Association of obesity with IgE levels and allergy symptoms in children and adolescents: results from the National Health and Nutrition Examination Survey 2005-2006

Parents of 5-to-12-year-old children with food allergies report more frequent use of structure-based food parenting practices

Objectives

Food parenting practices (FPP) can have effects on children's eating behaviors. Over 8 million children in the US have food allergies, however, little is known about FPP for those who have children with food allergies. The objective of this study was to describe FPP among children with food allergies.

Methods

Recruited across the United States using ResearchMatch in February and March 2021, parents of children ages 5-12 years (n = 346; n = 77 with food allergies) completed a single, online survey which measured health history, demographics, and FPP. Linear regressions were used to examine associations between FPP of children with and without food allergies, and associations between food allergy factors and FPP.

Results

Parents of children with food allergies reported greater use of limit exposure than parents of children without food allergies (B = 0.131; [CI], 0.021-0.293; P = 0.024), with no differences in other types of FPP.

Conclusions

Parents of children with food allergies reported more frequent structure-based FPP than parents of children without food allergies. More work is needed to explore mechanisms that promote positive food parenting among this population.

Exploring the Complex Interplay of Obesity, Allergic Diseases, and Sleep-Disordered Breathing in Children

This narrative review study investigates the correlations between obesity, allergies, and sleep-disordered breathing in pediatric populations. Searches for pertinent articles were conducted on the Medline PubMed Advanced Search Builder, Scopus, and Web of Science databases from unlimited to April 2024. Sleep-disordered breathing causes repeated upper airway obstructions, leading to apneas and restless sleep. Childhood obesity, which affects around 20% of children, is often associated with sleep-disordered breathing and allergies such as asthma and allergic rhinitis. It is distinguished between diet-induced obesity (resulting from excess of diet and physical inactivity) and genetic obesity (such as is seen in Down syndrome and Prader-Willi syndrome). In children with diet-induced obesity, chronic inflammation linked to weight can worsen allergies and increase the risk and severity of asthma and rhinitis. Furthermore, the nasal congestion typical of rhinitis can contribute to upper respiratory tract obstruction and obstructive sleep apnea. A vicious circle is created between asthma and sleep-disordered breathing: uncontrolled asthma and sleep-disordered breathing can worsen each other. In children with genetic obesity, despite alterations in the immune system, fewer allergies are observed compared to the broader population. The causes of this reduced allergenicity are unclear but probably involve genetic, immunological, and environmental factors. Additional research is necessary to elucidate the underlying mechanisms. The present narrative review study emphasizes the importance of jointly evaluating and managing allergies, obesity, and obstructive sleep apnea in children considering their close interconnection.

National trends of allergic diseases and pandemic-related factors among individuals with obesity in South Korea: A nationwide representative serial study, 2005-2021

Background

Although obesity is known to be related to allergic diseases, few studies have investigated the prevalence of allergic diseases in individuals with obesity, especially during the COVID-19 pandemic. Thus, this study aimed to analyze national trends of allergic diseases among individuals with obesity and sociodemographic factors.

Methods

This study used data from the Korea National Health and Nutrition Examination Survey to examine the prevalence of allergic diseases among individuals with obesity in South Korea from 2005 to 2021. A nationally representative sample of 118,275 participants aged over 2 years or above was divided into six groups for analysis. This study used weighted multivariate regression analysis to examine the estimates of related factors. It assessed the weighted odds ratios or β-coefficients for these factors across different categories, including age, sex, region of residence, education level, household income, and body mass index for the entire population.

Results

All allergic diseases showed a general upward trend from 2005 to 2021, but each disease showed different prevalence trends when compared by age. Before the pandemic, those aged ≤39 years had an increasing trend for asthma and AD, but those aged ≥40 years had a decreasing trend. For asthma, β-coefficients were 0.629 (95 % CI, 0.299 to 0.958) for 19-39 years, -0.245 (-0.450 to -0.040) for 40-59 years, and -0.668 (-1.024 to -0.313) for ≥60 years. For AD, β-coefficients were 2.514 (1.258-3.769) in those aged 2-18 years, 0.630 (0.173-1.086) in those aged 19-39 years, -0.458 (-0.648 to -0.268) in those aged 40-59 years, and -0.253 (-0.454 to -0.052) in those aged ≥60 years. However, for both asthma and AD, there were no significant changes in prevalence during the pandemic. In the case of AR, trends were different from those of asthma and AD. Before the pandemic, AR showed an increasing trend in those aged ≤39 years and those aged ≥40 years: β-coefficients were 3.067 (2.344-3.790) in 19-39 years, 2.051 (1.609-2.493) in 40-59 years, and 1.173 (0.820-1.526) in ≥60 years. During the pandemic, there was an increasing trend only among those aged 40-59, with no significant changes in other age groups: β-coefficients were 1.438 (0.065-2.811) in 40-59 years.

Conclusions

From 2005 to 2021, all allergic diseases (asthma, AD, and AR) increased overall, but with different age-related trends. No significant link was found between COVID-19 and allergic diseases, possibly due to preventive measures like mask-wearing and social distancing. Anxiety about accessing healthcare during the pandemic likely contributed to a decline in allergy diagnoses, highlighting the need for comprehensive strategies to manage and prevent allergic diseases.

Cow's Milk Allergy May Induce Lipid Metabolism Disorder in BALB/c Mice via Exosomes

Allergic diseases and lipid-metabolism-disorder-derived diseases are both significant public health issues. Recent studies have shown that exosomes are associated with the course of allergic diseases and are involved in lipid metabolism. In this study, exosomes derived from cow's milk allergic (CMA) mice medially loaded lesser proteins favoring cholesterol metabolism. The levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-c) in the serum were increased in the CMA mice, and hepatic lipid deposition was observed in the liver, but these phenomena were improved by inhibiting the exosome release. Specifically, the higher expression of the sterol regulatory element binding factor 2 (SREBP2) protein and HMGCR gene in the liver of CMA mice indicated an increase in cholesterol synthesis. NPC1L1 was also highly expressed in the small intestine of CMA mice, and fecal TC level was decreased, suggesting that the reabsorption of cholesterol was elevated. The biosynthesis of cholesterol, the reverse cholesterol transport (RCT) process, and the synthesis of bile acid in the liver were improved by inhibiting exosome release, as well as the reabsorption of cholesterol in the small intestine. This study has for the first time demonstrated the lipid metabolism disorder caused by CMA, especially the important role of exosomes in food allergies and lipid metabolism.

Multi-omics analysis of Gwakhyangjeonggi-san for gastrointestinal complications in atopic dermatitis: A randomized, double-blinded, placebo-controlled, parallel-group clinical trial

ETHNOPHARMACOLOGICAL RELEVANCE

In traditional Chinese medicine (TCM) and traditional Korean medicine (TKM), Gwakhyangjeonggi-san (GJS) is an herbal decoction used to treat gastrointestinal disorders and allergic diseases. However, no randomized controlled trials have reported the efficacy and safety of GJS against atopic dermatitis (AD) or its comorbidities.

AIM OF THE STUDY

This clinical trial investigated the clinical efficacy and safety of GJS for treating patients with AD who have gastrointestinal symptoms, using a multi-omics approach that included 16S rRNA sequencing and metabolomics.

MATERIALS AND METHODS

This study was a randomized, double-blind, placebo-controlled, parallel-group clinical trial. Fifty-two patients with AD (age: 19-60) were randomly assigned to receive either the GJS (N = 27) or placebo (N = 25) granules thrice daily for 8 weeks. The primary outcome was measured as the change in the SCORing of Atopic Dermatitis index from baseline to 8 weeks. The secondary outcomes included the eczema area and severity index, dermatology life quality index, EuroQoL 5 dimensions 5 levels (EQ-5D-5L), immunological factors, gastrointestinal status, and safety evaluation. In addition, 16S rRNA sequencing on gut-microbiomes and non-targeted metabolomics approach using mass spectrometry on sera samples were applied to investigate the GJS therapeutic mechanism.

