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Summary: Background and Objective: An infant's age at introduction of complementary solids may contribute to food allergy. We aimed to synthesize the literature on the association between age at introduction of complementary solids, excluding milk products, and food allergy and sensitization. Design: We searched the electronic databases PubMed and EMBASE (January 1946‐February 2017) using solid food, allergy and sensitization terms. Methods: Two authors selected papers according to inclusion criteria, identifying 16 cohort studies, 1 case‐control study and 8 randomized controlled trials (RCTs). Pooled effects across studies were estimated using random‐effects meta‐analysis. Results: Cohort studies—Introducing complementary solids at age ≥ 4 months vs <4 months was not associated with food allergy (OR 1.22; 95% CI, 0.76‐1.96) but was associated with food sensitization (OR 1.93; 95% CI 1.57‐2.38). First exposure from age 4 to 6 months vs <4 months was not associated with food allergy (OR 1.01; 95% CI, 0.64‐1.60) but was associated with food sensitization (OR 2.46; 95% CI 1.55‐3.86). Randomized controlled trials—Egg exposure from age 4 months was associated with reduced egg allergy (OR 0.63, 95% CI, 0.44‐0.90) and sensitization (OR 0.76, 95% CI, 0.51‐0.95). Peanut exposure from age 4 months compared to delayed exposure was associated with reduced peanut allergy (OR 0.28, 95% CI 0.14‐0.57). Conclusions: We found no evidence from observational studies that introducing solids before 4 months protected against food allergy, but there was evidence for protection against food sensitization. From RCTs, introducing egg from 4 to 6 months and peanut from 4 to 11 months reduced the risk of egg allergy, peanut allergy and egg sensitization. PROSPERO systematic review registry (CRD42016033473). [ABSTRACT FROM AUTHOR]

Background: While exposure to environmental greenness in childhood has shown mixed associations with the development of allergic disease, the relationship with food allergy has not been explored. We investigated the association between exposure to environmental greenness and challenge‐confirmed food allergy in a large population‐based cohort. Methods: The HealthNuts study recruited 5276 12‐month‐old infants in Melbourne, Australia, who underwent skin prick testing to peanut, egg, and sesame; infants with a detectable wheal underwent food challenges to determine food allergy status. Environmental greenness was estimated using the normalized difference vegetation index (NDVI) for five buffer zones around the infant's home address: at the home, 100 m, 500 m, 800 m, and 1600 m radial distances. Environmental greenness was categorized into 3 tertiles and mixed effects logistic regression models quantified the association between greenness and the risk of food allergy, adjusting for confounding and accounting for clustering at the neighborhood level. Results: NDVI data were available for n = 5097. For most buffer zones, medium and high greenness, compared to low greenness, was associated with an increased risk of peanut allergy (eg, 100 m tertile 2 aOR 1.89 95% CI 1.22–2.95, tertile 3 aOR 1.78 95% CI 1.13–2.82). For egg allergy, the effect sizes were smaller (100 m tertile 2 aOR 1.52 95% CI 1.16–1.97, tertile 3 aOR 1.38 95% CI 1.05–1.82). Socioeconomic status (SES) modified the association between greenness and peanut allergy, but not egg allergy; associations were apparent in the low SES group but not in the high SES group (p for interaction 0.08 at 100 m). Air pollution (PM2.5) also modified the associations between environmental greenness and food allergy, with associations present in high air pollution areas but not low (p for interaction at 100 m 0.05 for peanut and 0.06 for egg allergy.) Conclusion: Increased exposure to environmental greenness in the first year of life was associated with an increased risk of food allergy. Increased greenness may correlate with higher pollen levels which may trigger innate immune responses skewing the immune system to the Th2‐dependent allergic phenotype; additionally, some pollen and food allergens are cross‐reactive. Given the mixed data on greenness and other allergies, the relationship appears complex and may also be influenced by confounding variables outside those that were measured in this study. [ABSTRACT FROM AUTHOR]

