompanying clinical decision support tools integrated in electronic health records (EHR) versus standard care. Randomization was at the practice level (n = 30). Primary aims evaluated over an 18-month trial period assess adherence to the PPA guidelines using EHR documentation at 4- and 6-month well-child care visits aided by natural language processing. A secondary aim will evaluate the effectiveness in decreasing the incidence of PA by age 2.5 years using EHR documentation and caregiver surveys. The unit of observation for evaluations are individual children with clustering at the practice level.

CONCLUSION

Application of this intervention has the potential to inform the development of strategies to speed implementation of PPA guidelines.

Rates of New Peanut Allergy and Discontinuation Following Introduction in High-Risk Infants

BACKGROUND

Peanut introduction guidelines recommend that infants with severe eczema and/or egg allergy consume 6 g of peanut protein weekly to prevent peanut allergy. Rates of new peanut allergy after introduction and adherence remain under study.

OBJECTIVE

To determine compliance with peanut introduction guidelines, rates of new peanut allergy, and reasons for discontinuation of peanut consumption in a cohort of high-risk infants.

METHODS

A prospective cohort of 4- to 11-month-old high-risk infants (defined as moderate-severe eczema or non-peanut food allergy or a first-degree relative with peanut allergy) with no prior peanut exposure who were determined to not be peanut allergic were recommended to introduce 6 g of peanut protein weekly. Participants were followed to 30 months with 2 in-person visits and monthly questionnaires.

RESULTS

Two hundred seventy-seven infants were followed. At last follow-up, 245 (88%) were consuming some peanut protein with median weekly consumption of 3 g (interquartile range: 1-5 g). New peanut allergy developed in 6 (2%), with 2 of those cases consistent with food protein-induced enterocolitis syndrome. Fear of reaction in another household member was the most common reason for peanut discontinuation. Reactions to peanut after introduction in the index infant occurred in <2% of peanut-allergic siblings and in 20% of peanut-allergic parents.

CONCLUSION

We found low rates of new peanut allergy and generally low rates of peanut discontinuation after introduction in our high-risk cohort. However, families of high-risk infants require significant support with introduction, especially those with another peanut-allergic member.

Risk subgroups and intervention effects among infants at high risk for peanut allergy: A model for clinical decision making

BACKGROUND

The Learning Early About Peanut Allergy (LEAP) trial showed that early dietary introduction of peanut reduced the risk of developing peanut allergy by age 60 months in infants at high risk for peanut allergy. In this secondary analysis of LEAP data, we aimed to determine risk subgroups within these infants and estimate their respective intervention effects of early peanut introduction.

METHODS

LEAP raw data were retrieved from ITNTrialShare.org. Conditional random forest was applied to participants in the peanut avoidance arm to select statistically important features for the classification and regression tree (CART) analysis to group infants based on their risk of peanut allergy at 60 months of age. Intervention effects were estimated for each derived risk subgroup using data from both arms. Our main model was generated based on baseline data when the participants were 4-11 months old. Specific IgE measurements were truncated to account for the limit of detection commonly used by laboratories in clinical practice.

RESULTS

The model found infants with higher predicted probability of peanut allergy at 60 months of age had a similar relative risk reduction, but a greater absolute risk reduction in peanut allergy with early introduction of peanut, than those with lower probability. The intervention effects were significant across all risk subgroups. Participants with baseline peanut sIgE ≥0.22 kU/L (n = 78) had an absolute risk reduction of 40.4% (95% CI 27.3, 51.9) whereas participants with baseline peanut sIgE<0.22 kU/L and baseline Ara h 2 sIgE <0.10 kU/L (n = 226) had an absolute risk reduction of 6.5% (95% CI 2.6, 11.0). These findings were consistent in sensitivity analyses using alternative models.

CONCLUSION

In this study, risk subgroups were determined among infants from the LEAP trial based on the probability of developing peanut allergy and the intervention effects of early peanut introduction were estimated. This may be relevant for further risk assessment and personalized clinical decision-making.

Food allergies: Updates for nurses

ABSTRACT

Food allergies are on the rise; the incidence and types of foods implicated have increased worldwide. While peanut allergies are the most well-known, allergies exist to almost all types of foods. This article discusses various types of food allergies along with the most recent prevention and treatment strategies.

Reaching Communities Through Food Allergy Advocacy, Research, and Education: A Comprehensive Analysis

This article explores the multifaceted approach of food allergy (FA) advocacy, research, and education to address the diverse challenges associated with FA, such as disparities in socioeconomic status, food security, quality of life, and the overall burden of the disease. Advocacy initiatives are instrumental in driving policy changes, raising public awareness, and directing substantial research funding, with a focus on reducing disparities. They have influenced allergen labeling regulations and improved access to epinephrine, emphasizing the importance of school-based management plans, especially in underserved communities. Research in FA informs medical practices and offers them hope for improved treatments. Recent breakthroughs in peanut allergy prevention and oral immunotherapy trials exemplify the potential for advancements while highlighting the need to address disparities in health care access. Education is a critical tool for prevention, raising awareness, and reducing the risk of allergic reactions. Efforts should be tailored to reach marginalized communities, particularly in schools where education on FA management is essential. Collaborating directly with communities is imperative to ensure inclusivity and address disparities. Barriers such as mistrust, language and cultural differences, and lack of diversity among researchers must be overcome to encourage diverse participation in research studies. This article concludes by emphasizing the significance of a comprehensive approach to FA research that prioritizes equity and inclusivity. The call to action highlights the need for global initiatives to reshape the landscape of FA care and address disparities in health care access and outcomes.

