Eczema in early childhood is strongly associated with the development of asthma and rhinitis in a prospective cohort

Prevalence, severity, and risk factors of eczema among young children and adolescents in Saudi Arabia: A national cross-sectional study, 2019

Background

Eczema is a common inflammatory skin disease with a significant global health burden. Eczema has a significant impact on quality of life.

Objective

We aimed to estimate the prevalence, severity, and risk factors associated with eczema among schoolchildren in Saudi Arabia.

Methods

The standardized Global Asthma Network questionnaires and methodology were used to conduct a nationwide cross-sectional study across 20 regions in Saudi Arabia between March and April 2019. Data were collected from 137 primary schools and 140 intermediate schools by using a multistage stratified cluster sampling method.

Results

The study included 3614 young children aged 6 to 7 years and 4068 adolescents aged 13 to 14 years. Current eczema was prevalent among 4.5% of the children and 5.1% of the adolescents. Severe eczema was reported in 0.8% and 0.9% of the young children and adolescents, respectively. Several factors showed significant association with eczema. Among the children, eczema was linked positively to having a history of chest infections and wheezing in early life, as well as to ever attending day care and current exposure to cats. Among the adolescents, the main potential risk factors included paracetamol use in the previous year, adherence to a lifestyle of vigorous physical activity, and current exposure to cats. Conversely, high consumption of nuts was found to be negatively associated with eczema.

Conclusion

The prevalence of eczema in schoolchildren in Saudi Arabia is lower than the global average but within the average range for the Eastern Mediterranean region. Further studies in Saudi Arabia should be conducted to identify variation among different regions.

Evolution of pathologic B-cell subsets and serum environment-specific sIgEs in patients with atopic dermatitis and controls, from infancy to adulthood

BACKGROUND

While B-cells have historically been implicated in allergy development, a growing body of evidence supports their role in atopic dermatitis (AD). B-cell differentiation across ages in AD, and its relation to disease severity scores, has not been well defined.

OBJECTIVE

To compare the frequency of B-cell subsets in blood of 0-5, 6-11, 12-17, and ≥18 years old patients with AD versus age-matched controls.

METHODS

Flow cytometry was used to measure B-cell subset frequencies in the blood of 27 infants, 17 children, 11 adolescents, and 31 adults with moderate-to-severe AD and age-matched controls. IgD/CD27 and CD24/CD38 core gating systems and an 11-color flow cytometry panel were used to determine frequencies of circulating B-cell subsets. Serum total and allergen-specific IgE (sIgEs) levels were measured using ImmunoCAP®.

RESULTS

Adolescents with AD had lower frequencies of major B-cells subsets (p < .03). CD23 expression increased with age and was higher in AD compared to controls across all age groups (p < .04). In AD patients, multiple positive correlations were observed between IL-17-producing T-cells and B-cell subsets, most significantly non-switched memory (NSM) B-cells (r = .41, p = .0005). AD severity positively correlated with a list of B-cell subsets (p < .05). IL-9 levels gradually increased during childhood, reaching a peak in adolescence, paralleling allergen sensitization, particularly in severe AD. Principal component analysis of the aggregated environmental sIgE data showed that while controls across all ages tightly clustered together, adolescents with AD demonstrated distinct clustering patterns relative to controls.

CONCLUSIONS

Multiple correlations between B-cells and T-cells, as well as disease severity measures, suggest a complex interplay of immune pathways in AD. Unique B-cell signature during adolescence, with concurrent allergen sensitization and IL-9 surge, point to a potentially wider window of opportunity to implement interventions that may prevent the progression of the atopic march.

High burden of respiratory allergy in children warrants early identification and treatment with allergen immunotherapy

Respiratory allergy often begins in childhood and most commonly manifests as allergic rhinitis (upper airways) and/or asthma (lower airways). Children with upper respiratory allergy often suffer from coexisting asthma, and other comorbidities ranging from gastrointestinal disorders to emotional/mental health disorders. Consequently, the disease burden is considerable and profoundly impacts a child's daily life. Early identification and appropriate management are important to reduce disease burden, lower the risk of disease progression and additional comorbidities, and protect the child's future well-being. A window of opportunity for halting disease progression may open in the early stages of allergic disease and underlines the importance of early diagnosis and treatment of children at risk. This review offers advice on identifying children with a high disease burden who would benefit from early intervention. Allergen immunotherapy (AIT) modifies the cause of respiratory allergy and prevents disease progression. In clinical practice, AIT could be considered as an early treatment for eligible children, to achieve long-term symptom control and disease modification.

The causal relationship between immune cells and atopic dermatitis: A bidirectional Mendelian randomization study

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin condition whose origins remain unclear. Existing epidemiological evidence suggests that inflammation and immune factors play pivotal roles in the onset and progression of AD. However, previous research on the connection between immune inflammation and AD has yielded inconclusive results.

METHODS

To evaluate the causal relationship between immunological characteristics and AD, this study employed a bidirectional, two-sample Mendelian randomization (MR) approach. We utilized large-scale, publicly available genome-wide association studies to investigate the causal associations between 731 immunological feature cells and the risk of AD.

RESULTS

Significant associations were identified between six immune phenotypes and AD risk: increased Basophil %CD33dim HLA DR-CD66b-, CD25 on IgD+ CD24+, CD40 on monocytes, HLA DR on CD14+ CD16-monocytes, HLA DR on CD14+monocytes correlated with higher AD risk, while elevated CD3 on CD4 Treg was linked to lower risk. Reverse MR analysis revealed AD as a risk factor for IgD+ CD38br AC and IgD+ CD38br %B cell, but a protective factor against CD20 on IgD+ CD38- naive and CD8 on NKT.

CONCLUSION

Our findings elucidate the intricate interplay between immune cells and AD, informing future research into AD pathophysiology and therapeutics.