Background: Previous systematic reviews have focused on associations between single time point measures of Body Mass Index (BMI) and asthma and allergic diseases. As BMI changes dynamically during childhood, examination of associations between longitudinal trajectories in BMI and allergic diseases is needed to fully understand the nature of these relationships. Objective: To systematically synthesise the association between BMI trajectories in childhood (0–18 years) and allergic diseases (asthma, eczema, allergic rhinitis, or food allergies outcomes). Design: We conducted a systematic review following the PRISMA guidelines, and two independent reviewers assessed the study quality using the ROBINS‐E and GRADE tools. A narrative synthesis was performed as the statistical heterogeneity did not allow a meta‐analysis. Data Sources: A search was performed on PubMed and EMBASE databases on 4th January 2023. Eligibility Criteria: Longitudinal cohort studies assessing the associations between childhood BMI trajectories and allergic diseases were included. Results: Eleven studies met the inclusion criteria with a total of 37,690 participants between 0 and 53 years of age. Ten studies examined asthma outcomes, three assessed association with allergic rhinitis, two assessed eczema, and one assessed food allergy. High heterogeneity and high risk of bias were observed. Overall, the quality of evidence was very low. Nevertheless, two consistent findings were identified: (1) a persistently high BMI between 6 and 10 years of age may be associated with an increased risk of asthma at 18 years and (2) a rapid increase in BMI in the first 2 years of life may be associated with subsequent asthma. Conclusions: Maintaining a normal BMI trajectory during childhood may reduce the risk of asthma. Future research that adequately addresses confounding and includes longer‐term follow‐up is needed. Moreover, additional studies examining potential associations with eczema, food allergies, and allergic rhinitis outcomes are needed. [ABSTRACT FROM AUTHOR]

Background: Oral immunotherapy (OIT) is a promising treatment for food allergies; however, safety is a concern. We synthesized evidence from the best randomized controlled trials (RCTs) on efficacy/safety of OIT for desensitization (DS) and remission (sustained unresponsiveness (SU)) in IgE mediated allergy to peanut, hen's eggs, and cow's milk. Body: We searched Pubmed, EMBASE, and Cochrane databases (Until Oct 22) identifying 16 eligible RCTs published in English measuring food allergy by food challenge at the beginning and at the end of the study. The Cochrane Risk of Bias tool was used to assess study quality. We found 18 eligible studies. There was evidence of efficacy for DS for all allergens: peanut (RR 11.32; 95% CI 5.93, 21.60, I2 49%, 8 studies); hen's egg (RR 4.67; 2.66, 8.21, I2 0%, 5 studies); cow's milk (RR 13.98; 3.51, 55.65, I2 0%, 4 studies) and evidence for SU for peanut (RR 7.74; 2.90, 20.69, I2 0%, 3 studies) and hen's egg (RR 6.91; 1.67, 28.57, I2 0%, 2 studies). Allergic events were increased with intervention, and risk of adrenaline use increased for peanut RR 2.96; 1.63, 5.35, I2 0%, 8 studies; egg RR 1.71; 0.42, 6.92, I2 0%, 6 studies; and milk RR 8.45; 2.02, 35.27, I2 0%, 4 studies. Conclusion: We found strong evidence that peanut, hen's egg, and cow's milk OIT can induce DS and some evidence for remission. There was a high risk of allergic reactions. Generalizability to the entire food allergic population is not known. [ABSTRACT FROM AUTHOR]

Objective: To summarise the associations between antenatal or early‐life blood vitamin D and the development of eczema/food allergy in childhood. Design: A systematic review and meta‐analyses were conducted to synthesize the published literature. Two reviewers independently performed the study selection and data extraction on Covidence. We assessed the risk of bias for observational studies by using the Newcastle‐Ottawa Scale and the Cochrane Risk of Bias tool for clinical trials. The certainty of the evidence was assessed using Grading of Recommendations, Assessment, Development and Evaluations (GRADE). Data sources We systematically searched PubMed and Embase from inception and April 2022. Eligibility criteria: Human studies that investigated prospective associations between antenatal or early‐life blood vitamin D levels, dietary intake or supplementation and childhood eczema/food allergy. Results: Forty‐three articles including six randomised controlled trials (RCTs) were included. Four RCTs of vitamin D supplementation during pregnancy showed no evidence of an effect on the incidence of eczema (pooled odds ratio [OR] = 0.85; 0.67–1.08, I2 = 6.7%, n = 2074). Three RCTs reported null associations between supplementation in pregnancy/infancy and food allergy. From six cohort studies, increasing cord blood vitamin D levels were associated with reduced prevalence of eczema at/close to age one (OR per 10 nmol/L increase = 0.89; 0.84–0.94, I2 = 0%, 2025 participants). We found no evidence of an association between maternal antenatal or infant vitamin D level or dietary intake and the development of food allergy or eczema in offspring. Conclusions: We found an association between higher vitamin D levels in cord blood and reduced risk of eczema in cohort studies. Further trials with maternal and infant supplementation are needed to confirm if vitamin D supplementation can effectively prevent eczema or food allergy in childhood. Systematic review registration: PROSPERO, No. CRD42013005559. [ABSTRACT FROM AUTHOR]