Development of peanut, sesame and tree nut allergy in Polish children at high risk of food allergy: a protocol for a cross-sectional study

INTRODUCTION

Peanut allergies cause serious health problems worldwide. A strong finding has shown that the early introduction of peanuts into the diet of infants at high risk of food allergy reduces the prevalence of peanut allergy. Allergies to peanuts, sesame and tree nuts have been shown to coexist in 60% of cases and vary according to geographical location and dietary habits. Insights into the prevalence of nut and seed allergies in societies with varying consumption levels are essential for developing population-specific weaning guidelines. Understanding the age at which peanut allergy develops is paramount for successful early introduction strategies.

METHODS AND ANALYSIS

We will perform a cross-sectional study at two tertiary allergy centres in Warsaw and Bydgoszcz. Two hundred forty children aged 4-36 months with eczema or egg allergy will undergo an extensive assessment of their peanut, sesame and tree nut allergy status through skin testing, specific IgE measurements and oral food challenges. The primary outcome is the prevalence of peanut, sesame and tree nut allergies in Polish children at high risk of food allergy. Additionally, the timing of the development of peanut, sesame and tree nut allergies in the first 3 years of life in a high-risk population will be assessed.

ETHICS AND DISSEMINATION

The Ethics Committee of the Medical University of Warsaw, Poland approved this protocol (KB/86/2021). The results of this study will be submitted to a peer-reviewed journal no later than 1 year after data collection. The abstract will be presented at relevant national and international conferences.Although the authors may be able to commit to journal submission no later than 1 year after data collection, publication dates remain beyond their control.

TRIAL REGISTRATION NUMBER

NCT05662800.

Updates in Food Allergy Prevention in Children

Although significant evidence exists that feeding early has a role in the prevention of food allergy, this intervention in isolation may not be sufficient. Recent evidence highlights that early introduction of peanut specifically has had no significant impact on the populational prevalence of peanut allergy. Other factors that may contribute to food allergy prevention include regularity of ingestion once an allergen is introduced and consideration to the form in which the allergen is introduced (such as baked versus cooked egg). There are also many practicalities to early feeding and some discrepant viewpoints on these practicalities, which has led to poor implementation of early feeding strategies. In general, preemptive screening before food introduction is not recommended by most international allergy societies. Although there is little guidance to inform early introduction of allergens other than milk, egg, and peanut, the mechanism of sensitization is thought to be similar and there is no harm to early introduction. In terms of frequency and duration of feeding, there is little evidence to inform any concrete recommendations.

Cashew Allergy Prevalence and Sensitization in 1-Year-Old Infants

BACKGROUND

Cashew allergy is the most common tree nut allergy in Australia, but there are limited data on the population-level prevalence and risk factors.

OBJECTIVE

Describe the prevalence of cashew sensitization and allergy in 12-month-old infants and identify risk factors.

METHODS

Data were from the EarlyNuts cohort, a population-based sample of infants recruited in Melbourne, Australia. Families completed a questionnaire and infants underwent a skin prick test (SPT) to cashew. Infants with positive SPTs were offered food challenges. Questionnaires collected demographic data and allergy risk factors. Allergy outcomes were determined by challenge outcomes or a convincing history of an allergic reaction. We used weights to adjust estimated prevalence to reflect the distribution of risk factors among the combined sample of participants and nonparticipants.

RESULTS

We recruited 1,933 participants and identified 1,414 cashew allergy outcomes. Of these, 1.96% (95% CI, 1.28-2.99) had an SPT result of 3 mm or greater and 1.49% (95% CI, 0.91-2.44) were allergic to cashew. Infants with eczema or peanut allergy in the first year of life were more likely to be allergic to cashew (adjusted odds ratio = 5.75; 95% CI, 2.08-15.88; P = .001; and adjusted odds ratio = 19.30; 95% CI, 5.44-68.43; P < .001, respectively). Twenty-five percent of participants had cashew introduced before 12 months (95% CI, 22.7-27.8). There was no association between the timing of cashew introduction and cashew allergy.

CONCLUSIONS

To our knowledge, this is the first study describing the prevalence of and risk factors for cashew allergy in a population-based infant cohort. Eczema and peanut allergy were associated with an increased risk of cashew allergy. Few infants were introduced to cashew before age 12 months, which suggests that infant feeding guidelines have not yet translated to the earlier introduction of all allergens.

Developing a Prediction Model for Determination of Peanut Allergy Status in the Learning Early About Peanut Allergy (LEAP) Studies

BACKGROUND

The Learning Early About Peanut Allergy (LEAP) study team developed a protocol-specific algorithm using dietary history, peanut-specific IgE, and skin prick test (SPT) to determine peanut allergy status if the oral food challenge (OFC) could not be administered or did not provide a determinant result.

OBJECTIVE

To investigate how well the algorithm determined allergy status in LEAP; to develop a new prediction model to determine peanut allergy status when OFC results are not available in LEAP Trio, a follow-up study of LEAP participants and their families; and to compare the new prediction model with the algorithm.

METHODS

The algorithm was developed for the LEAP protocol before the analysis of the primary outcome. Subsequently, a prediction model was developed using logistic regression.

RESULTS

Using the protocol-specified algorithm, 73% (453/617) of allergy determinations matched the OFC, 0.6% (4/617) were mismatched, and 26% (160/617) participants were nonevaluable. The prediction model included SPT, peanut-specific IgE, Ara h 1, Ara h 2, and Ara h 3. The model inaccurately predicted 1 of 266 participants as allergic who were not allergic by OFC and 8 of 57 participants as not allergic who were allergic by OFC. The overall error rate was 9 of 323 (2.8%) with an area under the curve of 0.99. The prediction model additionally performed well in an external validation cohort.

CONCLUSION

The prediction model performed with high sensitivity and accuracy, eliminated the problem of nonevaluable outcomes, and can be used to estimate peanut allergy status in the LEAP Trio study when OFC is not available.