RESULTS

After 8 weeks, AD symptoms were reduced in both the GJS and placebo groups without any serious adverse events, but the reduction was not significantly different between the two groups. However, the EQ-5D-5L scores and gastrointestinal symptom scores, such as bitter-tasting fluid presenting in the mouth, upper abdomen bloating, and nausea, only improved in the GJS group. To further elucidate the effect of GJS on patients with AD who have gastrointestinal symptoms, 16S rRNA sequencing and metabolomics were executed. The GJS group had lower gut microbiome diversity including observed OUT, Ace, Chao1 and Shannon index than the placebo group at enrollment time, while the difference in gut microbiome diversity between GJS and placebo group was eliminated by 8 weeks of treatment. Consistently, the metabolomics results showed that the gut microbiome-derived uremic toxins, including indoxyl sulfate and phenylacetylglutamine, significantly increased in the placebo group, while these in GJS group were maintained without any significant change.

CONCLUSIONS

These results showed that the GJS had no significant effect on AD compared to the placebo but exerted a beneficial effect on improving the quality of life and gastrointestinal symptoms in patients with AD, and it acted by modulating gut microbiome diversity and gut microbiome-derived uremic toxins. Our findings support the use of GJS for AD comorbidities and also provide evidence that multi-omics approaches can be useful for understanding herbal decoctions in TCM and TKM comprehensively.

Early-life risk factors for food allergy: Dietary and environmental factors revisited

There appears a steep increase in the prevalence of food allergy worldwide in the past few decades. It is believed that, rather than genetic factors, the recently altered dietary and environmental factors are the driving forces behind the rapid increase of this disease. Accumulating evidence has implied that external exposures that occurred in prenatal and postnatal periods could affect the development of oral tolerance in later life. Understanding the potential risk factors for food allergy would greatly benefit the progress of intervention and therapy. In this review, we present updated knowledge on the dietary and environmental risk factors in early life that have been shown to impact the development of food allergy. These predominantly include dietary habits, microbial exposures, allergen exposure routes, environmental pollutants, and so on. The key evidence, conflicts, and potential research topics of each theory are discussed, and associated interventional strategies to prevent the disease development and ameliorate treatment burden are included. Accumulating evidence has supported the causative role of certain dietary and environmental factors in the establishment of oral tolerance in early life, especially the time of introducing allergenic foods, skin barrier function, and microbial exposures. In addition to certain immunomodulatory factors, increasing interest is raised toward modern dietary patterns, where adequately powered studies are required to identify contributions of those modifiable risk factors. This review broadens our understanding of the connections between diet, environment, and early-life immunity, thus benefiting the progress of intervention and therapy of food allergy.

Leptin favors imbalance of antigen-specific CD4+ T-cells associated with severity of cat allergy

Introduction

Obesity can complicate IgE-mediated allergic diseases. In the present study, we aimed to investigate the ability of obesity-related concentrations of leptin to modulate the in vitro effector and regulatory Fel d1-specific CD4+ T-cell subsets in patients allergic to cat, considered the third most common cause of respiratory allergy in humans.

Methods

For this study, plasma and peripheral blood mononuclear cells (PBMC) from 30 cat-allergic patients with mild, moderate and severe respiratory symptoms were obtained. The PBMC cultures were stimulated with Fel d1 antigen (10 µg/mL) in the presence or absence of obesity-related leptin dose (50 ηg/mL). After 6 days, the levels of cytokines and IgE in the supernatants were evaluated by multiplex and ELISA, respectively. The frequency of different non-follicular (CXCR5-) and follicular (CXCR5+) Fel d1-specific CD4+ T cell subsets was determined by flow cytometry. The plasma levels of leptin and IgE anti-cat titers were evaluated by ELISA and ImmunoCAP, respectively.

Results and conclusions

Fel d1 induced both IgE production and release of cytokines related to Th2, Th9 and Th17 cell phenotypes. Feld1 was more efficient in increasing the frequency of TFHIL-21- cells positive for IL-4, IL-5 and IL-13 than TFHIL-21+ cell subsets. Leptin favored the expansion Th2-like and Th9-like cells and TFHIL-21- cells positive for IL-4, IL-5 and IL-13, but reduced the proportion of conventional (Treg/Tr-1) and follicular (TFR) regulatory CD4+ T-cell subsets expressing or not CD39 marker. Finally, many of the imbalances between Fel d1-specific CD4+ T-cells were also correlated with plasma leptin and anti-Fel d1 IgE titers. In summary, hyperleptinemia should negatively impact on the severity of cat allergies by favoring the expansion of pathogenic Fel d1-specific CD4+ T-cell phenotypes and damaging the functional status of regulatory CD4+ T-cell subsets.

Chronic spontaneous urticaria and metabolic syndrome: a relationship conundrum

Chronic spontaneous urticaria (CSU) and metabolic syndrome (MetS) are associated with low-grade inflammation. Despite intensive research and various hypothesis, there is lack of specific pathomechanisms of urticaria. Previous studies have suggested low-grade inflammation in obesity which may be linked to urticaria. However, there is limited literature on association of MetS and CSU. So, this study was conducted to evaluate the association of MetS and its components in patients with CSU. This was a hospital-based and cross-sectional cohort study in which 481 patients of CSU and 240 age- and gender-matched controls were recruited. MetS was defined using the revised National Cholesterol Education Program Adult Treatment Panel III. BMI, waist circumference, blood pressure, fasting blood sugar, plasma insulin, and lipid profile were measured after overnight fasting. Pearson's Chi-squared test was used to calculate significance. Logistic regression analysis was done to assess MetS as a predictor of CSU. All patients were started on antihistamines according to the severity of the disease. CSU patients comprised 220 men (45.7%) and 261 women (54.3%) with 97 patients (20.12%) qualifying criteria for metabolic syndrome compared with 73 (30.42%) controls without any significant difference (p = 0.177). CSU was significantly associated with a higher prevalence of central obesity (p = 0.003) but CSU patients with central obesity did not have a higher urticaria activity score (p = 0.727) or serum IgE levels (p = 0.359). In conclusion, our study found an increased association of central obesity with CSU that was not related to the severity of urticaria. This is of significance as obesity is the most prevalent and first component of MetS to be developed. There was no increase in the overall prevalence of MetS in patients with CSU. The increased association of obesity and urticaria in our study can be partially explained by the role of antihistamines in modulation of metabolic pathway and appetite. Future research into the same can give better insights and thus can aid in better management options in CSU patients.

High excess-free-fructose beverage consumption is not associated with prevalent allergy in US adults: a population-based analysis of NHANES 2005-2006

BACKGROUND

A strong association exists between high-excess free fructose (EFF) beverage consumption and prevalent allergy in children and adolescents; however, whether this association exists in the adult population is unclear. Therefore, this study aimed to investigate the relationship between high-EFF beverage intake and prevalent allergy.

METHODS

This cross-sectional study extracted data from the National Health and Nutrition Examination Survey 2005-2006. Adults aged ≥ 20 were eligible for inclusion, excluding those without complete information on beverage intake, allergic symptom survey, and allergen-specific immunoglobulin E test results. A total of 2077 adults were included. Univariate and multivariable logistic regression analyses determined the associations between high-EFF beverage consumption, prevalent allergic symptoms, and allergic sensitization.

RESULTS

After adjusting for confounders, there were no significant associations between high intake (vs. low) of sum of high-EFF beverage (adjusted odds ratio [aOR] = 1.10, 95% confidence interval [CI] 0.77, 1.57), apple juice (aOR = 0.95, 95% 0.55, 1.65), fruit drinks (aOR = 0.95, 95%CI 0.70, 1.29), soft drinks (aOR = 1.17, 95%CI 0.89, 1.55) and presence of allergic sensitization, or allergic symptoms. Stratified analyses also revealed no associations between high intake of high-EFF beverage in sum, presence of allergic symptoms or sensitization among individuals aged 20-39y, 40-59y, and ≥ 60y.

