Jennifer J. Koplin

Objective: To examine the overall incidence rate and trends in emergency department (ED) presentations related to asthma and allergic diseases in regional Australia with a particular focus on First Nations Australians. Methods: A retrospective analysis of data from the Emergency Department Information System. Methods: This study used data from 12 public hospitals in Central Queensland, Australia, a region encompassing regional, rural and remote outback areas. Methods: A total of 813 112 ED presentations between 2018 and 2023. Methods: Asthma and allergic diseases were identified using the International Classification of Diseases-Tenth Revision-Australian Modification codes. Results: There were 13 273 asthma and allergic disease-related ED presentations, with an overall prevalence of 1.6% (95% CI 1.6, 1.7). There was a significantly higher incidence rate of asthma and allergic disease-related ED presentations among First Nations Australians at 177.5 per 10 000 person-years (95% CI 169.3, 186.0) compared with 98.9 per 10 000 person-years (95% CI 97.2, 100.8) among Australians of other descents. The incidence rates, with corresponding 95% CIs, of the four most common cases among First Nations Australians and Australians of other descents, respectively, were as follows: asthma (87.8 (82.0, 93.8) and 40.2 (39.0, 41.3)), unspecified allergy (55.3 (50.8, 60.2) and 36.0 (34.9, 37.1)), atopic/allergic contact dermatitis (17.1 (14.6, 19.9) and 10.6 (10.0, 11.2)) and anaphylaxis (7.2 (5.6, 9.1) and 6.2 (5.7, 6.6)). Conclusions: Our findings highlight a significantly higher rate of asthma and allergic disease-related ED presentations among First Nations Australians compared with Australians of other descents. This underscores the urgent need for targeted healthcare interventions integrating culturally appropriate approaches, alongside additional research to understand causality.

Background: Peanut allergy consumes a significant volume of oral food challenges (OFC) in the diagnosis of food allergy. Two-step diagnostic algorithms involving both SPT and Ara h 2 sIgE demonstrate increased accuracy of diagnosis in modelled studies compared to peanut skin prick test (SPT) or sIgE to whole peanut, which should result in fewer OFCs. In 2015, The Royal Children's Hospital, Australia (RCH) implemented a clinical guideline using a two-step algorithm incorporating peanut SPT (3-8 mm) followed by sIgE to Ara h 2 if the clinician is considering a peanut OFC. We aimed to determine the OFC reduction in clinical practice as a result of this two-step diagnostic algorithm compared to using peanut SPT alone and perform a cost comparison between these two approaches. Methods: We performed an audit of all patients presenting to RCH allergy clinics undertaking assessment of peanut allergy. Adherence to the guideline, the number of OFCs required for diagnosis, and outcomes were determined. Modelled data of the same patient cohort estimated the number of OFCs that would have occurred if using peanut SPT alone. A cost comparison was performed, comparing these two approaches. Results: Eight thousand, eight hundred and twenty-six patients were included, with 9.2% proceeding to an OFC. Of these, 20.1% had a positive result (any allergic reaction), and anaphylaxis occurred in 1.1%. There was a reduction of 27.8% in OFCs when using the diagnostic algorithm compared to SPT alone. Using the diagnostic algorithm also resulted in a 32.05% cost reduction compared to the SPT-only pathway. Sensitivity analysis demonstrated the number of OFCs gives the greatest impact to the overall cost of diagnosis. Conclusions: A combined algorithm incorporating peanut SPT followed by sIgE to Ara h 2 resulted in a reduction in patients requiring OFCs and a cost saving in a clinical cohort.

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

Background: Skin lipids are crucial components of the skin barrier. Individuals with atopic dermatitis (AD or eczema) have a different skin lipid profile from those without. However, whether altered skin lipids precede and predict the subsequent risk of AD remained unclear, especially for different AD phenotypes. Objective: We sought to examine the relationship between skin lipids and subsequent AD and AD phenotypes in infants. Methods: Skin lipids from the forearms of 133 infants with family history of allergic disease were sampled using tape strips at age 6 weeks. Lipids were quantified using liquid chromatography-tandem mass spectrometry. AD by age 1 year was diagnosed using modified UK Working Party Criteria. Allergic sensitization was assessed using skin prick tests. Associations and predictive discrimination were estimated using univariable logistic regression. Potential causation was explored using multivariable logistic regression. Results: Reduced levels of 6 protein-bound ω-hydroxyl sphingosine (POS) ceramides with C30 and C32 fatty acids at 6 weeks were associated with increased risk of AD by age 1 year. In univariate models, a number of POS ceramides predicted subsequent AD, such as PO30:0-C20S (area under the curve, 0.65; 95% CI, 0.55-0.75). After confounders were adjusted, only PO30:0-C20S was associated with AD (adjusted odds ratio, 0.62; 95% CI, 0.39-0.96 per 1-SD increase), and a trend for AD without sensitization (adjusted odds ratio, 0.57; 95% CI, 0.31-1.05) but not AD with sensitization (adjusted odds ratio, 0.76; 95% CI, 0.39-1.47). Conclusions: Reduced levels of POS ceramides are associated with the development of nonatopic AD, suggesting that these lipids may play a role in the pathogenesis of AD and may be useful predictive biomarkers. Interventions that increase POS ceramides may reduce the incidence of AD.

Background: Few studies have examined the association between 24-hour movement behaviors and health in children in their first 2 years of primary school. This study aimed to examine how 24-hour movement behavior compositions at age 6 were related to body mass index (BMI), waist circumference, and internalizing and externalizing symptoms at ages 6 and 10. Methods: A subsample of 361 children from the HealthNuts cohort study with valid accelerometer data was included in the cross-sectional analysis. Of these, 279 had longitudinal data for social-emotional outcomes and 113 had longitudinal anthropometric data. Children's 24-hour movement behaviors (ie, sleep, sedentary time, light-intensity physical activity, and moderate- to vigorous-intensity physical activity [MVPA]) were assessed over 8 days using accelerometery and activity logs. BMI z score and waist circumference were assessed using standardized protocols, and parents reported on their child's internalizing and externalizing behaviors. Cross-sectional and longitudinal associations were estimated using compositional data analysis and compositional isotemporal substitution analysis. Results: Overall, 24-hour movement behaviors were significantly related to internalizing symptoms cross-sectionally and longitudinally and BMI z-score cross-sectionally. Results from compositional isotemporal substitution models indicated that replacing sedentary time or light-intensity physical activity with MVPA was associated with fewer internalizing symptoms at ages 6 and 10. Replacing time spent sedentary and in light-intensity physical activity or MVPA with sleep was associated with lower BMI z score at age 6. Conclusions: Spending more time in MVPA relative to other movement behaviors is associated with fewer internalizing symptoms. In additional, spending more time sleeping is associated with lower BMI z score and waist circumference in children.

Low Dose Multi-Nut Oral Immunotherapy in Pre-schoolers (LMNOP): a Pragmatic Randomised Controlled Trial of Low Dose Multi-Nut Oral Immunotherapy Versus Standard Care for the Treatment of Multi-Nut Allergies in Young Children