Defining the window of opportunity and target populations to prevent peanut allergy

BACKGROUND

Peanut allergy affects 1% to 2% of European children. Early introduction of peanut into the diet reduces allergy in high-risk infants.

OBJECTIVE

We aimed to determine the optimal target populations and timing of introduction of peanut products to prevent peanut allergy in the general population.

METHODS

Data from the Enquiring About Tolerance (EAT; n = 1303; normal risk; 3-year follow-up; ISRCTN14254740) and Learning Early About Peanut Allergy study (LEAP; n = 640; high risk; 5-year follow-up; NCT00329784) randomized controlled trials plus the Peanut Allergy Sensitization (PAS; n = 194; low and very high risk; 5-year follow-up) observational study were used to model the intervention in a general population. Peanut allergy was defined by blinded peanut challenge or diagnostic skin prick test result.

RESULTS

Targeting only the highest-risk infants with severe eczema reduced the population disease burden by only 4.6%. Greatest reductions in peanut allergy were seen when the intervention was targeted only to the larger but lower-risk groups. A 77% reduction in peanut allergy was estimated when peanut was introduced to the diet of all infants, at 4 months with eczema, and at 6 months without eczema. The estimated reduction in peanut allergy diminished with every month of delayed introduction. If introduction was delayed to 12 months, peanut allergy was only reduced by 33%.

CONCLUSIONS

The preventive benefit of early introduction of peanut products into the diet decreases as age at introduction increases. In countries where peanut allergy is a public health concern, health care professionals should help parents introduce peanut products into their infants' diet at 4 to 6 months of life.

Early Peanut Introduction in Primary Care: Evaluation of a Multicomponent Intervention

OBJECTIVE

To determine whether a multicomponent intervention focused on early peanut introduction was associated with a lower peanut allergy incidence in young children.

METHODS

The study cohort comprised all children born January 1, 2013 through December 31, 2018 receiving care at a large health care organization. Intervention activities occurred over 16 months and included provider educational programs, electronic health record tools, and new patient instructions. We used an interrupted time series design to assess whether peanut allergy incidence differed across 3 time periods (preintervention, interim, postintervention) among high- and low-risk children. The primary outcome was incident peanut allergy by age 24 months, defined as peanut allergy in the allergy field or active problem list plus a positive supportive test. Severe eczema and/or egg allergy presence defined high-risk. Because the study was conducted as part of routine care, it was not feasible to measure what counseling clinicians provided, or how and when parents fed their children peanut-containing foods.

RESULTS

In a cohort of 22,571 children, the percent with peanut allergy by age 24 months was 17.3% (116 of 671) among high-risk and 0.8% (181 of 21,900) among low-risk children. In multivariate analyses, the adjusted peanut allergy rate per 100 person-years was not significantly different across study periods among high-risk (9.6 preintervention, 11.7 interim, and 9.9 postintervention, P = .70) or low-risk (0.5 preintervention, 0.7 interim, and 0.5 postintervention, P = .17) children.

CONCLUSIONS

In a community-based setting, the incidence of peanut allergy did not decline following a multicomponent intervention focused on early peanut introduction.

Association Between Earlier Introduction of Peanut and Prevalence of Peanut Allergy in Infants in Australia

IMPORTANCE

Randomized clinical trials showed that earlier peanut introduction can prevent peanut allergy in select high-risk populations. This led to changes in infant feeding guidelines in 2016 to recommend early peanut introduction for all infants to reduce the risk of peanut allergy.

OBJECTIVE

To measure the change in population prevalence of peanut allergy in infants after the introduction of these new guidelines and evaluate the association between early peanut introduction and peanut allergy.

DESIGN

Two population-based cross-sectional samples of infants aged 12 months were recruited 10 years apart using the same sampling frame and methods to allow comparison of changes over time. Infants were recruited from immunization centers around Melbourne, Australia. Infants attending their 12-month immunization visit were eligible to participate (eligible age range, 11-15 months), regardless of history of peanut exposure or allergy history.

EXPOSURES

Questionnaires collected data on demographics, food allergy risk factors, peanut introduction, and reactions.

MAIN OUTCOME AND MEASURES

All infants underwent skin prick tests to peanut and those with positive results underwent oral food challenges. Prevalence estimates were standardized to account for changes in population demographics over time.

RESULTS

This study included 7209 infants (1933 in 2018-2019 and 5276 in 2007-2011). Of the participants in the older vs more recent cohort, 51.8% vs 50.8% were male; median (IQR) ages were 12.5 (12.2-13.0) months vs 12.4 (12.2-12.9) months. There was an increase in infants of East Asian ancestry over time (16.5% in 2018-2019 vs 10.5% in 2007-2011), which is a food allergy risk factor. After standardizing for infant ancestry and other demographics changes, peanut allergy prevalence was 2.6% (95% CI, 1.8%-3.4%) in 2018-2019, compared with 3.1% in 2007-2011 (difference, -0.5% [95% CI, -1.4% to 0.4%]; P = .26). Earlier age of peanut introduction was significantly associated with a lower risk of peanut allergy among infants of Australian ancestry in 2018-2019 (age 12 months compared with age 6 months or younger: adjusted odds ratio, 0.08 [05% CI, 0.02-0.36]; age 12 months compared with 7 to less than 10 months: adjusted odds ratio, 0.09 [95% CI, 0.02-0.53]), but not significant among infants of East Asian ancestry (P for interaction = .002).

CONCLUSIONS AND RELEVANCE

In cross-sectional analyses, introduction of a guideline recommending early peanut introduction in Australia was not associated with a statistically significant lower or higher prevalence of peanut allergy across the population.