CONCLUSIONS

Our findings indicate no independent association between frequent intake of high-EFF beverage and increased likelihood of allergy in US adults.

The Effect of Food Allergen Exclusion on the Growth of Saudi Children

With a variety of symptoms that can impede children's development, food allergies are an important public health concern. With the help of information from the King Fahad Medical City Hospital in Riyadh, we looked at how restricting certain foods affected the growth of Saudi children who had food allergies. An anonymous self-administered questionnaire asking about the individuals' demographics and their restricted eating habits was completed by 72 children (48 boys and 24 girls) between the ages of 2 and 14. The sensitivity of six allergens (hen eggs, cow milk, fish, wheat, peanuts, and soybeans), anthropometric indices, specific Immunoglobulin E (IgE) levels, and sensitivity were examined. The Statistical Package for Social Science (SPSS), version 26, was used to analyze the data. Chi-square and t-tests were used to examine the relationships between various category variables. According to the findings, most of the mothers of the children were between the ages of 30 and 40 (80.6%), had a college degree (72.3%), were unemployed (59.7%), and had a monthly family income between 5000 and 15,000 SAR (69.4%). Both sexes had specific IgE antibodies for allergens in classes 2 and 3, with boys having noticeably (p ≤ 0.05) higher quantities than girls. While females were more sensitive to fish and peanuts, boys were more likely than girls to show specific IgE sensitivity to egg white, cow milk, wheat, and soybeans. Both sexes' allergy levels were considerably (p ≤ 0.01) higher in children aged 5.01 to 10 than in other age groups. In terms of classifications of thinness, overweightness, and obesity, boys were slenderer than girls, and a greater percentage of boys than girls were overweight or obese. The exclusion of hen eggs, cow milk, wheat, and peanuts from the diet had a significant and detrimental effect on body mass index (BMI) and height-for-age ratio among children with impaired growth, in contrast to the demographic factors, which had a significant and favorable effect on the growth of other children. In conclusion, restrictions on food allergens impairs growth in Saudi children, particularly boys' growth.

Obesity-induced hyperglycemia impairs oral tolerance induction and aggravates food allergy

Obesity and type 2 diabetes (T2D) have been found to be associated with abnormalities in several organs, including the intestine. These conditions can lead to changes in gut homeostasis, compromising tolerance to luminal antigens and increasing susceptibility to food allergies. The underlying mechanisms for this phenomenon are not yet fully understood. In this study, we investigated changes in the intestinal mucosa of diet-induced obese mice and found that they exhibited increased gut permeability and reduced Treg cells frequency. Upon oral treatment with ovalbumin (OVA), obese mice failed to develop oral tolerance. However, hyperglycemia treatment improved intestinal permeability and oral tolerance induction in mice. Furthermore, we observed that obese mice exhibited a more severe food allergy to OVA, and this allergy was alleviated after treatment with a hypoglycemic drug. Importantly, our findings were translated to obese humans. Individuals with T2D had higher serum IgE levels and downregulated genes related to gut homeostasis. Taken together, our results suggest that obesity-induced hyperglycemia can lead to a failure in oral tolerance and to exacerbation of food allergy. These findings shed light on the mechanisms underlying the relationship among obesity, T2D, and gut mucosal immunity, which could inform the development of new therapeutic approaches.

Allergic Diseases and Childhood Obesity: A Detrimental Link?

Several epidemiological studies have described childhood obesity as a risk factor for atopic disease, particularly asthma. At the same time, this association seems to be more conflicting for allergic rhinitis, atopic dermatitis, and chronic urticaria. This article aims to deepen the possibility of a relationship between childhood obesity and allergic diseases. As regards asthma, the mechanical and inflammatory effects of obesity can lead to its development. In addition, excess adiposity is associated with increased production of inflammatory cytokines and adipokines, leading to low-grade systemic inflammation and an increased risk of asthma exacerbations. Allergic rhinitis, atopic dermatitis, food allergies, and chronic urticaria also seem to be related to this state of chronic low-grade systemic inflammation typical of obese children. Vitamin D deficiency appears to play a role in allergic rhinitis, while dyslipidemia and skin barrier defects could explain the link between obesity and atopic dermatitis. Starting from this evidence, it becomes of fundamental importance to act on body weight control to achieve general and allergic health, disentangling the detrimental link between obesity allergic diseases and childhood obesity. Further studies on the association between adiposity and atopy are needed, confirming the biologically active role of fat tissue in the development of allergic diseases and exploring the possibility of new therapeutic strategies.

Sugar-Sweetened Beverages and Allergy Traits at Second Year of Life: BRISA Cohort Study

Sugar-Sweetened Beverage (SSBs) consumption has risen in early life and it is plausible that it might increase children's risk of allergies. In this paper, we analyzed the association of SSB consumption with allergies in children's second year of life. This study analyzed data from a São Luís BRISA prenatal cohort in the follow-up of children (n = 1144) in their second year of life. Allergy Traits were a latent variable deduced from medical diagnoses of allergic rhinitis, atopic dermatitis, and food allergies. SSBs were investigated as a percentage of daily calories based on 24 h recalls, including industrialized fruit juices, soft drinks, and ready-made chocolate milk. Other variables analyzed were socioeconomic status, age, body mass index z-score, episodes of diarrhea, and breastfeeding. Our finds were that higher consumption of daily calories from SSBs was associated with higher Allergy Trait values (SC = 0.174; p = 0.025); older age (SC = -0.181; p = 0.030) was associated with lower Allergy Trait values; and episodes of diarrhea were correlated with Allergy Traits (SC = 0.287; p = 0.015). SSB exposure was associated with Allergy Traits in children's second year of life; thus, abstaining from these beverages may also confer additional advantages in curtailing allergic diseases during early childhood.

Association of prenatal obesity and cord blood cytokine levels with allergic diseases in children: A 10-year follow-up cohort study

Background and aim

Although studies have associated elevated prenatal obesity with increased risk of various diseases in offspring, little is known regarding the immune system. The aim of this study was to evaluate the relationship between prenatal obesity and levels of cytokines in umbilical cord blood and development of allergic disease during the first 10 years of life in an offspring.

Methods

A cohort of term infants born at the ShaoXing Women and Children Hospitals in China in 2011 was enrolled in this study. Flow cytometry was performed to measure levels of various cord blood cytokines, namely IL1β, IL2, IL10, IL6, IL8, IL17, IL12, TNF-α and IFN-γ. Next, logistic regression was used to explore the association of prenatal BMI with the development of allergic disease. The relationship between levels of each cord blood cytokine with prenatal BMI, and allergic disease development was tested using linear and logistic regression analyses, respectively.

Results

After 10 years of follow-up, higher prenatal BMI was significantly associated with development of allergic disease in children (HR = 2.45, 95% CI:1.08-5.57, P = 0.033). We also adjusted for maternal age, education and infant gender, and found that prenatal BMI was significantly associated with higher levels of IL12 (P = 0.023) and IL1β (P = 0.049) in cord blood. Moreover, we adjusted for maternal age, education, allergic dermatitis, gestation age and infant gender, and found that increase in each unit (1.26 pg/ml) in IL17 was associated with a 55.5% higher risk of allergic disease in 10-year-old children (HR = 1.55, 95%Cl: 0.99-2.45, P = 0.056). Meanwhile, after adjusting for maternal age, education level, gestation age, prenatal BMI, gestational weight gain, infant gender and birthweight, we found that for every unit increase in IL10, IL6 and IL1β, the risk of overweight/obesity in children after 10-year follow-up increased by 18.7% (HR = 1.19, 95%Cl: 1.01-1.40, P = 0.042), 13.9% (HR = 1.14, 95%Cl: 1.02-1.27, P = 0.021) and 41.3% (HR = 1.41, 95%Cl: 1.02-1.95, P = 0.036), respectively.