Background: IgE‐mediated food allergies have been linked to suboptimal naïve CD4 T (nCD4T) cell activation in infancy, underlined by epigenetic and transcriptomic variation. Similar attenuated nCD4T cell activation in adolescents with food allergy have also been reported, but these are yet to be linked to specific epigenetic or transcriptional changes. Methods: We generated genome‐wide DNA methylation data in purified nCD4 T cells at quiescence and following activation in a cohort of adolescents (aged 10–15 years old) with peanut allergy (peanut only or peanut + ≥1 additional food allergy) (FA, n = 29), and age‐matched non‐food allergic controls (NA, n = 18). Additionally, we assessed transcriptome‐wide gene expression and cytokine production in these cells following activation. Results: We found widespread changes in DNA methylation in both NA and FA nCD4T cells in response to activation, associated with the T cell receptor signaling pathway. Adolescents with FA exhibit unique DNA methylation signatures at quiescence and post‐activation at key genes involved in Th1/Th2 differentiation (RUNX3, RXRA, NFKB1A, IL4R), including a differentially methylated region (DMR) at the TNFRSF6B promoter, linked to Th1 proliferation. Combined analysis of DNA methylation, transcriptomic data and cytokine output in the same samples identified an attenuated interferon response in nCD4T cells from FA individuals following activation, with decreased expression of several interferon genes, including IFN‐γ and a DMR at a key downstream gene, BST2. Conclusion: We find that attenuated nCD4T cell responses from adolescents with food allergy are associated with specific epigenetic variation, including disruption of interferon responses, indicating dysregulation of key immune pathways that may contribute to a persistent FA phenotype. However, we recognize the small sample size, and the consequent restraint on reporting adjusted p‐value statistics as limitations of the study. Further study is required to validate these findings. [ABSTRACT FROM AUTHOR]

Background: Australia has one of the highest prevalence of childhood food allergy in the world, but there are no data on its economic burden in Australia. Methods: We used data from the HealthNuts study, a population‐based longitudinal study undertaken in Melbourne, Australia. Infants were recruited at age 12 months between Sept 2007 and Aug 2011 with food allergy diagnosed using oral food challenges. Health care costs of out‐of‐hospital services were collected through data linkage to Australia's universal health insurance scheme Medicare. Two‐part model was used to compare costs after controlling for potential confounders. Results: 2919 children were included, and 390 (13.4%) had challenge‐confirmed food allergy at age 1 year. Compared with children without food allergy, children with food allergy had significantly higher costs for GP visits, specialist visits, tests, and prescriptions in the first four years of life. The total Medicare cost associated with food allergy from age 1 to 4 years was estimated to be AUD$889.7 (95% CI $566.1–$1188.3) or €411.0 (95% CI €261.5–€549.0) per child. This was projected into an annual Medicare cost of AUD$26.1 million (95% CI $20.1–$32.3 million) or €12.1 (95% CI €9.3–€14.9 million) based on population size in 2020. Conclusions: Childhood food allergy causes considerable Medicare costs for out‐of‐hospital services in the first four years after birth in Australia. These findings can help anticipate the financial impact on the health care system associated with childhood food allergy, act as a useful costing resource for future evaluations, and inform management of childhood food allergy internationally. [ABSTRACT FROM AUTHOR]

