Quality and consistency of clinical practice guidelines on the prevention of food allergy and atopic dermatitis: Systematic review protocol

Background and aims

Allergy prevention strategies have gained significant traction as a means to attenuate the growing burden of allergic diseases over the past decade. As the evidence base for primary prevention of food allergy (FA) and atopic dermatitis (AD) is constantly advancing, clinical practice guideline (CPG) recommendations on interventions for FA and AD prevention vary in quality and consistency among professional organizations. We present a protocol for a systematic review of CPGs on primary prevention of FA and AD.

Methods

We will systematically review and appraise all CPGs addressing primary prevention of FA and AD and report our findings according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Electronic databases and manual website searches from January 2011 to March 2021 without language or geographical restrictions, and supplemented by author contact, will generate the list of potentially relevant CPGs to screen. Evaluation of the methodological quality, consistency, and global applicability of shortlisted CPGs will be performed by members of the Allergy Prevention Work Group of the World Allergy Organization (WAO) using the Appraisal of Guidelines for Research and Evaluation (AGREE) II and AGREE-REX (Recommendations EXcellence). instruments. Guideline contents, consistency, and quality of the recommendations will be summarised in tabular and narrative formats. We aim to present consolidated recommendations from international guidelines of the highest methodological quality and applicability, as determined by AGREE II and AGREE-REX.

Dissemination

This systematic review will provide a succinct overview of the quality and consistency of recommendations across all existing CPGs for FA and AD prevention, as well as crucial perspectives on applicability of individual recommendations in different geographical contexts. Results from this systematic review will be reported in a peer-reviewed journal. It will also inform a position statement by WAO to provide a practical framework to guide the development of future guidelines for allergy prevention worldwide.

Prospero registration number

CRD42021265689.

Oral immunotherapy for peanut allergy: The pro argument

Food allergy (FA) is a growing public health problem with personal, social, nutritional, and economic consequences. In the United States, it is estimated that 8% of children and 10.8% of adults have food allergies. Allergies to peanuts are particularly worrisome as unlike allergies to other allergenic foods, such as milk and egg, which are commonly outgrown by 5 or 10 years of age, 80% of peanut allergies persist into adulthood. The first drug for peanut allergy, Palforzia, was approved by the US Food and Drug Administration (FDA) in January 2020. For other food allergies, the current standard of care for the management of FA is suboptimal and is limited to dietary elimination of the offending allergen, vigilance against accidental ingestion, and treatment of allergic reactions with antihistamines and epinephrine. However, dietary avoidance can be challenging, and it is estimated that approximately 40% of patients with food allergies report at least one food allergy-related emergency department in their lifetime. Reactions, even from minimal exposures, can be life-threatening.

Oral immunotherapy (OIT) has been the best researched therapeutic approach for treating FA over the last decade, with clinical trials investigating its efficacy, safety, and ability to improve participants' quality of life (QoL). A number of studies and meta-analyses have shown that OIT treatment is effective in raising the threshold of reactivity to peanuts and other foods in addition to producing a measurable serum immune response to such therapy. Although OIT-related adverse events (AEs) are common during treatment, serious reactions are rare. In fact, while the majority of patients experience AEs related to dosing, most continue daily dosing in hopes of achieving protection against the culprit food. Moreover, the majority of participants report improvement of QoL after OIT and are positive about undergoing OIT. These results show patients’ commitment to OIT and their optimism regarding the benefits of treatment. As a first step in therapeutic options to protect from reactions to unintentional ingestion of allergenic foods, and importantly, to address the many psychosocial aspects of living with FA, OIT shows promise. Future research will focus on identifying optimal OIT regimens that maintain protection after therapy and allow for regular food consumption without allergic symptoms. Education and informed shared decision making between patients and providers are essential in optimizing current therapy regimens.

The predominance of seafood allergy in Vietnamese adults: Results from the first population-based questionnaire survey

Background

Food allergy (FA) is a serious, costly and growing health problem worldwide. FA occurs in both children and adults; however, there is a paucity of information on FA prevalence and its clinical features in the adult population, especially in Asia. We sought to assess the prevalence of FAs in Vietnamese adults and the distribution of offending food items among different regions throughout Vietnam.