Transcriptomic evaluation of skin tape-strips in children with allergic asthma uncovers epidermal barrier dysfunction and asthma-associated biomarkers abnormalities

INTRODUCTION

Tape-strips, a minimally invasive method validated for the evaluation of several skin diseases, may help identify asthma-specific biomarkers in the skin of children with allergic asthma.

METHODS

Skin tape-strips were obtained and analyzed with RNA-Seq from children with moderate allergic asthma (MAA) (n = 11, mean age 7.00; SD = 1.67), severe allergic asthma (SAA) (n = 9, mean age 9.11; SD = 2.37), and healthy controls (HCs) (n = 12, mean age 7.36; SD = 2.03). Differentially expressed genes (DEGs) were identified by fold change ≥2 with a false discovery rate <0.05. Transcriptomic biomarkers were analyzed for their accuracy in distinguishing asthma from HCs, their relationships with asthma-related outcomes (exacerbation rate, lung function-FEV1, IOS-R5-20, and lung inflammation-FeNO), and their links to skin (barrier and immune response) and lung (remodeling, metabolism, aging) pathogenetic pathways.

RESULTS

RNA-Seq captured 1113 in MAA and 2117 DEGs in SAA. Epidermal transcriptomic biomarkers for terminal differentiation (FLG/filaggrin), cell adhesion (CDH19, JAM2), lipid biosynthesis/metabolism (ACOT2, LOXL2) were significantly downregulated. Gene set variation analysis revealed enrichment of Th1/IFNγ pathways (p < .01). MAA and SAA shared downregulation of G-protein-coupled receptor (OR4A16, TAS1R3), upregulation of TGF-β/ErbB signaling-related (ACVR1B, EGFR, ID1/2), and upregulation of mitochondrial-related (HIGD2A, VDAC3, NDUFB9) genes. Skin transcriptomic biomarkers correlated with the annualized exacerbation rate and with lung function parameters. A two-gene classifier (TSSC4-FAM212B) was able to differentiate asthma from HCs with 100% accuracy.

CONCLUSION

Tape-strips detected epithelial barrier and asthma-associated signatures in normal-appearing skin from children with allergic asthma and may serve as an alternative to invasive approaches for evaluating asthma endotypes.

Infant lung function and early skin barrier impairment in the development of asthma at age 3 years

BACKGROUND

Largely unexplored, we investigated if lower lung function, impaired skin barrier function by transepidermal water loss (TEWL), eczema, and filaggrin (FLG) mutations in infancy were associated with asthma in early childhood.

METHODS

From the factorially designed randomized controlled intervention study PreventADALL, we evaluated 1337/2394 children from all randomization groups with information on asthma at age 3 years, and at age 3 months either lung function, TEWL, eczema, and/or FLG mutations. Lower lung function was defined as the time to peak tidal expiratory flow to expiratory time (tPTEF /tE ) <0.25, and skin barrier impairment as a high TEWL >9.50 g/m2 /h. Eczema was clinically observed, and DNA genotyped for FLG mutations. Asthma was defined as asthma-like symptoms (≥3 episodes of bronchial obstruction) between age 2-3 years as well as a history of doctor-diagnosed asthma and/or asthma medication use. Associations were analyzed in logistic regression models, presented with adjusted ORs (aOR) and 95% confidence intervals (CI).

RESULTS

Lower lung function and skin barrier impairment were associated with asthma in general; aOR (95% CI) 5.4 (2.1, 13.7) and 1.6 (1.1, 2.5), while eczema and FLG mutations were associated with asthma in children with atopic dermatitis or allergic sensitization only. Stratifying for sex, the risk of asthma was only increased in boys with lower lung function; aOR (95% CI) 7.7 (2.5, 23.6), and in girls with FLG mutations; aOR (95% CI) 3.5 (1.5, 8.2).

CONCLUSION

Lower lung function and impaired skin barrier function in infancy may increase the risk of asthma at age 3 years.

Incident Asthma, Asthma Exacerbations, and Asthma-Related Hospitalizations in Patients With Atopic Dermatitis

BACKGROUND

Atopic dermatitis (AD) is thought to induce asthma via the "atopic march," but the effects of AD on incident asthma and asthma severity have not been fully characterized.

OBJECTIVE

To determine risk of asthma, asthma exacerbations, and asthma-related hospitalizations among patients fwith AD.

METHODS

A cohort study was conducted using electronic health records data from UK general practices from 1994 to 2015. Children (<18 years old) and adults (≥18 years) with AD were matched on age, practice, and index date to patients without AD. AD severity was categorized using treatments and dermatologist referrals. Outcomes were incident asthma among all patients and asthma exacerbation or hospitalization among patients with asthma.

RESULTS

On comparing 409,341 children with AD (93.2% mild, 5.5% moderate, 1.3% severe) with 1,809,029 unaffected children, those with AD were found to be associated with a 2-fold greater risk of asthma compared with those without AD (hazard ratio, 1.96; 95% CI, 1.93-1.98). On comparing 625,083 adults with AD (65.7% mild, 31.4% moderate, and 2.9% severe) with 2,678,888 unaffected adults, AD was found to be associated with a 38% higher risk of asthma (hazard ratio, 1.38; 95% CI, 1.36-1.40). Asthmatic patients with AD also had a 21% to 63% greater risk of asthma exacerbations and a 20% to 64% greater risk of asthma-related hospitalizations compared with asthmatic patients without AD. Risk of asthma, asthma exacerbation, or asthma-related hospitalization increased with AD severity in a dose-dependent manner in both the pediatric and adult cohorts.

CONCLUSIONS

AD, especially in children and when more severe, is associated with greater risk of asthma as well as greater risk of asthma exacerbations and hospitalizations among asthmatic patients.