Background: While the relationship between pollen and respiratory allergies is well‐documented, the role of short‐term pollen exposure in food allergy and eczema flares has not previously been explored. We aimed to investigate these associations in a population‐based sample of children. Methods: We investigated 1‐ (n = 1108) and 6‐year‐old (n = 675) children in the grass pollen season from the HealthNuts cohort. Grass pollen concentrations were considered on the day of testing (lag 0), up to three days before (lag 1‐lag 3) and cumulatively (lag 0–3). Associations between grass pollen and food skin‐prick test reactivity (SPT ≥ 2 mm at age 1 year and ≥ 3 mm at age 6 years), eczema flares, challenge‐confirmed food allergy, reaction threshold to oral food challenges (OFC), and serum food‐specific IgE levels were analyzed using either logistic or quantile regression models. Atopy and family history of allergic disease were considered as potent effect modifiers. Results: Grass pollen at lag 0–3 (every 20 grains/m3 increase) was associated with an up to 1.2‐fold increased odds of food SPT reactivity and eczema flares in 6‐year‐olds. In 1‐year‐olds, the associations were only observed for peanut in those with a family history of food allergy. Increasing grass pollen concentrations were associated with a lower reaction threshold to OFC and higher serum IgE levels in peanut‐allergic 1‐year‐olds only. Conclusion: Increasing grass pollen concentration was associated with increased risk of food SPT reactivity and eczema flares in children. The associations in peanut‐allergic infants may be related to immune activation and/or peanut and grass pollen cross‐reactivity leading to a lower reaction threshold. [ABSTRACT FROM AUTHOR]

Background: The heterogeneity of development and progression of eczema suggests multiple underlying subclasses for which aetiology and prognosis may vary. A better understanding may provide a comprehensive overview of eczema development and progression in childhood. Thus, we aimed to determine longitudinal eczema subclasses based on assessments and identify their associations with risk factors and allergic outcomes. Methods: A total of 619 participants with a family history of allergic disease were assessed at 24 time‐points from birth to 12 years. At each time, eczema was defined as the report of current rash treated with topical steroid‐based preparations. Longitudinal latent class analysis was used to determine eczema subclasses. Subsequent analyses using regression models assessed the associations between eczema subclasses and potential risk factors and allergic outcomes at 18‐ and 25‐year follow‐ups (eczema, allergic rhinitis, asthma and allergic sensitization). Results: We identified five eczema subclasses 'early‐onset persistent', 'early‐onset resolving', 'mid‐onset persistent', 'mid‐onset resolving' and 'minimal eczema'. Filaggrin null mutations were associated with the early‐onset persistent (OR = 2.58 [1.09–6.08]) and mid‐onset persistent class (OR = 2.58 [1.32–5.06]). Compared with 'minimal eczema', participants from early‐onset persistent class had higher odds of eczema (OR = 11.8 [5.20–26.6]) and allergic rhinitis (OR = 3.13 [1.43–6.85]) at 18 and at 25 years eczema (OR = 9.37 [3.17–27.65]), allergic rhinitis (OR = 3.26 [1.07–9.93]) and asthma (OR = 2.91 [1.14–7.43]). Likewise, mid‐onset persistent class had higher odds of eczema (OR = 2.59 [1.31–5.14]), allergic rhinitis (OR = 1.70 [1.00–2.89]) and asthma (OR = 2.00 [1.10–3.63]) at 18 and at 25 years eczema (OR = 6.75 [3.11–14–65]), allergic rhinitis (OR = 2.74 [1.28–5.88]) and asthma (OR = 2.50 [1.25–5.00]). Allergic and food sensitization in early life was more common in those in the persistent eczema subclasses. Conclusion: We identified five distinct eczema subclasses. These classes were differentially associated with risk factors, suggesting differences in aetiology, and also with the development of allergic outcomes, highlighting their potential to identify high‐risk groups for close monitoring and intervention. [ABSTRACT FROM AUTHOR]