Current insights: a systemic review of therapeutic options for peanut allergy

PURPOSE OF REVIEW

With increasing prevalence of peanut allergy (PA) globally and the greater risk of potential reactions occurring due to the leading role of nuts in food products, PA has become a significant public health concern over the past decade, affecting up to 5 million of the US adult population. This review details updates and advances in prevalence, diagnosis, and immunotherapies that have occurred over the past year.

RECENT FINDINGS

Therapeutic and diagnostic advances remain at the forefront of research and have continued to push the food allergy (FA) field forward to provide a promising role in the detection and treatment of PA. The FA field has researched significant advances in peanut immunotherapy, biomarker diagnosis, and quality of life (QoL) improvement.

SUMMARY

Given the burden and consequences for individuals with PA, these advances delivered in clinical practice can significantly improve the QoL of individuals with PA and their caregivers. Ongoing studies will continue to investigate long-term outcome measures of desensitisation and effective management plans tailored to the families' needs.

The natural history of peanut and egg allergy in children up to age 6 years in the HealthNuts population-based longitudinal study

BACKGROUND

Prospectively collected data on the natural history of food allergy are lacking.

OBJECTIVE

We examined the natural history of egg and peanut allergy in children from age 1 to 6 years and assessed whether a skin prick test (SPT) result or other clinical factors at diagnosis are associated with the persistence or resolution of food allergy in early childhood.

METHODS

The HealthNuts cohort consists of 5276 children who were recruited at age 1 year and have been followed prospectively. Children with food allergy at age 1 year (peanut [n = 156] or raw egg [n = 471] allergy ) and children who developed new sensitizations or food reactions after age 1 year were assessed for food sensitization and allergy (confirmed by oral food challenge when indicated) at the 6-year follow-up.

RESULTS

New-onset food allergy developed by age 6 years was more common for peanut (0.7% [95% CI = 0.5%-1.1%]) than egg (0.09% [95% CI = 0.03%-0.3%]). Egg allergy resolved more commonly (89% [95% CI = 85%-92%]) than peanut allergy (29% [95% CI = 22%-38%]) by age 6 years. The overall weighted prevalence of peanut allergy at age 6 years was 3.1% (95% CI = 2.6-3.7%) and that of egg allergy was 1.2% (95% = CI 0.9%-1.6%). The factors at age 1 year associated with persistence of peanut allergy were peanut SPT result of 8 mm or larger (odds ratio [OR] = 2.35 [95% CI 1.08-5.12]), sensitization to tree nuts (adjusted OR [aOR] = 2.51 [95% CI = 1.00-6.35]), and early-onset severe eczema (aOR = 3.23, [95% CI 1.17-8.88]). Factors at age 1 associated with persistence of egg allergy at age 6 were egg SPT result of 4 mm or larger (OR = 2.98 [95% CI 1.35-6.36]), other (peanut and/or sesame) food sensitizations (aOR = 2.80 [95% CI = 1.11-7.03]), baked egg allergy (aOR = 7.41 [95% CI = 2.16-25.3]), and early-onset severe eczema (aOR = 3.77 [95% CI = 1.35-10.52]).

CONCLUSION

Most egg allergy and nearly one-third of peanut allergy resolves naturally by age 6 years. The prevalence of peanut allergy at age 6 years was similar to that observed at age 1 year, largely owing to new-onset food peanut allergy after age 1 year. Infants with early-onset eczema, larger SPT wheals, or multiple food sensitizations and/or allergies were less likely to acquire tolerance to either peanut or egg.

Emerging developments in the forefront of peanut oral immunotherapy

PURPOSE OF REVIEW

Despite the COVID-19 pandemic, progress continued in the field of peanut oral immunotherapy over the past 12 to 18 months. Of importance, the first oral immunotherapy product for the treatment of peanut allergy was approved by the US Food and Drug Administration in January 2020.

RECENT FINDINGS

Suggested modifications to the practice of oral immunotherapy, some of which may have lasting impacts, were circulated as a result of the pandemic. New advances in pathophysiology, sustained unresponsiveness, quality of life, safety, and cost effectiveness were also published.

SUMMARY

During 2020, COVID-19 influenced the daily practice of allergy and immunology, with peanut oral immunotherapy being no exception. However, clinicians now have a FDA-approved treatment option for peanut allergy in children, a welcome development for a difficult disease. Future research is needed to clarify several knowledge deficits surrounding the best use of peanut OIT.

Age and eczema severity, but not family history, are major risk factors for peanut allergy in infancy

BACKGROUND

Whether to screen high-risk groups before early peanut introduction is controversial.

OBJECTIVE

We sought to determine the risk of peanut allergy (PA) before peanut introduction for infants with (1) moderate-severe eczema, (2) another food allergy (FA), and/or (3) a first-degree relative with peanut allergy (FH).

METHODS

Infants aged 4 to 11 months with no history of peanut ingestion, testing, or reaction and at least 1 of the above risk factors received peanut skin prick test and, depending on skin prick test wheal size, oral food challenge or observed feeding.

RESULTS

A total of 321 subjects completed the enrollment visit (median age, 7.2 months; 58% males); 78 had eczema only, 11 FA only, 107 FH only, and 125 had multiple risk factors. Overall, 18% of 195 with eczema, 19% of 59 with FA, and 4% of 201 with FH had PA. Only 1% of 115 with FH and no eczema had PA. Among those with eczema, older age (odds ratio [OR], 1.3; 95% CI, 1.04-1.68 per month), higher SCORing Atopic Dermatitis score (OR, 1.19; 95% CI, 1.06-1.34 per 5 points), black (OR, 5.79; 95% CI, 1.92-17.4 compared with white), or Asian race (OR, 6.98; 95% CI, 1.92-25.44) and suspected or diagnosed other FA (OR, 3.98; 95% CI, 1.62-9.80) were associated with PA.