Modification of Food Allergy on the Associations between Early Life Exposure to Size-Specific Particulate Matter and Childhood Allergic Rhinitis

Previous studies have reported the association between particulate matter (PM) and childhood allergic rhinitis (AR). However, it is unclear whether food allergy (FA) modifies the PM-AR association. We aimed at evaluating the effect of the modification of FA on PM-AR association in preschool children. We adopted a cross-sectional study and conducted a questionnaire survey among preschool children aged 3-6 years in 7 cities in China from June 2019 to June 2020 to collect information on AR and FA. We used a combination of multilevel logistic regression and restricted cubic spline functions to quantitatively assess whether FA modifies the associations between size-specific PM exposure (1 × 1 km) and the risk of AR. The adjusted odds ratios (ORs) for AR among the children with FA as per a 10 μg/m3 increase in early life PM1, PM2.5, and PM10 were significantly higher than the corresponding ORs among the children without FA [e.g., OR: 1.58, 95% CI: (1.32, 1.90) vs 1.29, 95% CI: (1.18, 1.41), per 10 μg/m3 increase in PM1]. The interactions between FA and size-specific PM exposure and their effects on AR were statistically significant (all p-int < 0.001). FA, as an important part of the allergic disease progression, may modify the PM-AR association in preschool children.

Health effects associated with exposure to secondhand smoke: a Burden of Proof study

Despite a gradual decline in smoking rates over time, exposure to secondhand smoke (SHS) continues to cause harm to nonsmokers, who are disproportionately children and women living in low- and middle-income countries. We comprehensively reviewed the literature published by July 2022 concerning the adverse impacts of SHS exposure on nine health outcomes. Following, we quantified each exposure-response association accounting for various sources of uncertainty and evaluated the strength of the evidence supporting our analyses using the Burden of Proof Risk Function methodology. We found all nine health outcomes to be associated with SHS exposure. We conservatively estimated that SHS increases the risk of ischemic heart disease, stroke, type 2 diabetes and lung cancer by at least around 8%, 5%, 1% and 1%, respectively, with the evidence supporting these harmful associations rated as weak (two stars). The evidence supporting the harmful associations between SHS and otitis media, asthma, lower respiratory infections, breast cancer and chronic obstructive pulmonary disease was weaker (one star). Despite the weak underlying evidence for these associations, our results reinforce the harmful effects of SHS on health and the need to prioritize advancing efforts to reduce active and passive smoking through a combination of public health policies and education initiatives.

Defining and Measuring the Scope of Atopic Dermatitis

Atopic dermatitis (AD) has no definitive diagnostic test and has a large range of phenotypes, making it a difficult disease to assess and define. However, an agreed-upon definition of AD is important for clinical trials, population-based studies, and clinical practice. Several diagnostic criteria systems have been proposed to fill these needs, with none considered the gold standard. To further aid in standardized assessment of AD patients, numerous disease severity and quality-of-life measurement tools have been proposed. There is similarly no gold standard and efforts are ongoing to develop a single consensus scale. Finally, assessment of AD-associated comorbidities, including allergic/immunologic conditions, psychiatric disorders, and metabolic/cardiac conditions, is important when evaluating this patient population.

Atopic March or Atopic Multimorbidity-Overview of Current Research

The atopic march encompasses a sequence of allergic conditions, including atopic dermatitis, food allergy, allergic rhinitis, and asthma, that frequently develop in a sequential pattern within the same individual. It was introduced as a conceptual framework aimed at elucidating the developmental trajectory of allergic conditions during childhood. Following the introduction of this concept, it was initially believed that the atopic march represented the sole and definitive trajectory of the development of allergic diseases. However, this perspective evolved with the emergence of new longitudinal studies, which revealed that the evolution of allergic diseases is far more intricate. It involves numerous immunological pathological mechanisms and may not align entirely with the traditional concept of the atopic march. The objective of our review is to portray the atopic march alongside other patterns in the development of childhood allergic diseases, with a specific emphasis on the potential for a personalized approach to the prevention, diagnosis, and treatment of atopic conditions.

Allergic Rhinitis

Allergic rhinitis (AR) affects more than 400 million people worldwide, making it 1 of the most prevalent chronic diseases. Childhood AR is increasing, and almost half of patients with AR develop symptoms before age 6 years. Although a diagnosis of AR is associated with higher socioeconomic status, underserved and urban populations have more indoor aeroallergen sensitizations and are likely underdiagnosed with AR, further exacerbating health-care disparities. AR negatively impacts quality of life, school performance, and overall health outcomes. Untreated AR in children increases the risk for poor asthma control, increased asthma severity, and exacerbations. Many patients believe that they have seasonal allergies only but in reality have both perennial and seasonal AR, which may change the approach to allergen avoidance measures and treatment recommendations. Pharmacotherapy of AR has expanded, with many intranasal corticosteroids, intranasal antihistamines, and second-generation oral antihistamines approved for pediatric use. Allergen immunotherapy, including both subcutaneous and sublingual forms, are approved for children and are disease modifying, potentially reducing further allergen sensitization and progression to asthma. Many of the currently available biological therapies indicated for pediatric asthma and/or atopic diseases reduce AR symptoms as well. Children with moderate to severe or refractory AR or those with comorbidities should be referred to allergists for diagnostic testing and expanded management options, including immunotherapy and potential biological treatment.

Assessment of Subclinical Atherosclerosis in Children with Atopic Dermatitis

INTRODUCTION

Data from studies conducted to date have evaluated clinical atherosclerotic conditions in adult patients with atopic dermatitis (AD). Subclinical atherosclerotic changes that are a precursor of atherosclerotic conditions may begin in childhood. The aim of this study was to investigate the presence of subclinical atherosclerosis in pediatric patients with AD and to determine the associated risk factors.

METHODS

A total of 59 patients who were referred to our department over a 6-month period and diagnosed with AD, and 53 healthy controls with a similar age and gender were included in the study. Subclinical atherosclerosis markers (carotid intima media thickness [CIMT], distensibility, stiffness, and strain) were measured using conventional echocardiography. The patients' age, SCORAD index, and duration of symptoms were recorded. Serum total immunoglobulin E, C-reactive protein (CRP), blood lipid profile, and complete blood count markers were measured.