HealthNuts is a single-centre, multi-wave, population-based longitudinal study designed to assess prevalence, determinants, natural history and burden of allergy (particularly food allergy) in the early years of life. It is novel in the use of serial food challenge measures within its population frame to confirm food allergy. The cohort comprises 5276 children initially recruited at age 12 months from council-run immunization sessions across Melbourne, Australia. As well as parent-completed questionnaires and researcher-observed eczema status, all infants underwent skin-prick testing to egg, peanut, sesame and either cow's milk or shellfish, and those with detectable wheals underwent food challenges to determine clinical allergy. In wave 2, conducted at age 4 years, validated questionnaires collected data on asthma, allergic rhinitis (hay fever), eczema and food allergies. Food challenges were repeated in children previously identified as food allergic to determine resolution. In wave 3, all children (irrespective of food allergy status) were invited for clinical assessment at age 6 years, including lung function, physical measurements, skin-prick testing to foods and aeroallergens and food challenges if food sensitized. Biological specimens (blood, cheek swabs) were collected at each wave for ancillary immunological, genetic and epigenetic studies. Applications to access data and/or samples can be submitted to [katrina.allen@mcri.edu.au]. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Context It has been hypothesized that a mother's diet during pregnancy may modulate her offspring's immune system development and lead to development of allergic diseases among offspring. However, the evidence for this is unclear and inconclusive. Objective This systematic review was undertaken to examine the weight of evidence for causality from cohort studies on the association between maternal free sugar intake during pregnancy and development of allergies in offspring. Data Sources Using a systematic search strategy, PubMed, SCOPUS, and Web of Science databases were searched from inception to May 2020. Data Extraction For the reporting of this systematic review, the PRISMA guideline was followed. Studies examining maternal sugar consumption during pregnancy (using self-reported data) and the development of allergic diseases among offspring (infancy to 5 years) were included. Data Analysis The Newcastle–Ottawa Scale quality assessment tool was used to assess the study quality. Meta-analysis was conducted using a random-effects model to synthesize the findings. Of 159 publications identified from the search, 5 articles with 4 unique cohort studies were included in this systematic review. The limited meta-analysis showed that a mother's increased free sugar intake during pregnancy was associated with an increased risk of developing asthma in offspring (odds ratio 1.07 [95% CI, 1.00 to 1.14; I2 = 0%]). High free sugar intake by the mother during pregnancy was also associated with increased odds of offspring (to age 7.7 years) developing other common allergies, including allergic rhinitis, atopy and eczema, wheeze, and food allergies. Conclusion From the limited evidence, this review suggests that high free sugar consumption during pregnancy may be associated with the development of allergies in offspring. Clinical guidelines and public health policy recommendations for maternal diet in pregnancy should include advice about reducing free sugar intake due to a possible association with allergies in offspring. However, recommendations should be made with caution considering other maternal and fetal risk factors. [ABSTRACT FROM AUTHOR]

Birth during pollen seasons may influence food allergy risk but no study has assessed pollen exposure. Using the HealthNuts population-based cohort of 5276 infants, we assessed grass pollen exposures, in utero and up to the first 6 months of life, on hen's egg, sesame and peanut allergy outcomes at 12 months. Cumulative pollen exposure in the first 7 days of life increased risk of peanut sensitization aMOR (adjusted multinomial odds ratio) = 1.21 (95% CI: 1.01–1.44). Exposure between first 4–6 months of life increased risk of hen's egg aMOR = 1.02 (95% CI: 1.004–1.04) and sensitization to all foods aMOR = 1.02 (95% CI: 1.003–1.04). Grass pollen exposure was associated with food challenge diagnosed food allergy, but only among infants with a maternal history of food allergy. Exposure to grass pollen in the intrauterine period and infancy may be important but more studies are needed to replicate these findings. [ABSTRACT FROM AUTHOR]

Background: Early life body mass index (BMI) trajectories influence the risk of asthma at 18 years of age. However, it is unclear if these are also associated with other allergic diseases. Objectives: We investigated the associations between BMI trajectories and subsequent allergic rhinitis, eczema and food sensitisation/allergies. Methods: Parent‐reported anthropometric data were collected 18 times in the first two years of life from a cohort of 620 participants in a high‐risk cohort. Group‐based trajectory modelling was applied to develop BMI trajectories. Associations between trajectories and allergic rhinitis, eczema and food sensitisation at 6, 12 and 18 years of age were assessed using logistic regression models. Potential effect modifications by parental allergic disease, sex and allocated infant formula were assessed. Results: We identified five BMI trajectories: average, below average, persistently low, early low and catch up, and persistently high. None showed an association with allergic rhinitis. In participants with maternal allergic rhinitis, 'early‐low and catch‐up' (OR = 2.83;95%CI 1.34‐5.96, Pint = 0.05) and 'below average' trajectories (OR = 2.39; 1.18‐7.23, Pint = 0.02) were associated with allergic rhinitis at 18 years of age compared with the average trajectory. No associations were observed with eczema or food sensitisation. Conclusion: Infants with early‐low and catch‐up, or below average BMI growth, were at increased risk of allergic rhinitis at 18 years if they had a mother with allergic rhinitis. These results require replication, but suggest that interactions between poor intrauterine growth, failure to thrive and maternal allergies may influence the risk of allergic rhinitis. [ABSTRACT FROM AUTHOR]