CONCLUSIONS

PA is common in infants with moderate-severe eczema, whereas FH without eczema is not a major risk factor, suggesting screening only in those with significant eczema. Even within the first year of life, introduction at later ages is associated with a higher risk of PA among those with eczema, supporting introduction of peanut as early as possible.

A study to assess current approaches of allergists in European countries diagnosing and managing children and adolescents with peanut allergy

RATIONALE

Food allergy is documented to result in considerable morbidity, negative impact on quality of life, and substantial medical care costs. Although anecdotal data suggest widely varying practices in the diagnosis and management of food allergies, the diversity and relative frequency of these practices have not been documented.

METHODS

A questionnaire was developed evaluating allergists' management approaches of individuals with peanut allergy (PA) in Germany (DE), France (FR), and the United Kingdom (UK).

RESULTS

Here, we report the survey results from a total of 109 allergists from DE, FR and the UK. They reported to confirm PA at initial diagnosis using skin prick test (≥60%), while allergists from DE and FR reported using allergen-specific IgE testing more (>86%) compared to the UK (<50%). At initial diagnosis, oral food challenge was used less in DE (13%) and FR (14%) and very rarely in the UK (3%) to confirm diagnosis. Recognition of acute reactions, use of adrenaline auto-injectors and allergen avoidance were reported to be discussed with the patient/caregiver at the initial office visit by most allergists (>75%). Half of the responders reported assessing the patient's quality of life. 63% allergists reported retesting for PA resolution at a later date, with 45% allergists indicated to recommend ingestion of a normal serving of peanut regularly upon resolution. Lack of effective PA treatment was reported to be a 'very significant' barrier for optimal PA treatment, with allergists being less than 'moderately familiar' with data from clinical trials testing new treatments options for PA. Lastly, allergists stated that the severity of patient's PA ranked as the most important factor in their decision to recommend oral immunotherapy for PA treatment.

CONCLUSIONS

This survey provides essential insights into the practice of allergists and highlights some areas that would inform strategies for education and improving PA healthcare.

Factors Associated with Frequency of Peanut Consumption in Korea: A National Population-Based Study

Household peanut exposure via skin in infants with impaired skin barrier function is a risk factor for peanut allergy development. The aim of this study is to investigate the peanut consumption of Koreans using national representative data. We used data from the Korean National Health and Nutrition Examination Survey 2012-2016, consisting of data from 17,625 adults who complete the survey. Peanut intake was assessed using a 24-h recall method. Of the study population, 10,552 (59.9%), 6726 (38.2%), and 347 (1.9%) subjects were categorized into non-intake, intermittent intake, and frequent intake group, respectively. Ordered logistic regression models were used to examine the association between sociodemographic and dietary factors and the frequency of peanut intake. After adjusting for confounders, increasing age (adjusted odds ratio (aOR) 1.03; 95% confidence interval (CI) 1.03-1.04), higher education (high school graduates: aOR 1.75, 95 CI 1.39-2.19; higher than college: aOR 2.11, 95% CI 1.65-2.70), and prudent dietary scores in the second (aOR 1.71; 95% CI 1.47-1.99), third (aOR 2.53; 95% CI 2.16-2.97) and the fourth quartiles (aOR 3.72; 95%CI 3.16-4.40) were associated with a high frequency of peanut consumption. This information may be helpful not only in public health research for nutrition but also in personal management for the prevention of peanut allergy in Korea.

The economic impact of peanut allergies

The prevalence of peanut allergies, the most common food allergy in children, has tripled in the past 2 decades. Today, up to 2.5% of the pediatric population has been diagnosed with a peanut allergy. Peanut allergies result in significant medical, out-of-pocket, and opportunity costs to payers, parents, and employers. They are also a leading cause of food allergy-related deaths in children. Although there is evidence that peanut oral immunotherapy may be effective in reducing the severity of the allergy, such approaches require a long intervention with no standardized protocol available. The introduction of biologic compounds to treat peanut allergies has the potential to revolutionize how these patient cases are managed. Their anticipated high cost, however, raises several issues for payers as to how to integrate these new therapies into formularies and treatment continuums.

Severity of peanut allergy and the unmet gaps in care: a call to action

Peanut allergy is one of the most common food allergies in children, with a prevalence that has been increasing over the past several decades. The allergy is a type I, immunoglobulin E (IgE)-mediated reaction that commonly presents in childhood and can be associated with an anaphylactic response. There are many theories that attempt to explain the increasing prevalence, including dietary changes, improvements in hygiene, and intentional allergen avoidance. Diagnosis is made through a combination of a thorough patient history, peanut-specific serum-specific IgE levels, peanut skin-prick test, and, if necessary, an oral food challenge. Guidelines based on the landmark 2015 Learning Early About Peanut Allergy trial suggest that peanuts should be introduced into the diet as early as 4 to 6 months of age in infants who are at highest risk of developing peanut allergy. It is important for providers to recognize risk factors for the development of peanut allergy, identify associated clinical symptoms, and provide an accurate diagnosis of patients to effectively manage them and their families and prevent future reactions.

The National Institutes of Allergy and Infectious Diseases sponsored guidelines on preventing peanut allergy: A new paradigm in food allergy prevention

Peanut allergy is a significant public health problem without proven treatment or cure at present. In 2000, the American Academy of Pediatrics recommended that solid-food introduction be delayed in infants at high risk, including peanut introduction, until age 3 years. In 2008, the American Academy of Pediatrics revised these recommendations based on limited evidence of benefit and, instead, recommended solid-food introduction not be delayed past 4-6 months of life. In 2015, the Learning Early About Peanut Allergy study showed that early peanut introduction (between 4 and 11 months of life) was associated with a significant absolute and relative risk reduction in the development of peanut allergy compared with delayed introduction. Based on these findings, the National Institutes of Allergy and Infectious Diseases sponsored an expert panel to create an addendum to the 2010 Food Allergy Guidelines that specifically focuses on peanut allergy prevention. The addendum recommends that children with severe eczema, egg allergy, or both have peanut introduced as early as 4-6 months of life, after assessment by a trained allergy specialist. For children with mild-to-moderate eczema, peanut can be introduced at ∼6 months, without the need for specialist evaluation. For children with no eczema, peanut can be introduced in accordance with family and cultural preferences, without the need for specialist evaluation. Adherence to these clinical practice recommendations can help potentially reduce the number of cases of peanut allergy per year. However, this can only be accomplished with the cooperation of parents and health care providers who adhere to these recommendations.