RESULTS

The median age of the patients was 61 (10-103) months, and 59.3% of them were male. The patients with AD had a higher CIMT (1.60 ± 0.35 vs. 1.30 ± 0.50 mm) and a lower distensibility (0.006 ± 0.009 vs. 0.01 ± 0.008) and strain (0.10 ± 0.14 vs. 0.19 ± 0.14) than the healthy controls (p < 0.01 for all), but there was no significant difference with regard to stiffness (10.16 ± 21.75 vs. 8.99 ± 12.66). Significant correlations between CIMT and disease duration, age, and the SCORAD index were found (p < 0.01, p < 0.01, and p < 0.05, respectively). No correlation between the subclinical atherosclerosis markers and the other laboratory results was found (p > 0.05 for all).

CONCLUSION

This study demonstrates that pediatric patients with AD may express subclinical atherosclerosis markers. The evaluation of subclinical atherosclerosis in these patients revealed that CIMT may be the most important marker, as it displayed positive correlations with symptom duration, age, and disease severity.

National situation, trends, and predictions of disease burden of atopic dermatitis in Chinese children and adolescents

Background

Atopic dermatitis (AD) is an important global health problem affecting children and adolescents and detailed national information of disease burden in China is lacking. We aimed to evaluate the national disease burden of AD in Chinese children and adolescent, to provide the temporal trends over the past 30 years and to predict the burden for the next 10 years.

Methods

The data of AD in China, including incidence, prevalence, and DALY, and population data were obtained from the Global Burden of Disease Study 2019 (GBD study 2019), which were estimated using the DisMod-MR 2.1. We analyzed the three measures by age and sex; the age groups were <5 years, 5-9 years, 10-14 years, and 15-19 years. The joinpoint regression analyses was conducted to assess the temporal trends from 1990 to 2019. The Bayesian age-period cohort (BAPC) model was used to predict measures from 2020 to 2030.

Results

In 2019, the highest incidence case and rate were observed in <5 years group; for prevalence and disability adjusted life year (DALY), the groups of <5 years and 5-9 years showed similar higher levels and the groups of 10-14 years and 15-19 years had similar relatively lower levels. Overall, the male-to-female ratios were >1 in <5 years group and <1 in 10-14 and 15-19 age groups. The trend analyses found an overall trend of decrease in cases of the three measures; in recent about 3 years, slight increase trends were shown in cases and rates of the three measures in <5 years group. The prediction analyses found a slight decreasing trend for cases of these measures and a slight increasing trend for rates of these measures in the <5 years group in the next 10 years; the 5-9 years group was predicted to increase slightly in rates of the three measures.

Conclusion

In conclusion, the groups of <5 years and 5-9 years are two important populations that need targeted measures to reduce disease burden of AD in China. Regarding sex disparity, we should pay more attention to males in <5 years group and to females in 10-19 years group.

Association of soap use when bathing 18-month-old infants with the prevalence of allergic diseases at age 3 years: The Japan Environment and Children's Study

BACKGROUND

Atopic march is defined as the progression from atopic dermatitis (AD) during early life to other allergic diseases in later childhood. In a nationwide birth cohort study, the Japan Environment and Children's Study, we investigated the association of bathing habits, which are known to affect skin conditions, for infants with their later development of allergic diseases.

METHODS

Pregnant women who lived in 15 designated regional centers throughout Japan were recruited. We obtained information on bathing habits for their 18-month-old infants and the prevalence of allergic diseases when they were aged 3 years.

RESULTS

Data for 74,349 children were analyzed. Most 18-month-old infants were bathed or showered almost every day. When they were divided into four groups according to the frequency of soap use during bathing (every time, most of the time, sometimes, and seldom), the risk of AD later at age 3 was shown to increase in association with a decreasing frequency of soap use [most of the time: adjusted odds ratio (aOR) 1.18, 95% confidence interval (CI) 1.05-1.34; sometimes: aOR 1.72, 95% CI 1.46-2.03; seldom: aOR 1.99, 95% CI 1.58-2.50], compared with soap use every time during bathing at 18 months of age. Similar results were obtained for food allergy but not for bronchial asthma.

CONCLUSIONS

Frequent soap use when bathing 18-month-old infants was associated with a decreased risk of them developing allergic diseases at age 3. Further well-designed clinical studies are warranted to determine an effective bathing regimen for preventing the development of allergic diseases.

Multimorbidity of Allergic Conditions in Urban Citizens of Southern China: A Real-World Cross-Sectional Study

Background: Extensive knowledge of allergic multimorbidities is required to improve the management of allergic diseases with the industrialization of China. However, the demography and allergen distribution patterns of allergic multimorbidities in China remain unclear, despite the increasing prevalence of allergies. Methods: This was a real-world, cross-sectional study of 1273 outpatients diagnosed with one or more allergic diseases in Guangzhou, the most populated city of southern China, with leading industrial and commercial centers, between April 2021 and March 2022. Seven allergic diseases (allergic rhinitis (AR), asthma (AS)/cough variant asthma (CVA), atopic dermatitis (AD)/eczema, food allergy (FA), allergic conjunctivitis (AC), drug allergy (DA), and anaphylaxis) were assessed. Positive rates of sensitization to different allergens were measured using an allergen detection system of the UniCAP (Pharmacia Diagnostics, Sweden) instrument platform to compare the groups of allergic multimorbidities against a single entity. Results: There were 659 (51.8%) males and 614 (48.2%) females aged from 4 months to 74 years included in the analysis. The study participants who were diagnosed with allergic diseases had an average of 1.6 diagnoses. Overall, 46.5% (592 of 1273) of the patients had more than one allergic condition, and allergic rhinitis was the most common type of multimorbidity. Women were more likely to suffer from an allergic disease alone, whereas allergic multimorbidities were more likely to be diagnosed in men (p = 0.005). In addition, allergic multimorbidities were common in all age groups, with an incidence ranging from 37.1% to 57.4%, in which children and adolescents were more frequently diagnosed with allergic multimorbidities than adults (18–60 years old) (all p < 0.05). Allergic multimorbidity was observed throughout the year. A difference in the positive rate of allergens sensitization and total immunoglobulin E (tIgE) levels between different allergic multimorbidities was observed. Conclusions: Allergic multimorbidities were very commonly found in nearly half of all patients with allergies. The proportion of allergic multimorbidities varied with the type of disease, sex, age, and allergen distribution pattern. These findings may help clinicians to develop “One health” strategies for the clinical management of allergic diseases.