Aim: Food establishments that sell non‐packaged foods are not required to have a food label directly on the food product detailing the ingredients. This practice could increase the risk of anaphylaxis among individuals with food allergy. The aim of the study is to understand whether anaphylaxis occurs commonly in individuals with food allergy as a consequence of eating food products purchased from food establishments. Methods: We undertook an anonymous on‐line cross‐sectional survey of food allergic individuals over a 9‐month period. Anaphylaxis was defined as reported symptoms consistent with the Australasian Society of Clinical Immunology and Allergy definition of anaphylaxis. Results: A total of 268 responses were received over the study period and 264 consented and completed the questionnaire. Among our survey participants, the rate of anaphylaxis to food purchased from establishments was 27% (n = 67/246, 95% confidence interval 21.8–33.3%). Of those who reported an anaphylaxis (n = 67), 87% reported informing staff of their/their dependents food allergy/s. Most (81%) reported that they would like to see additional information, such as listing of allergen information next to dishes on the menu and 61% reported that staff pro‐actively asking about food allergies would be beneficial. Conclusion: Anaphylaxis from food purchased at food establishments is not uncommon despite a high proportion of individuals declaring their food allergy to staff. Consumers with food allergy would like to see allergen information listed on the menus and for staff to proactively enquire about food allergies. A food allergen matrix that is regularly checked/updated so staff and consumers have easy access to information on menu items and common allergens is required. [ABSTRACT FROM AUTHOR]

Background: In Western countries, Asian children have higher food allergy risk than Caucasian children. The early‐life environmental exposures for this discrepancy are unclear. We aimed to compare prevalence of food allergy and associated risk factors between Asian children in Singapore and Australia. Methods: We studied children in the Growing Up in Singapore Towards healthy Outcomes (GUSTO) birth cohort (n = 878) and children of Asian ancestry in the HealthNuts cohort (n = 314). Food allergy was defined as a positive SPT ≥3 mm to egg or peanut AND either a convincing history of IgE‐mediated reaction at 18 months (GUSTO) or a positive oral food challenge at 14‐18 months (HealthNuts). Eczema was defined as parent‐reported doctor diagnosis. Results: Food allergy prevalence was 1.1% in Singapore and 15.0% in Australia (P<0.001). Egg introduction was more often delayed (>10 months) in Singapore (63.5%) than Australia (16.3%; P<0.001). Prevalence of early‐onset eczema (<6 months) was lower in Singapore (8.4%) than Australia (30.5%) (P<0.001). Children with early‐onset eczema were more likely to have food allergy than those without eczema in Australia [aOR 5.11 (2.34‐11.14); P<0.001] and Singapore [aOR4.00 (0.62‐25.8); P = 0.145]. Conclusions: Among Asian children, prevalence of early‐onset eczema and food allergy was higher in Australia than Singapore. Further research with larger sample sizes and harmonized definitions of food allergy between cohorts is required to confirm and extend these findings. Research on environmental factors influencing eczema onset in Australia and Singapore may aid understanding of food allergy pathogenesis in different parts of the world. [ABSTRACT FROM AUTHOR]

Background: Although there is ongoing debate regarding the impact of early postnatal exposure to antibiotics on the development of asthma, the possibility that antibiotic exposure may impair lung function has not previously been examined. Furthermore, it is unclear if specific types of antibiotics may have a greater effect, or if children with genetic mutations in the oxidative stress response glutathione S-transferase (GST) superfamily may be at greater risk.Methods: Parent-reported data of childhood antibiotic use from birth to 2 years, including type and indication, were collected from a birth cohort of 620 infants with a family history of allergy. Spirometry was performed at age 12 and 18 years, and results are presented as z scores. Participants were genotyped for GST-P, GST-M, and GST-T polymorphisms. Linear regression models were used to investigate the associations while adjusting for confounding factors.Results: Neither increasing days of exposure nor earlier exposure to antibiotics was associated with reduced FEV1 (at 18 years, per doubling of days of exposure = -0.03 z score units; 95% CI, -0.11 to 0.04) or FVC (< 0.01; 95% CI, -0.08 to 0.07). There was no evidence that GST-risk polymorphisms (M1, P1, and T1) increased susceptibility, and specific types of antibiotics also did not increase risk of lung function deficits.Conclusions: Increasing exposure to oral antibiotics in early postnatal life was not associated with reduced lung function in children with a family history of allergic diseases. Although unwarranted use of antibiotics in children should be minimized, concerns regarding long-term lung health should not be a driving influence for this rationalization of use. [ABSTRACT FROM AUTHOR]