Effect of Avoidance on Peanut Allergy after Early Peanut Consumption

BACKGROUND

In a randomized trial, the early introduction of peanuts in infants at high risk for allergy was shown to prevent peanut allergy. In this follow-up study, we investigated whether the rate of peanut allergy remained low after 12 months of peanut avoidance among participants who had consumed peanuts during the primary trial (peanut-consumption group), as compared with those who had avoided peanuts (peanut-avoidance group).

METHODS

At the end of the primary trial, we instructed all the participants to avoid peanuts for 12 months. The primary outcome was the percentage of participants with peanut allergy at the end of the 12-month period, when the participants were 72 months of age.

RESULTS

We enrolled 556 of 628 eligible participants (88.5%) from the primary trial; 550 participants (98.9%) had complete primary-outcome data. The rate of adherence to avoidance in the follow-up study was high (90.4% in the peanut-avoidance group and 69.3% in the peanut-consumption group). Peanut allergy at 72 months was significantly more prevalent among participants in the peanut-avoidance group than among those in the peanut-consumption group (18.6% [52 of 280 participants] vs. 4.8% [13 of 270], P<0.001). Three new cases of allergy developed in each group, but after 12 months of avoidance there was no significant increase in the prevalence of allergy among participants in the consumption group (3.6% [10 of 274 participants] at 60 months and 4.8% [13 of 270] at 72 months, P=0.25). Fewer participants in the peanut-consumption group than in the peanut-avoidance group had high levels of Ara h2 (a component of peanut protein)-specific IgE and peanut-specific IgE; in addition, participants in the peanut-consumption group continued to have a higher level of peanut-specific IgG4 and a higher peanut-specific IgG4:IgE ratio.

CONCLUSIONS

Among children at high risk for allergy in whom peanuts had been introduced in the first year of life and continued until 5 years of age, a 12-month period of peanut avoidance was not associated with an increase in the prevalence of peanut allergy. Longer-term effects are not known. (Funded by the National Institute of Allergy and Infectious Diseases and others; LEAP-On ClinicalTrials.gov number, NCT01366846.).

Peanut allergy in Mexican children: what is the effect of age at first consumption?

Studies suggest that children who start solid foods early are at risk for developing food allergies. Herein, we evaluated the effects of the introduction of peanuts to the diets of children on emerging peanut allergies. Children with allergic rhinitis and asthma were enrolled in the present study and evaluated in four stages. In the first stage, a clinical history was completed for all participants. In the second stage, skin tests were conducted to detect the sensitization to peanuts. In the third stage, the parents were interviewed about the peanut-eating habits of their children. In the fourth stage, children with a convincing history of allergy or a positive peanut skin test result were subjected to an open oral food challenge (OOFC). Three hundred children in four groups were included, 58.2% of the subjects were male, and the mean age was 7.3±3.9 years. The median age of first exposure to peanuts in patients with peanut allergies was greater than that in children without peanut allergies (2 years versus 1 year; p=0.009). The multivariate analysis, including only those children subjected to the OOFC, revealed that the consumption of peanuts after the age of ≥2 years is a risk factor for developing a peanut allergy (odds ratio=8.0, 95% confidence interval 1.3-50.0, p=0.026). The results of the present study showed that the late introduction of peanuts to children increases the risk of developing a peanut allergy.

Natural history of peanut allergy and predictors of resolution in the first 4 years of life: A population-based assessment

BACKGROUND

There are no prospectively collected data available on the natural history of peanut allergy in early childhood. Previous studies of predictors of tolerance development have been biased by failure to challenge high-risk children when IgE antibody levels are high, therefore potentially introducing bias to persistent allergy.

OBJECTIVES

We sought to describe the natural history of peanut allergy between 1 and 4 years of age and develop thresholds for skin prick test (SPT) results and specific IgE (sIgE) levels measured at age 1 and 4 years that have 95% positive predictive value (PPV) or negative predictive value for the persistence or resolution of peanut allergy.

METHODS

One-year-old infants with challenge-confirmed peanut allergy (n = 156) from the population-based, longitudinal HealthNuts Study (n = 5276) were followed up at 4 years of age with repeat oral food challenges, SPTs, and sIgE measurements (n = 103). Challenges were undertaken in all peanut-sensitized children at 1 and 4 years of age, irrespective of risk profile.

RESULTS

Peanut allergy resolved in 22% (95% CI, 14% to 31%) of children by age 4 years. Decreasing wheal size predicted tolerance, and increasing wheal size was associated with persistence. Thresholds for SPT responses and sIgE levels at age 1 year with a 95% PPV for persistent peanut allergy are an SPT-induced response of 13 mm or greater and an sIgE level of 5.0 kU/L or greater. Thresholds for SPT and sIgE results at age 4 years with a 95% PPV for persistent peanut allergy are an SPT response of 8 mm or greater and an sIgE level of 2.1 kU/L or greater. Ara h 2, tree nut, and house dust mite sensitization; coexisting food allergies; eczema; and asthma were not predictive of persistent peanut allergy.

CONCLUSION

These thresholds are the first to be generated from a unique data set in which all participants underwent oral food challenges at both diagnosis and follow-up, irrespective of SPT and sIgE results.