Attenuating the atopic march: Meta-analysis of the dupilumab atopic dermatitis database for incident allergic events

BACKGROUND

Atopic march refers to the sequential development of allergic diseases from infancy through adolescence, typically beginning with atopic dermatitis (AD), followed by food allergy and then airway diseases, later evolving to broader or worsened spectrum of allergic diatheses. No intervention has shown to alter its course.

OBJECTIVE

We sought to determine the rate of acquisition of new or worsened allergic events for dupilumab versus placebo in patients with AD.

METHODS

Allergy-associated events from 12 clinical trials were grouped into 17 allergy categories, and IgE changes from baseline were defined. A new/worsened event was considered one step of atopic march. Treatment effect was assessed by incidence rate ratios (IRRs), dupilumab versus placebo, by meta-analysis.

RESULTS

The duration of pooled AD studies was 4 to 52 weeks (1359 patient-years; n = 2296 dupilumab, n = 1229 placebo, median age 35 years). The median age at AD onset was 2 years. Baseline allergic disease burden was comparable between groups. Dupilumab reduced the risk of new/worsening allergies by 34% (IRR 0.66; 95% confidence interval [CI], 0.52-0.84) and new allergies by 37% (IRR 0.63; 95% CI, 0.48-0.83) versus placebo. Including IgE category shift, the IRR for combined new/worsening allergies was reduced by 54% (IRR 0.46; 95% CI, 0.36-0.57). These treatment benefits did not reverse on treatment discontinuation in off-treatment follow-up.

CONCLUSIONS

The acquisition/worsening of allergic conditions suggestive of atopic march was observed in a pooled adult/adolescent AD study population with inadequately controlled AD. Treatment with dupilumab reduced new/worsened allergy events versus placebo; inclusion of IgE category change increased the apparent benefit.

Eczema phenotypes and IgE component sensitization in adolescents: A population-based birth cohort

BACKGROUND

Eczema patients are commonly immunoglobulin (Ig)E polysensitized. Although atopic dermatitis (AD) phenotypes have been recognized, IgE sensitization patterns based on AD phenotypes have not been well illustrated. We aimed to investigate how eczema phenotypes impact IgE component sensitization patterns.

METHODS

This birth cohort study investigated a general population in the Tokyo Children's Health, Illness, and Development Study (T-Child Study) until children reached the age of 13 years. Eczema was assessed using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Allergen component specific IgE antibody titers were measured using a multiplex array ImmunoCAP ISAC.

RESULTS

Persistent eczema phenotype until adolescence was strongly associated with allergic march symptoms, such as wheezing and hay fever, and oral allergy symptoms, and IgE component sensitizations of airborne (Japanese cedar, house dust mite, Timothy, cat, and dog) and cross-reactive allergens (Bet v 1 family) compared to early-remission and late-onset eczema. On the other hand, late-onset eczema did not show any strong associations with allergic symptoms and IgE sensitization. Adolescents with persistent eczema have high comorbidity of symptoms of pollen-food allergy syndrome.

CONCLUSIONS

Early-onset eczema is deeply connected with the later allergic march, and late-onset eczema differs from the phenotype of allergic march. Early-onset eczema characterizing IgE sensitization was likely to be an extrinsic type, and late-onset eczema, which was not related to IgE sensitization, was likely an intrinsic type. Pollen-Food Allergy Syndrome is one of the allergic features in allergic march.

High baseline prevalence of atopic comorbidities and medication use in children treated with allergy immunotherapy in the REAl-world effeCtiveness in allergy immunoTherapy (REACT) study

Background

Respiratory allergy, commonly manifesting as allergic rhinitis (AR) and asthma, is a chronic progressive disease that frequently starts in childhood. Allergy immunotherapy (AIT) is the only causal treatment for respiratory allergy with the potential to modify the underlying cause of allergy and, ultimately, prevent disease progression. This analysis aimed to determine if AIT is received sufficiently early to halt the progression of allergic disease, by characterizing the burden and progression of disease in children prior to AIT initiation in real-life clinical practice.

Methods

The REAl-world effeCtiveness in allergy immunoTherapy (REACT) study was a large retrospective cohort study using German claims data between 2007 and 2017. Characteristics of two pre-defined AIT age cohorts from the REACT study - children (aged <18 years) and adults (aged ≥18 years) - were evaluated during the 1-year period before the first AIT prescription. For comparison, a control group of all subjects with a confirmed diagnosis of AR and without prescriptions for AIT was included. Burden of disease was assessed using diagnostic codes for atopic comorbidities [e.g., atopic dermatitis (AD), asthma, and acute allergic conjunctivitis] and non-atopic comorbidities (e.g., migraine, headache); medication use, recorded as prescriptions for symptom-relieving AR medication and reliever/controller medication for asthma, was also assessed. Data were analyzed descriptively, using summary statistics.