Objective: Asthma and allergic diseases are poorly described in rural areas. The objective of this study was, therefore, to determine the prevalence of wheezing, asthma, and other allergic disorders among children living in regional and rural Tasmania. Methodology: Data from a cross-sectional survey using standardized questionnaires of asthma, allergic conditions and food allergies were collected from 39 primary schools across North West Tasmania. We enrolled 1075 children between 6 and 8 years. The main outcomes were prevalences of wheezing, asthma, and other allergic disorders further stratified by sex and indigenous status. Results: Baseline characteristics were as follows: median age 8.1 years (IQR: 7.6, 8.7) with equal sex distribution, most (80.1%) attended public schools and 11.0% identified as indigenous. We report prevalences of current wheezing (22.7%), allergic rhinoconjunctivitis (16.3%) and atopic eczema (16.6%), with higher prevalences among boys (except eczema). Food allergies were reported in 8.6% and food-related anaphylaxis in 1.6% of the sample. Indigenous children had significantly higher prevalence of current wheezing (indigenous 31.1% versus non-indigenous 21.6%; p = 0.02). Further, children with current wheezing and no asthma diagnosis, had similar prevalence of other atopic diseases (hayfever 31.4%, eczema 44.0%, and food reaction 23.2%) compared with diagnosed asthmatics, although likely shared the illness. Conclusions: Childhood asthma is more prevalent in regional Tasmania compared with national estimates, especially among indigenous children. This appears not to be driven by an allergic response. Also, a significant proportion of children are likely to have undiagnosed asthma which has implications for rural health service delivery. [ABSTRACT FROM AUTHOR]

Background: IgE‐mediated egg allergy presents as one of the most common food allergies in children. Measurement of egg white specific IgE (sIgE) levels in serum or skin prick test has been shown to be a poor predictor of clinical allergy to raw egg white, and also to baked or cooked egg. Recent developments in component resolved diagnostic (CRD) technology have enabled us to improve the way in which we diagnose and predict peanut allergy by examining IgE specificity to individual peptides. Objectives: We aimed to investigate whether egg CRD could improve current methods to diagnose various egg allergy phenotypes as well as predict the development of tolerance to egg. Methods: Using the HealthNuts cohort of food challenge‐proven egg allergic and egg‐sensitized and egg‐tolerant, age‐matched 12‐month infants with longitudinal follow‐up at 2 and 4 years (n = 451), we measured serum egg white, Gal d 1, 2, 3 and 5 sIgE using ImmunoCAP. Results: Gal d 1 sensitization increased the risk of persistent egg allergy by 2.5‐fold. The production of sIgE to all four egg allergens (Gal d 1, 2, 3 or 5) increased the risk of having persistent raw egg allergy fourfold (OR 4.19 (95% CI: 1.25‐14.07). We did not find any improvements of using Gal d 1, 2, 3 or 5 to diagnose current egg allergy compared to egg white sIgE. Conclusion: Sensitization to multiple egg allergens Gal d 1, 2, 3 or 5 may be a prognostic marker that could be useful for patient management and identifying individuals at risk of developing persistent egg allergy. Sensitisation to Gal d 1 increases the risk of persistent egg allergy later in life (OR 2.5). Sensitisation to any of the 3 or 4 major egg allergens Gal d 1, 2, 3 or 5, increases the risk of persistent egg allergy (OR 4.19). The use of egg CRD does not improve the accuracy of egg allergy diagnosis compared to current whole egg sIgE 95% PPV. [ABSTRACT FROM AUTHOR]