Methods

A nationwide, cross-sectional, population-based survey was conducted among University students aged 16–50 years. We used a structured, anonymous questionnaire, which was modified from recently published FA epidemiologic studies and based on European Academy of Allergy and Clinical Immunology (EAACI) guidelines, to collect data on FA prevalence, clinical presentations, and implicated food groups. Statistical analysis was performed to generate the prevalence of self-reported and doctor-diagnosed FA and to examine the association of key environmental factors and FA incidence in this population.

Results

Of the 14,500 surveys distributed, a total of 9,039 responses were returned, resulting in a response rate of 62.4%. Among participants who reported food-induced adverse reactions, 48.0% have repeated reactions. 18.0% of the participants perceived FA symptoms, but less than half of them sought medical services for confirmation (37.9%). Stratifying for true FA symptoms, the prevalence of self-reported FA was 11.8% and of doctor-diagnosed FA, 4.6%. The most common doctor-diagnosed FA was to crustacean (3.0%; 95% CI, 2.6–3.3), followed by fish (1.6%; 95% CI, 1.3–1.8), mollusk (1.3%; 95% CI, 1.0–1.5) and beef (1.0%; 95% CI, 0.8–1.2). The prevalence of doctor-diagnosed FA differed among participants living in urban (6.5%) and rural regions (4.9%) (P < 0.001). Atopic family history was the strongest predictor for FA (odds ratio 8.0; 95% CI, 6.2–10.4).

Conclusions

Seafood allergy among adults is predominant in Vietnam, followed by beef, milk, and egg, while peanut, soy, and tree nut allergy are much less common. Populations in rural regions have considerably less FA; however, the protective environmental factors have yet to be identified.

Prevalence of food allergy among schoolchildren in Kuwait and its association with the coexistence and severity of asthma, rhinitis, and eczema: A cross-sectional study

Background

Food allergy (FA) is a common public health problem that affects both children and adults. Empirical knowledge of the burden of FA in Kuwait is limited. This study sought to estimate the prevalence of FA among schoolchildren in Kuwait and assess associations between FA and the coexistence and severity of asthma, rhinitis, and eczema.

Methods

Schoolchildren aged 11–14 years (n = 3,864) were enrolled in a cross-sectional study. Parents completed questionnaires regarding their children's early life exposures and clinical history of FA and allergic diseases. Study-defined FA was ascertained by a convincing clinical history. Associations were assessed using Poisson regression with robust variance estimation, and adjusted prevalence ratios (aPRs) and 95% confidence intervals (CIs) were estimated.

Results

The 12-month prevalence of study-defined FA was estimated to be 4.1% (154/3,738), with more girls being affected than boys (aPR = 1.44, 95% CI: 1.04–1.99). Egg (2.7%), fish (1.6%), shellfish (1.3%), peanut (1.3%), and tree nut (1.2%) were the most reported offending food allergens. Underweight and adiposity, cesarean section delivery, exposure to household dogs during infancy, and parental history of doctor-diagnosed FA were associated with an increased prevalence of study-defined FA. However, later birth order was associated with a reduced prevalence of study-defined FA. The prevalence of eczema only was higher in children with study-defined FA than in those without study-defined FA (aPR = 3.49, 95% CI: 2.37–5.14). In contrast, this association was not pronounced for children who had asthma only (aPR = 1.56, 95% CI: 0.94–2.57) or rhinitis only (aPR = 1.40, 95% CI: 0.86–2.28). Study-defined FA was associated with a 9.20-fold (95% CI: 4.50–18.78) higher prevalence of coexisting asthma, rhinitis, and eczema. Moreover, study-defined FA was associated with increased severity of symptoms of asthma, rhinitis, and eczema.

Conclusions

FA affects a considerable proportion of schoolchildren in Kuwait, and the most reported offending food allergens are similar to those reported in Western countries. Study-defined FA was associated with the coexistence and increased severity of asthma, rhinitis, and eczema, indicating that FA may link the comanifestations of allergic diseases and contribute to their chronicity and severity.