Randomized trial of peanut consumption in infants at risk for peanut allergy

BACKGROUND

The prevalence of peanut allergy among children in Western countries has doubled in the past 10 years, and peanut allergy is becoming apparent in Africa and Asia. We evaluated strategies of peanut consumption and avoidance to determine which strategy is most effective in preventing the development of peanut allergy in infants at high risk for the allergy.

METHODS

We randomly assigned 640 infants with severe eczema, egg allergy, or both to consume or avoid peanuts until 60 months of age. Participants, who were at least 4 months but younger than 11 months of age at randomization, were assigned to separate study cohorts on the basis of preexisting sensitivity to peanut extract, which was determined with the use of a skin-prick test--one consisting of participants with no measurable wheal after testing and the other consisting of those with a wheal measuring 1 to 4 mm in diameter. The primary outcome, which was assessed independently in each cohort, was the proportion of participants with peanut allergy at 60 months of age.

RESULTS

Among the 530 infants in the intention-to-treat population who initially had negative results on the skin-prick test, the prevalence of peanut allergy at 60 months of age was 13.7% in the avoidance group and 1.9% in the consumption group (P<0.001). Among the 98 participants in the intention-to-treat population who initially had positive test results, the prevalence of peanut allergy was 35.3% in the avoidance group and 10.6% in the consumption group (P=0.004). There was no significant between-group difference in the incidence of serious adverse events. Increases in levels of peanut-specific IgG4 antibody occurred predominantly in the consumption group; a greater percentage of participants in the avoidance group had elevated titers of peanut-specific IgE antibody. A larger wheal on the skin-prick test and a lower ratio of peanut-specific IgG4:IgE were associated with peanut allergy.

CONCLUSIONS

The early introduction of peanuts significantly decreased the frequency of the development of peanut allergy among children at high risk for this allergy and modulated immune responses to peanuts. (Funded by the National Institute of Allergy and Infectious Diseases and others; ClinicalTrials.gov number, NCT00329784.).

Food allergy: epidemiology and natural history

The prevalence of food allergy is rising for unclear reasons, with prevalence estimates in the developed world approaching 10%. Knowledge regarding the natural course of food allergies is important because it can aid the clinician in diagnosing food allergies and in determining when to consider evaluation for food allergy resolution. Many food allergies with onset in early childhood are outgrown later in childhood, although a minority of food allergy persists into adolescence and even adulthood. More research is needed to improve food allergy diagnosis, treatment, and prevention.

Peanut allergens

The earliest known evidence of peanut farming dates back 7,600 years. With a prevalence of roughly 1%, peanut allergy is a diagnostic and treatment challenge, but is also a very good model for studying all aspects of food allergy, including its molecular basis and pathomechanisms. Therefore, the very starting point for elucidating all these aspects is the identification of peanut allergens with subsequent clearing of their structure and their preparation as pure recombinant and/or natural allergens. This is the basis for in vitro diagnostic tests as well as the development of immunotherapeutic drugs. With regard to class I food allergy, peanut allergy affects by far the largest group of patients. In peanuts, 12 allergens have been identified and their molecular characteristics are described herein. Ara h 1, Ara h 3.01 and Ara h 3.02 (the former Ara h 4) belong to the cupin superfamily. The conglutins Ara h 2, Ara h 6 and Ara h 7, and the non-specific lipid transfer protein Ara h 9 belong to the prolamin superfamily. Ara h 5 (profilin) and Ara h 8 (Bet v 1-homologous protein) cause class II food allergies and are associated with inhalation allergy to pollen via the sequential and/or conformational similarity of molecules. Two peanut oleosins are listed as Ara h 10 and Ara h 11 and two defensins as Ara h 12 and Ara h 13 by the WHO/IUIS Allergen Nomenclature Subcommittee. The effect of the above-specified allergens has to be considered in the context of their matrix, which is influenced by processing factors and the individual's immune system.

[The prevalence of food allergy to peanut and hazelnut in children in Tomsk Region]

Food allergy to peanuts and nuts is an actual problem of practical health care, associated with significant prevalence of this disease, severe clinical symptoms and difficulty of diet organization. Purpose of the study--to study the prevalence of food allergy to peanut and hazelnut in Russian children, the investigation of clinical characteristics of this disease, and the mechanisms of sensitization to allergen components. The cross-sectional study was performed in the framework of the EuroPrevall (No FP6-2006-TTC-TU-5 Proposal 045879). The first stage was performed in random samples of primary schoolchildren aged 7-10 years (n = 13 010) from the Tomsk Region, Russia using a standardized questionnaire. The case-control sample was recruited for the second stage (n = 1288). Thus who reported adverse reactions to food in the screening stage were considered as cases (n = 652), children without reported reactions were controls (n = 636). The case-control stage included the completion of a clinical questionnaire, skin-prick test (ALK-Abelly, Spain), serum specific IgE measurement and component-resolved diagnostic: IgE measurement of allergen components of peanut (Ara h1, Ara h26, Ara h34, Ara h8), hazelnut (Cor a1, Cor a8, Cor a11) and birch allergen Bet v1 (ImmunoCAP, Phadia, Sweden). The prevalence of food allergy to peanut and hazelnut in children aged 7-10 years in the Tomsk region is 0.08 and 0.09%, respectively. The manifestation of the food allergy to nuts occurs in the preschool years, main reactions associated with allergy to nuts were oral allergy syndrome (75-80%), gastrointestinal disorders (60-80%) and itching skin rash (20-50%). Sensitization to birch is significantly correlated with the level of specific IgE to hazelnut (r = 0.53, p < 0.05) and peanut (r = 0.56, p < 0.05). Sensitization to heat-labile proteins peanut Ara h8 (12.3%) and hazelnut Cor a1 (8.8%) (homologues of Bet v1) dominates in the sample of children with food sensitization, that determines the cross-reactivity mechanism in the formation of food sensitization in the studied sample. The prevalence of allergies to peanut and hazelnut in Russia is much lower than in Europe and North America. Sensitization to these foods develops by the mechanism of cross-reactivity with birch pollen allergen. This type of sensitization determines mild clinical symptoms of allergy to hazelnut and peanut.