Conclusions

Prenatal obesity was positively correlated with allergic diseases in offspring. Cord blood cytokine may play mediating roles in the associations of prenatal obesity with offspring allergic diseases.

Obesity and the microbiome in atopic dermatitis: Therapeutic implications for PPAR-γ agonists

Atopic dermatitis (AD) is an inflammatory skin disease characterized by epidermal barrier disruption, Th2 immune responses to skin allergens and microbial dysbiosis within affected lesions. Studies within the past decade have revealed genetic and environmental factors contributing to AD in children. Obesity is a metabolic disorder that often manifests early in life and is associated with reduced bacterial diversity, leading to skin colonization with lipophilic bacteria and intestinal colonization with pro-inflammatory species. These changes impair epithelial barriers and promote Th17 responses, which may worsen the severity of AD symptoms. While few studies have examined the contribution of microbiota in obesity-induced allergies, there is emerging evidence that PPAR-γ may be an effective therapeutic target. This review discusses the microbiome in pediatric AD, treatment with probiotics, how disease is altered by obesity and potential therapeutic effects of PPAR-γ agonists. While healthy skin contains diverse species adapted for specific niches, lesional skin is highly colonized with Staphylococcus aureus which perpetuates the inflammatory reaction. Treatments for AD should help to restore microbial diversity in the skin and intestine, as well as epithelial barrier function. Pre-clinical models have shown that PPAR-γ agonists can suppress Th17 responses, IgE production and mast cell function, while improving the epidermal barrier and microbial homeostasis. Overall, PPAR-γ agonists may be effective in a subset of patients with AD, and future studies should distinguish their metabolic and anti-inflammatory effects in order to inform the best therapies.

25 Years of translational research in the Copenhagen Prospective Studies on Asthma in Childhood (COPSAC)

The Copenhagen Prospective Studies on Asthma in Childhood (COPSAC) mother-child cohorts have provided a foundation of 25 years of research on the origins, prevention, and natural history of childhood asthma and related disorders. COPSAC's approach is characterized by clinical translational research with longitudinal deep phenotyping and exposure assessments from pregnancy, in combination with multi-omic data layers and embedded randomized controlled trials. One trial showed that fish oil supplementation during pregnancy prevented childhood asthma and identified pregnant women with the highest benefits from supplementation, thereby creating the potential for personalized prevention. COPSAC revealed that airway colonization with pathogenic bacteria in early life is associated with an increased risk of asthma. Further, airway bacteria were shown to be a trigger of acute asthma-like symptoms, with benefit from antibiotic treatment. COPSAC identified an immature gut microbiome in early life as a risk factor for asthma and allergy and further demonstrated that asthma can be predicted by infant lung function. At a molecular level, COPSAC has identified novel susceptibility genes, early immune deviations, and metabolomic alterations associated with childhood asthma. Thus, the COPSAC research program has enhanced our understanding of the processes causing childhood asthma and has suggested means of personalized prevention and treatment.

Cytokines Profile and Lung Function in Children with Obesity and Asthma: A Case Control Study

The existence of common inflammatory biomarkers linking obesity and asthma in children has been hypothesized. Nevertheless, laboratory and clinical characteristics of children with obesity and asthma are still poorly defined. The primary aim of the present study is to investigate the lung function and the cytokine profile, in children with obesity and asthma. In this prospective, cross-sectional pilot study, pulmonary function tests, biochemical parameters, and serum cytokines levels were compared in three groups of 28 children each, matched for age and sex. Obese children showed normal forced spirometry values except an increased distal airway resistance in subjects with obesity and no asthma. Both groups including obese children showed higher leptin and IL-10 levels and lower adiponectin and TNF-alpha levels compared to children with no obesity and asthma. IL-33 and TGF-beta1 levels were higher in children with obesity and asthma vs. children with normal weight and asthma. Finally, IL-6 was undetectable in approximately 70% of obese children with no asthma, in 57% obese asthmatic children and in 100% of children with normal-weight and asthma. Children with obesity and asthma show the most striking cytokine profile, suggesting a pro-inflammatory role of fat mass in asthma development.

Factors of Obesity and Metabolically Healthy Obesity in Asia

The East Asian region (China, Japan, and South Korea) is comprised of almost 1.5 billion people and recent industrialization has brought with it a pandemic of rising obesity, even in children. As these countries are rapidly aging and functioning at sub-replacement birthrates, the burgeoning costs of obesity-related care may threaten socialized healthcare systems and quality of life. However, a condition called metabolically healthy obesity (MHO) has been found to be without immediate cardiopulmonary or diabetic risk. Thus, maintenance of the MHO condition for the obese in East Asia could buffer the burden of long-term obesity care on medical systems and knowledge of the biochemical, genetic, and physiological milieu associated with it could also provide new targets for intervention. Diverse physiological, psychological, environmental, and social factors play a role in obesogenesis and the transition of MHO to a metabolically unhealthy obesity. This review will give a broad survey of the various causes of obesity and MHO, with special emphasis on the East Asian population and studies from that region.

MicroRNA-regulated B cells in obesity

Obesity is a prevalent health risk by inducing chronic, low-grade inflammation and insulin resistance, in part from adipose tissue inflammation perpetuated by activated B cells and other resident immune cells. However, regulatory mechanisms controlling B-cell actions in adipose tissue remain poorly understood, limiting therapeutic innovations. MicroRNAs are potent regulators of immune cell dynamics through fine-tuning a network of downstream genes in multiple signaling pathways. In particular, miR-150 is crucial to B-cell development and suppresses obesity-associated inflammation via regulating adipose tissue B-cell function. Herein, we review the effect of microRNAs on B-cell development, activation, and function and highlight miR-150-regulated B-cell actions during obesity which modulate systemic inflammation and insulin resistance. In this way, we hope to promote translational discoveries that mitigate obesity-induced health risks by targeting microRNA-regulated B-cell actions.

Differential Effects of Obesity, Hyperlipidaemia, Dietary Intake and Physical Inactivity on Type I Versus Type IV Allergies

Background: Alongside metabolic diseases (esp. obesity), allergic disorders are becoming increasingly prevalent. Since both obesity and allergies are highly impacted by environmental determinants, with this study we assessed the potential link between metabolic implications and two distinct types of allergies. Methods: Using cross-sectional data from the German FoCus cohort, n = 385 allergy cases, either hay fever (=type I allergy, n = 183) or contact allergy (=type IV allergy, n = 202) were compared to age- and sex-matched healthy control subjects (1:1 ratio, in total n = 770) regarding their metabolic phenotype, diet, physical activity, sleep, gut microbial composition, and serum metabolite profile using suitable BMI-adjusted models. Results: Obesity and metabolic alterations were found significantly more prevalent in subjects with allergies. In fact, this relation was more pronounced in contact allergy than hay fever. Subsequent BMI-adjusted analysis reveals particular importance of co-occurring hyperlipidaemia for both allergy types. For contact allergy, we revealed a strong association to the dietary intake of poly-unsaturated fatty acids, particularly α-linolenic acid, as well as the enrichment of the corresponding metabolic pathway. For hay fever, there were no major associations to the diet but to a lower physical activity level, shorter duration of sleep, and an altered gut microbial composition. Finally, genetic predisposition for hyperlipidaemia was associated to both contact allergy and hay fever. Conclusions: Reflected by higher allergy prevalence, our findings indicate an impaired immune response in obesity and hyperlipidaemia, which is differentially regulated in type I and type IV allergies by an unfavourable lifestyle constellation and subsequent microbial and metabolic dysfunctions.