Results

Both children (n = 11,036) and adults (n = 30,037) showed a higher prevalence of atopic comorbidities and a greater drug burden prior to AIT initiation compared to AR patients not treated with AIT (n = 1,003,332). In the two age-specific AIT cohorts, children consistently showed the highest prevalence of atopic comorbidities compared to adults (AIT children, AIT adults - asthma: 41.4%, 34.5%; AD: 19.9%, 10.2%; acute allergic conjunctivitis: 13.6%, 10.2%). Generally, prescriptions per year for symptom-relieving AR and asthma treatments were also higher for children initiating AIT vs. adults (AIT children, AIT adults - AR prescriptions per subject: 1.72, 0.73; asthma prescriptions per subject: 1.42, 0.79).

Conclusions

Children with AR who are offered AIT in real-life show considerable disease burden prior to initiation. As AIT may alleviate the burden and halt the progression of allergic disease, considering AIT earlier in the disease course may be warranted.

Risk Factors Affecting Development and Persistence of Preschool Wheezing: Consensus Document of the Emilia-Romagna Asthma (ERA) Study Group

Wheezing at preschool age (i.e., before the age of six) is common, occurring in about 30% of children before the age of three. In terms of health care burden, preschool children with wheeze show double the rate of access to the emergency department and five times the rate of hospital admissions compared with school-age asthmatics. The consensus document aims to analyse the underlying mechanisms involved in the pathogenesis of preschool wheezing and define the risk factors (i.e., allergy, atopy, infection, bronchiolitis, genetics, indoor and outdoor pollution, tobacco smoke exposure, obesity, prematurity) and the protective factors (i.e., probiotics, breastfeeding, vitamin D, influenza vaccination, non-specific immunomodulators) associated with the development of the disease in the young child. A multidisciplinary panel of experts from the Emilia-Romagna Region, Italy, addressed twelve key questions regarding managing preschool wheezing. Clinical questions have been formulated by the expert panel using the PICO format (Patients, Intervention, Comparison, Outcomes). Systematic reviews have been conducted on PubMed to answer these specific questions and formulate recommendations. The GRADE approach has been used for each selected paper to assess the quality of the evidence and the degree of recommendations. Based on a panel of experts and extensive updated literature, this consensus document provides insight into the pathogenesis, risk and protective factors associated with the development and persistence of preschool wheezing. Undoubtedly, more research is needed to improve our understanding of the disease and confirm the associations between certain factors and the risk of wheezing in early life. In addition, preventive strategies must be promoted to avoid children's exposure to risk factors that may permanently affect respiratory health.

The prenatal and postnatal effects of air pollution on asthma in children with atopic dermatitis

OBJECTIVES

Air pollution is strongly associated with asthma, but has not been determined to induce new-onset asthma development in children with atopic dermatitis (AD).

WORKING HYPOTHESIS

To assess whether prenatal/postnatal exposure to air pollutants triggers new-onset asthma development in children with AD.

STUDY DESIGN

Retrospective cohort study.

PATIENT-SUBJECT SELECTION

Data of patients <age 18 years diagnosed with eczema or AD between 2009 and 2019 were extracted from the multicenter Kaohsiung Medical University Hospital Research Database. Patients diagnosed with new-onset asthma were in the asthma group and patients without asthma history were in the non-asthma group.

METHODOLOGY

The monthly average concentration of air pollutants for 1, 3, and 5 years before the index date, and 3, 6, and 9 months prenatally were analyzed and further stratified by age, immunoglobulin (Ig) E, and the percentage of eosinophil and eosinophil cationic protein (ECP).

RESULTS

Postnatal exposure to airborne particulate matter (PM_2.5 , PM₁₀ ), sulfur dioxide (SO₂ ), ozone (O₃ ), carbon monoxide (CO), nitric oxide (NO), nitric dioxide (NO₂ ), and NO_x , and prenatal exposure to PM_2.5 , PM₁₀ , SO₂ , NO, and NO_x were significantly higher in the asthma group than in the non-asthma group. Patients having IgE above 100 IU/ml and ECP less than 24 ng/ml were significantly influenced by postnatal exposure to PM_2.5 and PM₁₀ , especially CO, to develop asthma, and those having an eosinophil count >3% were significantly influenced by prenatal exposure to PM_2.5 , especially SO₂ , NO, and NO₂ .

CONCLUSIONS

Prenatal and postnatal exposure to air pollution have an association with asthma development in AD patients.

Genome-Wide Integration of Genetic and Genomic Studies of Atopic Dermatitis: Insights into Genetic Architecture and Pathogenesis

Atopic dermatitis (AD) is a common heterogeneous, chronic, itching, and inflammatory skin disease. Genetic studies have identified multiple AD susceptibility genes. However, the genetic architecture of AD has not been elucidated. In this study, we conducted a large-scale meta-analysis of AD (35,647 cases and 1,013,885 controls) to characterize the genetic basis of AD. The heritability of AD in different datasets varied from 0.6 to 7.1%. We identified 31 previously unreported genes by integrating multiomics data. Among the 31 genes, MCL1 was identified as a potential treatment target for AD by mediating gene‒drug interactions. Tissue enrichment analyses and phenome-wide association study provided strong support for the role of the hemic and immune systems in AD. Across 1,207 complex traits and diseases, genetic correlations indicated that AD shared links with multiple respiratory phenotypes. The phenome-wide Mendelian randomization analysis (Mendelian randomization‒phenome-wide association study) revealed that the age of onset of diabetes exhibited a positive causal effect on AD (inverse-variance weighted β = 0.39, SEM = 0.09, P = 2.77 × 10^-5). Overall, these results provide important insights into the genetic architecture of AD and will lead to a more thorough and complete understanding of the molecular mechanisms underlying AD.

Atopic Dermatitis With Coexisting Food Allergy in Early Life Is Associated With Childhood Asthma

PURPOSE

Atopic dermatitis (AD) and food allergy (FA) are associated with respiratory comorbidities, in the concept of 'atopic march.' However, children with AD and a coexisting FA have various disease courses, and the mechanism of atopic march remains unclear. In this study, we investigated whether the phenotype of AD with coexisting FA in early life affected asthma or allergic rhinitis (AR) in school children.