[Peanut allergy, not always the correct diagnosis]

BACKGROUND

Diagnosing peanut allergy in children is complicated. The clinical history can be difficult to interpret, measurement of peanut-specific immunoglobulin E (IgE) is of limited usefulness due to its poor specificity, and the gold standard (double-blind placebo-controlled food challenge) is time-consuming and labour-intensive, limiting its use in daily practice. Under-diagnosing peanut allergy is considered dangerous, because of serious reactions like anaphylaxis. As a result, there is a high probability of over-diagnosis of peanut allergy in the general population, leading to unnecessary peanut-free diets and parental anxiety.

CASE DESCRIPTION

We discuss three children diagnosed with peanut allergy, and describe the clinical and diagnostic considerations of peanut allergy. After a detailed history focusing on the reproducibility of objective symptoms after exposure, peanut allergy was excluded in two cases allowing normalization of the diet and reduction of patient and parental anxiety.

CONCLUSION

A detailed history, focusing on reproducible and objective symptoms, is helpful in confirmation or exclusion of the diagnosis 'peanut allergy' and can thus prevent unnecessary peanut-free diets.

IgE-mediated food allergy in children

Food allergy is a serious health issue affecting roughly 4% of children, with a substantial effect on quality of life. Prognosis is good for the most frequent allergens with almost all children outgrowing their allergy. However, the long-term implications for disease burden are substantial for children with persistent allergies (eg, peanuts, tree nuts, fish, and shellfish) and for those with high concentrations of milk, egg, and wheat IgE. Antigen avoidance has been the time-honoured approach both for prevention and treatment. However, findings from studies done in the past 5 years show that early contact with food can induce tolerance and desensitisation to foods. We review the epidemiology, natural history, and management of food allergy, and discuss the areas of controversy and future directions in research and clinical practice.

Parsing the peanut panic: the social life of a contested food allergy epidemic

As medical reports over the last decade indicate that food allergies among children are on the rise, peanut allergies in particular have become a topic of intense social debate. While peanut allergies are potentially fatal, they affect very few children at the population level. Yet, peanut allergies are characterized in medical and popular literature as a rising "epidemic," and myriad and broad-based social responses have emerged to address peanut allergy risk in public spaces. This analysis compares medical literature to other textual sources, including media reports, legislation, and advocacy between 1980 and 2010 in order to examine how peanut allergies transformed from a rare medical malady into a contemporary public health problem. I argue that the peanut allergy epidemic was co-constructed through interactions between experts, publics, biomedical categories, and institutions, while social reactions to the putative epidemic expanded the sphere of surveillance and awareness of peanut allergy risk. The characterization of the peanut allergy problem as an epidemic was shaped by mobility across social sites, with both discursive and material effects.

Peanut allergy diagnoses among children residing in Olmsted County, Minnesota

BACKGROUND

Peanut allergy is a major health concern, particularly in developed countries. Research indicates that as many as 2% of children are allergic to peanuts, which represents a 3-fold increase in diagnoses over the past 2 decades.

OBJECTIVE

This population-based descriptive study used the Rochester Epidemiology Project to estimate the prevalence in 2007 and annual incidence rates of peanut allergy diagnoses from 1999 to 2007 among children residing in Olmsted County, Minnesota.

METHODS

Residents of Olmsted County from January 1, 1999, through December 31, 2007, who received medical care at a Rochester Epidemiology Project facility and provided research authorization were eligible for the study. A medical chart review of 547 potential diagnoses resulted in 244 prevalent and 170 incident cases. Annual rates, crude and adjusted for age and sex, were standardized with the use of the indirect method to the Olmsted County population data in 1999. Incidence rate ratios were estimated with Poisson regression.

RESULTS

The prevalence in 2007 was 0.65%. Female children were less likely to be diagnosed than male children (incidence rate ratio = 0.18; 95% CI, 0.07-0.48). Children aged birth to 2 years were significantly more likely to be diagnosed than older children aged 3-17 years (incidence rate ratio = 0.001; 95% CI, 0.0004-0.004). A significant 3-fold increasing trend was observed in diagnoses over time from 2.05 cases per 10,000 children in 1999 to 6.88 cases per 10,000 in 2007.

CONCLUSIONS

Peanut allergies are an increasing concern in Olmsted County, Minnesota, as indicated by a 3-fold increase in diagnoses from 2.05 per 10,000 children in 1999 to 6.88 per 10,000 children in 2007.

Can we prevent food allergy by manipulating the timing of food exposure?

Prevention of food allergies by maternal and infant feeding practices serves as a simple, inexpensive approach to address the growing number of subjects with food allergies in comparison with any emerging interventional therapies for existing food allergies, such as oral immunotherapy. This article provides a careful evaluation of the rationale and existing data on the effect of timing of the introduction of food allergens (during pregnancy, lactation, and early childhood) on the development of specific food allergies.

Peanut allergy: an evolving clinical challenge

Peanut allergy is an IgE-mediated food allergy responsible for causing severe and occasionally fatal reactions in those sensitized to peanuts. The prevalence of peanut allergy appears to be on the rise worldwide, yet there are no therapeutics currently available that can alter the course of this condition. This article will review the epidemiology, pathogenesis, and clinical features of peanut allergy and discuss future possibilities in diagnostic and therapeutic modalities.