Leptin, Obesity Parameters, and Atopy Among Children with Asthma

Leptin, as a major adipokine, positively correlates with the body's fat, while atopy is an important feature in the development of childhood asthma. We aimed to evaluate the relationship between leptin, parameters of obesity, and atopy in children with asthma. The study included 112 children (73 boys, 39 girls, mean age 11.1±2.4). 41 were overweight, 38 had asthma and a normal body mass index (BMI), and 33 were overweight asthmatics. Serum leptin levels, BMI, waist circumference (WC), and waist to hips ratio (WHR) were measured. Skin prick test (SPT)/CAP, total serum IgE, fractional exhaled nitric oxide (FeNO), and pulmonary function tests were performed. In asthmatic children, serum leptin median level was 9.2±16.2 ng/ml, in overweight children was 30.6±21.6 ng/ml, and in overweight asthmatics was 31.1±20.3 ng/ml with a significant difference between the groups (p=0.0374), yet with a significantly lower median level in the group of children with asthma compared to the overweight children: with asthma (p=0.00001) and without asthma (p=0.00001). In the three groups of patients, BMI and WC displayed a significant positive correlation with leptin (for BMI r=0.652 vs. r=0.530 vs. r=0.563, respectively and for WC r=0.508 vs. r=0.426 vs. r=0.527, respectively). No significant correlations of leptin within atopy parameters (Eo, IgE, SPT/CAP, FeNO) in all three analyzed groups (p>0.05) was detected. Conclusion: Atopy was not confirmed as an underlying mechanism of the association between asthma and being overweight. Leptin had a significant linear correlation as a parameter of central obesity with BMI and WC in all three groups, but not with WHR.

Prevalence, Risk Factors, Clinical Manifestation, Diagnosis Aspects and Nutrition Therapy in Relation to both IgE and IgG Cow’s Milk Protein Allergies among a Population of Saudi Arabia: A Literature Review

Cow milk protein allergy (CMPA) becoming a major public health issue that has attracted the attention of health professionals and researchers. This paper aimed to review the important aspects of both IgE and IgG types of cow’s milk protein allergy in terms of prevalence, clinical manifestation, risk factors, other health-related issues and nutritional therapy proposed for such allergies in the adult and pediatric population in Saudi Arabia. A search on “cow’s milk allergy” was done using PubMed, Google Scholar and Scopus Engine for published papers between 1993 and 2020 to find studies yielding knowledge on that context. The prevalence of cow’s milk protein allergy (CMPA) among infants is now in the range of 2–3%. This type of allergy is also detected in adulthood but less frequently. CMPA is defined as an immunological reaction to specific proteins in milk. CMPA is classified based on its type as an immunoglobulin E (IgE)-mediated form and an immunoglobulin G (IgG)-mediated form, each type representing different immunological pathways. The presence of Genetic aspects, family history and short duration of breastfeeding in the infant are among the risk factors contributing to this form of allergy. Its manifestations mainly present as skin presentation, followed by the gastrointestinal and respiratory presentation in most cases in addition to a life-threatening anaphylactic reaction that may occur in 12% of cases. food allergy committees have developed strict diagnosis criteria, including blood testing for food-specific immunoglobulin E (sIgE), a skin prick test and double-blind placebo-controlled food challenges (DBPCFC) as the gold standard. A diet free of cow’s milk protein (CMP) allergen and including the appropriate alternative milk formula is the first line of prevention recommended by many organizations and food allergy experts. As for Saudi Arabia, more research and clinical trials are required to discuss the various aspects of adult and pediatric CMPA and to provide a better understanding along with good control strategies implementation.

Obesity, a major risk factor for immunity and severe outcomes of COVID-19

An influenza-like virus named severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for COVID-19 disease and spread worldwide within a short time. COVID-19 has now become a significant concern for public health. Obesity is highly prevalent worldwide and is considered a risk factor for impairing the adaptive immune system. Although diabetes, hypertension, cardiovascular disease (CVD), and renal failure are considered the risk factors for COVID-19, obesity is not yet well-considered. The present study approaches establishing a systemic association between the prevalence of obesity and its impact on immunity concerning the severe outcomes of COVID-19 utilizing existing knowledge. Overall study outcomes documented the worldwide prevalence of obesity, its effects on immunity, and a possible underlying mechanism covering obesity-related risk pathways for the severe outcomes of COVID-19. Overall understanding from the present study is that being an immune system impairing factor, the role of obesity in the severe outcomes of COVID-19 is worthy.

Is Body Mass Index Related to Skin Reactivity to Histamine but not to Specific Allergens? A 2-Year Follow-up Study on Korean Children

BACKGROUND

Skin prick tests are widely used to diagnose allergic sensitization. The influence of obesity on the skin prick test result has not been clearly established, even though the association between allergic disease and obesity is relatively well known.

OBJECTIVE

To determine whether a change in body mass index (BMI) contributes to skin reactivity to histamine and allergens in a skin prick test, we performed a 2-year follow-up study on Korean children.

METHODS

Skin prick tests for common aeroallergens were performed on elementary school students from Jeju Island, Korea. BMI was calculated using weight and height after measuring both, and demographic characteristics were surveyed. The same tests were repeated after 2 years.

RESULTS

The sensitization rate increased during the 2 years between tests and the children's mean BMI also increased, along with their age. The wheal sizes induced by Dermatophagoides pteronyssinus, Dermatophagoides farinae, Japanese cedar, and histamine were significantly increased during 2 years; however, only the histamine reaction associated with increased BMI had statistical significance. Furthermore, other variables-including the number of sensitized allergens-were not related to histamine skin reactivity.

CONCLUSION

Histamine skin reactivity increased in children over time and some allergens showed increased specific reactions; however, BMI gain is a specific predictor of histamine reactivity. Further studies are needed to elucidate the clinical significance of these changes.

Primary Prevention of Food Allergy-Environmental Protection beyond Diet

A food allergy is a potentially life-threatening disease with a genetic and environmental background. As its prevalence has increased significantly in recent years, the need for its effective prevention has been emphasized. The role of diet modifications and nutrients in food allergy reduction has been extensively studied. Much less is known about the role of other environmental factors, which can influence the incidence of this disease. Changes in neonates gut microbiome by delivery mode, animal contact, inhalant allergens, oral and then cutaneous allergen exposure, air pollution, smoking, infections and vaccinations can be the potential modifiers of food allergy development. There is some data about their role as the risk or preventive factors, but yet the results are not entirely consistent. In this paper we present the current knowledge about their possible role in primary prevention of food allergies. We discuss the mechanisms of action, difficulties in designing accurate studies about food allergy and the potential biases in interpreting the connection between environmental factors and food allergy prevention. A better understanding of the role of environmental factors in food allergies development may help in implementing practical solutions for food allergy primary prevention in the future.

The association between overweight and prevalence of food allergy in Japanese children: a cross-sectional study

Background

Food allergy (FA) is a common disease in children, and its prevalence has increased in developed countries. The impact of overweight on children health also becomes an important social problem. However, the relationship between overweight and FA is still unclear. We examined the association between overweight and the prevalence of FA among Japanese children.

Methods

We analyzed data obtained using a self-administered questionnaire from 1772 Japanese children. Weight groups according to body mass index cutoff points proposed by the International Obesity Task Force were used to create two groups: overweight and non-overweight. Children were separated into four age groups (3–6 years, 6–9 years, 9–12 years, and 12–15 years) to examine age differences. We performed univariate and multivariate logistic models to examine the association between overweight and FA.

Results

The prevalence of FA was significantly higher in boys (10.6%, p = 0.014) than girls (4.5%) and girls (7.9%, p = 0.012) than boys (2.5%) for 6–9 and 12–15 age groups, respectively. While the prevalence of FA was significantly higher in overweight than non-overweight girls (26.1%, p = 0.005) in the 12–15 age group, no significant difference was found in boys. In girls, overweight was significantly associated with FA after adjustment for age and asthma (odds ratio 1.99, 95% confidence interval 1.01–3.89, p = 0.046).

Conclusions

Our results showed that being overweight was significantly associated with a higher prevalence of FA in girls, but not in boys. Further prospective studies are necessary to find the causal relationship between overweight and FA.