Aim: To determine whether infant-feeding practices, including duration of exclusive breastfeeding and use of partially hydrolysed formula, modify the risk of developing infant food allergy.Methods: In an observational population-based study, 1 year olds were recruited from community immunisation clinics in Melbourne, Australia. Parent-reported data on infant-feeding practices and potential confounders were collected prior to infant skin prick testing for four food allergens. Sensitised infants attended hospital-based oral food challenges to establish food allergy status. Multiple logistic regression was used to investigate associations between breastfeeding and formula-feeding and infant food allergy adjusting for possible confounding variables.Results: A total of 5276 (74% response) infants participated. Of the 4537 for whom food allergy status was determined, 515 (11.3%) were food allergic (challenge-proven in the context of skin prick testing positive (≥2 mm)). After adjusting for confounding variables, there was no association between duration of exclusive breastfeeding and food allergy. Use of partially hydrolysed formula did not reduce the risk of food allergy compared with cow's milk formula in the general population (adjusted odds ratios 1.03 (confidence interval 0.67-1.50)).Conclusion: Duration of exclusive breastfeeding and use of partially hydrolysed formula were not associated with food allergy at 1 year of age in this large population-based study. These findings have implications for population-based infant-feeding guidelines and do not support the use of partially hydrolysed formula for food allergy prevention. [ABSTRACT FROM AUTHOR]

Background Longitudinal data on the natural history of food sensitization beyond early childhood are scarce. We aimed to investigate the natural history of milk, egg and peanut sensitization from infancy to 18 years and assess whether early food sensitization predicted adolescent food allergy. Methods Sensitization to cow's milk, hen's egg and peanut was measured by skin prick testing at ages 6 months, 1, 2, 12 and 18 years in a high-risk allergy birth cohort (n = 620). Generalized additive models investigated interactions with sex, eczema and aeroallergen sensitization in infancy. Logistic regression assessed the relationships between early food sensitization and adolescent sensitization and probable food allergy up to 18 years. Results The prevalence of egg and peanut sensitization peaked at 12 months, while milk sensitization peaked at both 1 and 12 years. Boys with early eczema had the highest prevalences of milk and egg sensitization throughout follow-ups. However, neither sex nor eczema influenced the prevalence of peanut sensitization over time. New onset food sensitization beyond the age of 2 was observed in 7% of participants. Food sensitization at 12 months was associated with increased risk of adolescent food sensitization and adolescent probable food allergy, with sensitization to more than one food allergen had the strongest predictor. Conclusions Food sensitization prevalence is highest in infancy and declines after 12 months of age. Boys with early-life eczema have the highest prevalence of milk and egg sensitization. Food sensitization at 12 months can predict children at greater risk of adolescent sensitization and probable food allergy at 12 and 18 years. [ABSTRACT FROM AUTHOR]

Aim: To report the cumulative incidence, health-seeking behaviour and medical intervention of infants with gastro-oesophageal reflux (GOR) in the first year of life.Methods: The HealthNuts study is a longitudinal, population-based study. At 12 months of age, infants underwent skin prick testing to food allergens, including cows milk. Parents completed a questionnaire on GOR symptoms, food allergy and treatments. Factors associated with seeking health care for infants with GOR were modelled using logistic regression.Results: Of 4674 infants, parents reported GOR in 1054 (23%; 95% confidence interval (CI) 21.4-23.8). Parents consulted a medical practitioner in 662 (64%) cases. Symptoms commenced in the first month in 411 (48%) and resolved within 6 months in 703 (75%) infants. Factors associated with doctor consultation for GOR were prematurity (adjusted odds ratio (aOR) 1.94; 95% CI 1.43-2.63) and family history of atopy (aOR 1.64; 95% CI 1.1-2.43). Eight per cent of infants (371/4674; 95% CI 7.2-8.7) received anti-reflux medication and 6% (296/4674; 95% CI 5.7-7.1) changed formula. Parents were more likely to seek treatment if they perceived their infant to be unsettled (aOR 2.55; 95% CI 1.26-5.17) and if the duration of GOR was prolonged (aOR 3.36 for symptoms >6 months; 95% CI 1.83-6.17).Conclusions: In the first year of life, approximately 14% of the population seek medical advice for GOR symptoms. The use of anti-reflux medication in the general community remains high, despite the absence of evidence that it is appropriate or effective for uncomplicated GOR. [ABSTRACT FROM AUTHOR]

Reports suggest that unintended food allergen presence in processed foods caused by allergen cross-contact (i.e. food comes into contact with another food) may be the leading cause of contamination resulting in adverse reactions. The aim of this study was to examine factors which contribute to undeclared allergens being present in processed foods in Australia, by examining food recalls. There is a need for improved packaging practices to minimise foods with undeclared allergens and increase food safety for food allergic consumers. [Extracted from the article]