METHODS

A total of 1,579 children from the Panel Study on Korean Children (PSKC) cohort were followed-up in 2013. The participants diagnosed with AD in this cohort were classified by the age of AD onset and persistence as well as FA history. We compared the presence of comorbidities-asthma and rhinitis-among different AD phenotypes.

RESULTS

Asthma and AR with current symptoms within 12 months at age 6-8 years were associated with early-onset persistent AD phenotype, regardless of coexisting FA. AD with FA conferred a higher risk of recent wheezing at 8 years of age than AD without FA (adjusted odds ratio, 8.09; 95% confidence interval, 2.54-25.76). Children with early-onset persistent AD with FA manifested a distinctive trajectory with a higher prevalence of wheezing and AR at age 5-8 years than those without AD.

CONCLUSIONS

AD with FA in early life is strongly associated with asthma and AR in school children, and the early-onset persistent AD with FA had a strong additive effect on the risk of asthma at school age. Classifying AD phenotypes regarding FA in early life will help predict and prevent asthma and AR in school children.

Context-dependent function of TSLP and IL-1β in skin allergic sensitization and atopic march

Atopic diseases, including atopic dermatitis (AD) and asthma, affect a large proportion of the population, with increasing prevalence worldwide. AD often precedes the development of asthma, known as the atopic march. Allergen sensitization developed through the barrier-defective skin of AD has been recognized to be a critical step leading to asthma, in which thymic stromal lymphopoietin (TSLP) was previously shown to be critical. In this study, using a laser-assistant microporation system to disrupt targeted skin layers for generating micropores at a precise anatomic depth of mouse skin, we model allergen exposure superficially or deeply in the skin, leading to epicutaneous sensitization or dermacutaneous sensitization that is associated with a different cytokine microenvironment. Our work shows a differential requirement for TSLP in these two contexts, and identifies an important function for IL-1β, which is independent of TSLP, in promoting allergen sensitization and subsequent allergic asthma.

Allergic sensitisation in the skin can lead to allergic dermatitis and further to airway asthma in a process of atopic march. Here the authors examine the difference between superficial or deep skin sensitisation, characterise the immune cells generated and show differential TSLP and IL-1β involvement.

Adults with concomitant atopic dermatitis and asthma have more frequent urgent health care utilization and less frequent scheduled follow-up visits than adults with atopic dermatitis or asthma only: A nationwide cohort study

BACKGROUND

Atopic dermatitis (AD) and asthma often co-occur in the same patient, and health care utilization is related to disease severity of these diseases.

OBJECTIVE

To investigate differences in healthcare utilization in adults with concomitant AD and asthma compared to patients with asthma or AD only.

METHODS

All Danish adults with a hospital-diagnosis of AD, asthma or concomitant AD and asthma recorded in national registries were included. Health care utilization data were obtained in 3-month intervals from two year prior to index date (the date of the first hospital diagnosis), and to five years after.

RESULTS

A total of 12,409 patients with AD were included (11,590 with AD only and 819 with concomitant AD and asthma), and 65,539 with asthma only. Adults with concomitant AD and asthma had higher risk of hospitalization for AD (OR 1.38, 95% CI (1.15-1.67), p=0.001) and asthma (OR 1.16, 95% CI (1.00-1.35), p=0.047) compared to patients with only AD and asthma, respectively. These patients also had fewer visits in outpatient clinics for AD (OR 0.10, 95% CI (0.08-0.12), p<0.001) and asthma (OR 0.34, 95% CI (0.29-0.39), P<0.001) compared to patients with only AD or asthma. Outpatient clinic visits for rhinitis were more frequent among patients with concomitant AD and asthma compared to patients with only AD or asthma.

CONCLUSION

Adults with concomitant AD and asthma had different patterns of healthcare utilization compared to adults with AD or asthma alone, suggesting that improvements in management and monitoring may reduce unscheduled health care visits, and lower healthcare costs.

Time-trends for eczema prevalences among children and adults from 1985 to 2015 in China: a systematic review

Background

Several studies have reported that childhood prevalence of eczema has been increasing worldwide. However, none study quantitatively evaluated prevalence trends of eczema among children and adults in the last 30 years in China.

Methods and Findings

Via a systematic review of literature databases in English and Chinese, we summarized all studies reporting eczema prevalences from 1985 to 2015 in China as well as diagramed prevalence and eczematous population trends against year for different age groups. A total of 93 studies and 17 studies (16 for children and one for adults) were selected for qualitative and quantitative synthesis, respectively. Childhood lifetime-ever eczema prevalences ranged from 10.0% to 30.0%. Prevalences among 3-12-year-olds children showed increasing trends in most specific cities, but national lifetime-ever eczema prevalences among 13-14-year-olds children decreased from 10.6% in 2001 to 8.6% in 2009 in mainland China. We estimated that about 1.5 million children aged 13-14-year-olds in 2009 and 15.5 million children aged 3-6-year-olds in 2012 had lifetime-ever eczema in mainland China. Similar studies were too few to ascertain time-trends of eczema prevalence among adults. About 39.4, 20.0, and 11.6 million adults aged 15-86-year-olds in 2010 had contact dermatitis, seborrheic dermatitis, and atopic dermatitis in the mainland China, respectively.

Conclusions

The burden of eczema became heavier in young children, whereas perhaps had been reduced in adolescent in China. More studies for eczema prevalence in adults are warranted.

Global Asthma Network Phase I, India: Results for allergic rhinitis and eczema in 127,309 children and adults

Background

The Global Asthma Network phase I study in India aimed to study the prevalence, time trends, and associated risk factors of allergic rhinitis and eczema among 6-7-year-old, and 13-14-year-old school children and their parents. Objectives: The objective of the study was to understand the current prevalence and associated risk factors of Allergic Rhinitis and Eczema in India among 6-7-year-olds, 13-14-year-olds and in their parents/guardians for newer directions to health care providers, policy makers and academicians.