The impact of obesity on immune function in pediatric asthma

PURPOSE OF REVIEW

Pediatric obese asthma is a complex disease that remains poorly understood. The increasing worldwide incidence of both asthma and obesity over the last few decades, their current high prevalence and the challenges in treating obese asthmatic patients all highlight the importance of a better understanding of the pathophysiological mechanisms in obese asthma. While it is well established that patients with obesity are at an increased risk of developing asthma, the mechanisms by which obesity drives the onset of asthma, and modifies existing asthma, remain unclear. Here, we will focus on mechanisms by which obesity alters immune function in asthma.

RECENT FINDINGS

Lung parenchyma has an altered structure in some pediatric obese asthmatics, known as dysanapsis. Central adiposity is linked to reduced pulmonary function and a better predictor of asthma risk in children than BMI. Obesity in young children is associated with an increased risk of developing asthma, as well as early puberty, and hormonal alterations are implicated in obese asthma. Obesity and asthma each yield immunometabolic dysregulation separately and we are learning more about alterations in these pathways in pediatric obese asthma and the potential impact of bariatric surgery on those processes.

SUMMARY

The recent progress in clarifying the connections between childhood obesity and asthma and their combined impacts on immune function moves us closer to the goals of improved understanding of the pathophysiological mechanisms underpinning obese asthma and improved therapeutic target selection. However, this common inflammatory disease remains understudied, especially in children, and much remains to be learned.

Insulin Resistance Increases Serum Immunoglobulin E Sensitization in Premenopausal Women

Background

Although studies have shown that obesity is associated with aeroallergen sensitization (atopy), controversy still exists. We aimed to investigate the association between metabolic status, obesity, and atopy stratified by sex and menopausal status.

Methods

A total of 1,700 adults from the 2010 Korean National Health and Nutrition Examination Survey were classified into metabolically healthy nonobese (MHNO), metabolically unhealthy nonobese (MUNO), metabolically healthy obese (MHO), and metabolically unhealthy obese (MUO) by body mass index and insulin resistance. Atopy was defined as a positive response to at least one aeroallergen. Multiple regression analysis was used to evaluate the risk of immunoglobulin E (IgE) elevation or atopy in relation to the degree of metabolic abnormality and obesity.

Results

In premenopausal women, total IgE was positively correlated with obesity and insulin resistance. MUNO participants had a higher risk of having elevated total IgE compared to MHNO participants (odds ratio [OR], 2.271; 95% confidence interval [CI], 1.201 to 4.294), while MHO participants did not show a significant difference (OR, 1.435; 95% CI, 0.656 to 3.137) in premenopausal women. MUNO, but not MHO was also associated with atopy (OR, 2.157; 95% CI, 1.284 to 3.625). In men and postmenopausal women, there was no significant difference between metabolic status, obesity, and atopy among groups.

Conclusion

Increased insulin resistance is associated with total IgE and atopy in premenopausal women but not in postmenopausal women or men.

The relationship between malnutrition and TH 2 immune markers: a study in school-aged children of different socio-economic backgrounds in Makassar, Indonesia

OBJECTIVE

The burden of underweight remains a major problem in Indonesia, and at the same time, the prevalence of overweight is increasing. Malnutrition is a major determinant of health and has been linked to allergic disorders in children. We examined the relationship between malnutrition and TH 2 immune markers in school-aged children in Makassar, Indonesia.

METHODS

A cross-sectional study was performed in five schools where socio-demographic characteristics were recorded. Children's standardised z-scores of body mass index (z-BMI) and age-standardised z-scores of height (z-HA) were assessed using WHO child growth standards. Skin prick test (SPT) reactivity was determined to house dust mite allergens. Helminth infection status, (growth) hormones including insulin-like growth factor (IGF-1) and TH 2 immune markers were measured.

RESULTS

In total, 954 children were included of whom 21.6% were underweight and 14.8% overweight. After controlling for confounders, overweight was positively associated with leptin (GMR 3.55, 95% CI: 2.99-4.23) and IGF-1 (GMR 1.45, 95% CI: 1.15-1.82), whereas underweight was negatively associated (respectively GMR 0.57, 95% CI: 0.49-0.66 and GMR 0.78, 95% CI: 0.63-0.97). Underweight was associated with a lower eosinophil count (GMR 0.79, 95% CI: 0.64-0.97) but not with total IgE levels or SPT reactivity. Overweight was positively associated with SPT reactivity (adjusted OR 2.68, 95% CI: 1.50-4.78) but no relationship was found with the other TH 2 immune markers.

CONCLUSION

Malnutrition is prominent in school-aged children in Makassar, with overweight associated with increased SPT reactivity. Therefore, interventions should focus on undernutrition, but also on overweight to prevent the increase of allergic disorders in Indonesia.

Assessing the effect of prolonged use of desloratadine on adipose Brillouin shift and composition in rats

Antihistamines, which are commonly used to treat allergic reactions, are known for their side effects, which contribute to weight gain. It is hypothesized that simultaneous Brillouin elastography and Raman spectroscopy can be used to detect changes in adipose tissue associated with a prolonged intake of desloratadine, a commonly used second generation antihistamine. White and brown adipose tissue samples were excised from adult rats following 16 weeks of daily administration of desloratadine. It was found that the prolonged intake of desloratadine leads to an increase in Brillouin shift in both adipose tissue types. Raman spectra indicate that antihistamine use reduces protein-to-lipid ratio in brown adipose tissue but not white adipose tissue, indicating the effect on adipose tissue is location-dependent.

Investigation of Serum Total IgE and Eosinophil Levels in Different Allergic Diseases Together with the Study of Their Correlations with Various Possible Allergens in Mosul City

Serum total IgE (tIgE) is frequently used in the diagnosis of allergic diseases in Mosul city and Iraq. However, neither normal nor elevated levels can exclude or confirm the diagnosis of these diseases. Here, we tried to evaluate the validity of tIgE in the diagnosis of allergic asthma(AS), allergic rhinitis(AR) and atopic dermatitis(AD) in a sample of Mosul population, to set up an optimum cut-off value for diagnosis of these diseases and to study its correlation with different parameters that might affect its level. 38 patients with AS, 27 with AR, 46 with AD and 45 healthy controls were included in this study. tIgE were determined by ELISA and compared between allergic diseases and controls. Blood eosinophilia was ascertained and correlated with tIgE levels. The geometric means of tIgE were 316.87 IU/ml (95% CI: 234.69 to 427.82) in AS, 262.07 IU/ml (95% CI:174.24 to 394.18) in AR and 270.48 IU/ml (95% CI:202.57 to 361.16) in AD compared to 16.90 IU/ml (95% CI:12.32 to 23.18) in healthy controls. tIgE in allergic diseases was significantly increased in comparison to healthy controls (P <.0001). Female gender influenced tIgE in AS, but not in AR or AD. tIgE predominated in younger age groups; however, no significant difference was found between younger and older groups. Optimum values for tIgE with best discriminative accuracy were 77 IU/ml for AS and 81 IU/ml for AR and AD. Eosinophils count appeared to be a useful adjunct, and correlate well with tIgE in the diagnosis of allergic diseases.

Factors Influencing Total Serum IgE in Adults: The Role of Obesity and Related Metabolic Disorders

BACKGROUND AND AIM

Few reports have investigated the association between metabolic abnormalities (obesity and related metabolic syndrome) and total serum IgE concentrations.

METHODS

This cross-sectional study included a random sample of 1,516 adult individuals (44.7% men, aged 18-91 years, median 52 years) from a single municipality in Spain. Serum IgE was measured in the ADVIA Centaur system. Atopy was defined by the presence of positive skin prick tests to a panel of common aeroallergens in the area. Body mass index and data related to the definition of metabolic syndrome were obtained from all participants. Alcohol consumption, smoking, and regular physical exercise were assessed by a questionnaire.

RESULTS

Atopy (present in 21.9% of 1,514 evaluable individuals) was the strongest factor determining serum IgE concentrations. Male sex and heavy alcohol drinking were independently associated with higher IgE concentrations, particularly in the non-atopic individuals. Body mass index was positively associated with IgE concentrations, independent of potential confounders, although the effect was only evident among non-atopic individuals. In that group, median IgE concentrations in normal-weight and obese individuals were 15 and 24 kU/L, respectively (p < 0.001); likewise, obesity was associated with high (>100 kU/L) IgE concentrations after adjusting for potential confounders (odds ratio: 1.79, 95% confidence interval: 1.26-2.56, p = 0.001). The presence of metabolic syndrome and its components, particularly abdominal obesity and hyperglycaemia, was also positively and independently associated with higher IgE concentrations in non-atopic individuals.

CONCLUSIONS

Obesity and metabolic syndrome components are associated with high total serum IgE concentrations, particularly in non-atopic individuals.

Soluble pattern recognition molecules: Guardians and regulators of homeostasis at airway mucosal surfaces

Maintenance of homeostasis at body barriers that are constantly challenged by microbes, toxins and potentially bioactive (macro)molecules requires complex, highly orchestrated mechanisms of protection. Recent discoveries in respiratory research have shed light on the unprecedented role of airway epithelial cells (AEC), which, besides immune cells homing to the lung, also significantly contribute to host defence by expressing membrane‐bound and soluble pattern recognition receptors (sPRR). Recent evidence suggests that distinct, evolutionary ancient, sPRR secreted by AEC might become activated by usually innocuous proteins, commonly referred to as allergens. We here provide a systematic overview on sPRR detectable in the mucus lining of AEC. Some of them become actively produced and secreted by AECs (like the pentraxins C‐reactive protein and pentraxin 3; the collectins mannose binding protein and surfactant proteins A and D; H‐ficolin; serum amyloid A; and the complement components C3 and C5). Others are elaborated by innate and adaptive immune cells such as monocytes/macrophages and T cells (like the pentraxins C‐reactive protein and pentraxin 3; L‐ficolin; serum amyloid A; and the complement components C3 and C5). Herein we discuss how sPRRs may contribute to homeostasis but sometimes also to overt disease (e.g. airway hyperreactivity and asthma) at the alveolar–air interface.

Trick or treat? - when children with childhood food allergies lead parents into unhealthy food choices

BACKGROUND

This study examines the relationships between childhood food allergy and parental unhealthy food choices for their children across attitudes towards childhood obesity as mediators and parental gender, income and education as potential moderators.

METHODS

We surveyed parents with at least one child between the ages of 6 and 12 living in Canada and the United States. We received 483 valid responses that were analysed using structural equation modelling approach with bootstrapping to test the hypothetical path model and its invariance across the moderators.

RESULTS

The analysis revealed that pressure to eat fully mediated the effects of childhood food allergy and restriction on parental unhealthy food choices for their children. Finally, we found that parental gender moderated the relationship between childhood food allergy and the pressure to eat.

CONCLUSIONS

The paper contributes to the literature on food allergies among children and the marginalisation of families with allergies. Our explorative model is a first of its kind and offers a fresh perspective on complex relationships between variables under consideration. Although our data collection took place prior to Covid-19 outbreak, this paper bears yet particular significance as it casts light on how families with allergies should be part of the priority groups to have access to food supply during crisis periods.

Asthma and Obesity in Children

Asthma and obesity are two major chronic diseases in children and adolescents. Recent scientific evidence points out a causative role of obesity in asthma predisposition. However, studies assessing the real impact of excessive weight gain on lung function in children have shown heterogeneous results. In this review, the pathological mechanisms linking obesity and development of asthma in children are summarized and factors influencing this relationship are evaluated. Common disease modifying factors including age, sex, ethnicity, development of atopic conditions, and metabolic alterations significantly affect the onset and phenotypic characteristics of asthma. Given this, the impact of these several factors on the obesity–asthma link were considered, and from revision of the literature we suggest the possibility to define three main clinical subtypes on the basis of epidemiological data and physiological–molecular pathways: obese-asthmatic and atopy, obese-asthmatic and insulin-resistance, and obese-asthmatic and dyslipidemia. The hypothesis of the different clinical subtypes characterizing a unique phenotype might have an important impact for both future clinical management and research priorities. This might imply the necessity to study the obese asthmatic child with a “multidisciplinary approach”, evaluating the endocrinological and pneumological aspects simultaneously. This different approach might also make it possible to intervene earlier in a specific manner, possibly with a personalized and tailored treatment. Surely this hypothesis needs longitudinal and well-conducted future studies to be validated.

Gender aspects in food allergy

PURPOSE OF REVIEW

The difference of food allergy prevalence between male and female individuals is well documented and should have more impact for personalized diagnosis and management. Although in younger age male sex dominates, in adults more women are affected by food allergies. This sex disparity diminishes again around menopause, underlining the influence of sex hormones, but in addition, also metabolic gender-specific factors and differences in microbiome composition might contribute to the different expression of food allergy in the two genders. The sex-dependent and gender-dependent influence on development of food allergy, disease severity, as well as on social, dietary and neuropsychological factors in studies mainly published within past 18 months are discussed in this review.

RECENT FINDINGS

Sex and gender differences likely play a role in food allergy development, for instance via influence on immune cells and mediators, or on the composition of the microbiome, but only few controlled studies on this specific topic are available.

SUMMARY

Future prospective studies need to clearly take into account the sex and gender difference in order to provide personalized diagnosis, management and treatment of food allergy.

Usefulness of routine blood test-driven clusters for predicting acute exacerbation in patients with asthma

AIM

Acute exacerbation (AE) is a significant burden in the management of asthma. In this study we aimed to investigate whether routine blood test results predicted AE in asthmatics.

METHODS

We applied k-means cluster to routine blood test results which included eosinophil counts, total calcium, phosphorus, uric acid (UA), total cholesterol, total protein, albumin, total bilirubin, alkaline phosphatase, aspartate transaminase (AST), alanine transferase (ALT), gamma-glutamyltransferase, blood urea nitrogen, creatinine, and high-sensitive C-reactive protein (hsCRP) obtained from 590 asthmatics. AEs collected over the prospective follow-up of one-year were used to evaluate clinical trajectories of these clusters.

RESULTS

Three blood clusters were identified. The essential features of each cluster can be characterized as follows: (i) high eosinophil count, UA, total cholesterol, AST, ALT, and hsCRP levels (Cluster 1); (ii) intermediate features (Cluster 2); (iii) low UA, total cholesterol and total bilirubin levels (Cluster 3). Kaplan-Meier analysis confirmed that clusters were strongly predictive of time to the first AE (log-rank P = 0.001). Hazard ratio for each group was as follows: Cluster 2 = 1, Cluster 1 = 2.67 (1 vs. 2, P = 4.68 × 10^-4), and Cluster 3 = 1.69 (2 vs. 3, P = 0.021).

CONCLUSIONS

We defined three blood clusters in asthmatics. These blood clusters are easily identifiable from routine test results and may help clinicians to predict the future risk of AE in asthmatics.

Pro-inflammatory immunological effects of adipose tissue and risk of food allergy in obesity: Focus on immunological mechanisms

Over the past three decades, the number of obese people has risen steadily. The chronic low-grade inflammatory state and the non-specific activation of the immune system have contributed greatly to the development of obesity-related immunology. Food allergy as a kind of inflammatory disease with abnormal immune response may be associated with obesity. This review begins with the pro-inflammatory immunological effects of adipose tissue in obesity, and explains the possible effects of obesity on food allergy. In short, obesity not only directly causes imbalance of allergic-related immune cells in adipose tissue, but also indirectly causes this consequence through affecting expression of adipocytokines and peroxisome proliferator-activated receptor gamma (PPARγ) in adipose tissue. As a result, circulating levels of pro-inflammatory factors which are partly derived from adipose tissue increase, which might cause intestinal barrier injury. Therefore, obesity may increase the risk of food allergy.

Taeumjowi-tang, a Traditional Korean Sasang Remedy, Improves Obesity-Atopic Dermatitis Comorbidity by Regulating Hypoxia-Inducible Factor 1 Alpha

Atopic dermatitis (AD) is an inflammatory disease of the skin, resulting from an immune dysfunction, that often occurs as a comorbidity of obesity. This investigation evaluated the capacity of Taeumjowi-tang (TJT), a Korean herbal formulation from the Sasang medical tradition to influence prognostic features of AD and obesity in a mouse model. Here, obesity and AD were induced by a high-fat diet (HFD) and 1-fluoro-2,4-dinitrobenzene (DNFB). Following an 8-week HFD regimen and 4 weeks of DNFB administration, the comorbid (CO) group manifested increased body weight and AD-like lesions, as compared to normal control (NC) mice, while TJT administration diminished these symptoms of obesity and AD. Specifically, TJT treatment reduced epidermal thickness and eosinophil/mast cell infiltration, along with reduction in immunoglobulin E, interleukin (IL)-4, IL-6, and tumor necrosis factor-alpha (TNF-α). It was additionally demonstrated that TJT suppresses HFD/DNFB-associated increase of the inflammation-related nuclear factor-kappa beta (NF-κB) and mitogen activated protein kinase. Moreover, significantly increased levels of hypoxia inducible factor-1 alpha (HIF-1α) protein was observed in CO group versus controls, an increase significantly down-regulated by TJT-treatment. These outcomes suggest that TJT may prove useful in clinical management of obesity-AD comorbidity treatment, an effect that may be due to regulation of HIF-1α expression.

Microbial interactions in the atopic march

The human body is populated by a large number of microorganisms and exist in symbiosis with these immensely diverse communities, which are suggested to influence health and disease. The microbiota plays an essential role in the maturation and function of the immune system. The prevalence of atopic diseases has increased drastically over the past decades, and the co-occurrence of multiple allergic diseases and allergic sensitization starting in early life has gained a great deal of attention. Immune responses in different organs affected by allergic diseases (e.g. skin, intestine and lung) may be linked to microbial changes in peripheral tissues. In the current review, we provide an overview of the current understanding of microbial interactions in allergic diseases and their potential role in the atopic march.

The potential anti-inflammatory role of adiponectin in food allergy: a case-control study on children

We aimed to assess the possible relationship between food allergy and two key adipokines - leptin and adiponectin - in children with food allergy. A total of forty patients with definite diagnosis of food allergy according to clinical history and specific IgE (sIgE) for food allergens (group I) were enrolled in this pilot study. The control group (group II) included thirty children with no evidence of allergic symptoms. Serum levels of leptin and adiponectin were measured by ELISA. Meanwhile, sIgE was measured for the eight most common food allergens by the immunoblot method in all participants. The median ages in groups I and II were 18·5 and 23·5 months, respectively. The respective Caesarean section rate was 64·9 and 16·7 % in groups I and II (P<0·001). Serum levels of adiponectin were significantly higher in the patient group compared with controls (24·11 (sd 12·14) v. 10·67 (sd 12·23) μg/ml, P<0·001), whereas no statistically meaningful difference was detected in serum leptin concentrations (P=0·92). There was a significant inverse relationship between age and adiponectin levels in group I (P=0·002, r -0·479) and group II (P=0·04, r -0·365), and it was more significant in group I. The most common allergens in the patient group were wheat (52·5 %), hazelnut (52·5 %), cow's milk (50 %) and egg white (30 %). The results of this study suggest an essential link between adiponectin and food allergy that is probably unlikely to be affected by obesity as a confounding factor.

The Relationship Between Body Mass Index in Children and Insurance Type, Parental Eating Concern, Asthma, and Allergies

INTRODUCTION

Trust for America's Health reported rising levels of obesity contributed to increased disease rates and health care costs (Levi et al., 2013). Factors associated with overweight and obesity rates include lower socioeconomic status, public insurance, and increased chronic disease rates.

METHODS

Body mass index percentile, health insurance, parental eating concern, asthma, and allergy information were evaluated from a dataset of 870 de-identified health assessment records.

RESULTS

Among overweight/obese children, we found significant differences in children insured by Medicaid (26%) versus commercial insurance (15.9%), children with asthma (22.1%) versus children without asthma (14.8%), and children with known allergies (7.8%) versus children without known allergies (16.7%). The difference between children with parental eating concerns (3.7%) and children without (18.1%) was nearly significant.

DISCUSSION

The associations depicted can assist pediatric providers in recognizing risk factors for overweight/obesity among their patients. Combating obesity in childhood can improve health outcomes.

Role of dietary lipids in food allergy

The prevalence of food allergy is raising in industrialized countries, but the mechanisms behind this increased incidence are not fully understood. Environmental factors are believed to play a role in allergic diseases, including lifestyle influences, such as diet. There is a close relationship between allergens and lipids, with many allergenic proteins having the ability to bind lipids. Dietary lipids exert pro-inflammatory or anti-inflammatory functions on cells of the innate immunity and influence antigen presentation to cells of the adaptive immunity. In addition to modifying the immunostimulating properties of proteins, lipids also alter their digestibility and intestinal absorption, changing allergen bioavailability. This study provides an overview of the role of dietary lipids in food allergy, taking into account epidemiological information, as well as results of mechanistic investigations using in vivo, ex vivo and in vitro models. The emerging link among high-fat diets, obesity, and allergy is also discussed.

High-Sensitivity C-Reactive Protein and Allergic Endpoints in German Adolescents

BACKGROUND

Assessing high-sensitivity C-reactive protein (hs-CRP) in relation to allergic endpoints can shed light on both the mechanisms of allergic disease development and early non-communicable disease prevention. However, only a few epidemiological studies so far have investigated the relationship in children and adolescents, and the results were mixed.

OBJECTIVES

We sought to examine the interrelation between hs-CRP levels and allergic outcomes using a larger population size and a longitudinal study design.

METHODS

Complete data were available on 1,955 participants from the 15-years follow-up of the 2 large population-based German birth cohorts - GINIplus and LISA. Serum hs-CRP concentrations were measured using the immunoturbidimetric high-sensitive assay. Six allergic endpoints were used - doctor-diagnosed asthma, doctor-diagnosed eczema, doctor-diagnosed allergic rhinitis, food sensitization, aeroallergen sensitization, and any sensitization. We used generalized estimation equation models to assess the associations between hs-CRP levels and allergic endpoints.

RESULTS

Our longitudinal analyses did not detect any significant association between hs-CRP levels and any of the studied allergic outcomes (e.g., asthma, eczema, allergic rhinitis, food sensitization, aeroallergen sensitization, and any sensitization). The results were consistent in a series of sensitivity analyses.

CONCLUSIONS

Our study suggests that there is no association between hs-CRP levels and any of the allergic endpoints in German adolescents. However, whether allergic diseases are inflammatory conditions and which markers might be most sensitive, remain to be confirmed in future studies.

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.

Pediatric Obesity and the Immune System

Obesity has reached pandemic proportion and represents a major risk for several comorbidities. In addition to metabolic and cardiovascular obesity-related diseases, recent evidence suggested that obesity might affect immune system function. Adipose tissue is considered an endocrine organ that actively secretes cytokines also referred to as "adipokines." Adipokines play an important role in the control of human metabolism. The dysfunctional adipose tissue in obese individuals is characterized by an altered cytokine secretion pattern that promotes chronic low-grade inflammation. Epidemiological evidence highlights the association between obesity and allergic and immune-mediated diseases, such as asthma, allergic rhinitis, rheumatic arthritis, and psoriasis. Less is known about underlying pathogenic mechanisms. However, several recent in vivo and in vitro studies have reported that adipokines are involved in inflammatory and autoimmune disorders by influencing both innate and acquired immune responses. In addition, obesity has been associated with reduced immune surveillance and increased risk of cancer. This paper reviews the evidence regarding the role of adipokines in immune system regulation, with particular emphasis on autoimmune, allergic, and inflammatory disorders. Understanding how obesity affects immune system functions may enable researchers to find new potential therapeutic targets in the management of allergic and autoimmune diseases.