Methods

Cross-sectional, multicenter study using self- and parent-administered questionnaire among randomly selected school children aged 6 to 7 years from 8 centers and 13 to 14 years from 9 centers and their respective parents/guardians across India.

Results

Prevalence of allergic rhinitis (AR) (%, 95% CI) among 20,084 6-7-year-olds (children), 25,887 13-14-year-olds (adolescents), and 81,296 adults/parents was 7.7% (7.4%-8.1%), 23.5% (23.0%-24.1%), and 9.8% (9.55%-9.96%) and that of eczema was 2.5% (2.3%-2.7%), 3.5% (3.27%-3.71%), and 9.9% (9.7%-10.1%), respectively. Among 6-7-year-olds, AR and eczema showed a significantly (P < .001) declining time trend since the International Study of Asthma and Allergies in school children phase III in 2002-2003. Among 13-14-year-olds, AR (P < .01) but not eczema showed a significant temporal decline. Coexisting atopic condition, parental history of atopy, and some environmental factors consistent with previous studies were significant risk factors among children and adolescents. AR or eczema in either parent strongly predicted the same atopic condition among their adolescent offspring. Among adults, coexisting atopic condition was the strongest predictor of either AR or eczema.

Conclusions

There is a slight declining time trend of AR and eczema in India over 2 decades among children and adolescents. Nearly 10% of Indian adults suffer from AR and eczema. Although genetic factors had the strongest association for AR and eczema among all age groups, certain early-life and environmental exposures need consideration to devise preventative strategies.

Increasing severity of early-onset atopic dermatitis, but not late-onset, associates with development of aeroallergen sensitization and allergic rhinitis in childhood

BACKGROUND

Early exposure to allergens through a defect skin barrier has been proposed as a mechanism for inducing sensitization and development of allergic diseases. We hypothesized that early-onset, severe atopic dermatitis (AD) is associated with development of aeroallergen sensitization and allergic rhinitis.

METHODS

We included 368 children from the Copenhagen Prospective Studies on Asthma in Childhood₂₀₀₀ (COPSAC₂₀₀₀ ) at-risk mother-child cohort. AD was diagnosed prospectively based on Hanifin&Rajka's criteria and severity assessed using the Scoring Atopic Dermatitis (SCORAD) index. Early-onset AD was defined as debut ≤1 year, late-onset as debut from 1-6 years. Aeroallergen sensitization and allergic rhinitis were diagnosed at ages 6-7 and 12 years. Associations between early-onset and late-onset AD and allergy endpoints were calculated using general estimating equations (GEE) models to compute the overall odds ratios (OR) for both time points.

RESULTS

Early-onset AD (yes/no) and severity (SCORAD) were associated with development of aeroallergen sensitization during childhood; GEE OR = 1.68 [1.08; 2.62], p = .02 and 1.08 [1.03; 1.12], p < .001, whereas late-onset AD showed a borderline significant association and late-onset severity showed no association; GEE OR = 1.65 [0.92; 2.94], p = .08 and 1.01 [0.97; 1.06], p = .55. The same trend was seen for allergic rhinitis with significant association between early-onset AD and allergic rhinitis; GEE OR = 1.56 [1.01; 2.41], p = .04 and severity; GEE OR = 1.09 [1.05; 1.13], p < .001, whereas late-onset AD showed no association. The effects on sensitization and rhinitis of early-onset versus late-onset AD severity were significantly different: p-interaction_{sensitization}  = .03 and p-interaction_rhinitis  < .01.

CONCLUSION

Increasing severity of early-onset AD, but not late-onset AD, associates with aeroallergen sensitization and allergic rhinitis later in childhood.

Establishing subclasses of childhood eczema, their risk factors and prognosis

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.

Clinical Characteristics of Atopic Dermatitis in Korean School-Aged Children and Adolescents According to Onset Age and Severity

BACKGROUND

Atopic dermatitis (AD) is a heterogeneous disease with different age of onset, disease course, clinical symptoms, severity, and risk of comorbidity. The characteristics of children with AD also vary by age or country. However, little is known about the clinical characteristics of AD in Korean school-aged children and adolescents. Furthermore, there are few studies on phenotypic differences according to onset age. This study aimed to explore the clinical characteristics and phenotypes according to onset age and severity of AD in children and adolescents in Korea.

METHODS

AD patients aged 6-18 years who presented to 18 hospitals nationwide were surveyed. The patients were examined for disease severity by pediatric allergy specialists, and data on history of other allergic diseases, familial allergy history, onset age, trigger factors, lesion sites, treatment history and quality of life were collected. The results of the patient's allergy test were also analyzed. The patients were classified into infancy-onset (< 2 years of age), preschool-onset (2-5 years of age), and childhood-onset (≥ 6 years of age) groups. Study population was analyzed for clinical features according to onset-age groups and severity groups.

RESULTS

A total of 258 patients with a mean age of 10.62 ± 3.18 years were included in the study. Infancy-onset group accounted for about 60% of all patients and presented significantly more other allergic diseases, such as allergic rhinitis and asthma (P = 0.002 and P = 0.001, respectively). Food allergy symptoms and diagnoses were highly relevant to both earlier onset and more severe group. Inhalant allergen sensitization was significantly associated with both infancy-onset group and severe group (P = 0.012 and P = 0.024, respectively). A family history of food allergies was significantly associated with infancy-onset group (P = 0.036). Severe group was significantly associated with a family history of AD, especially a paternal history of AD (P = 0.048 and P = 0.004, respectively). Facial (periorbital, ear, and cheek) lesions, periauricular fissures, hand/foot eczema, and xerosis were associated with infancy-onset group. The earlier the onset of AD, the poorer the quality of life (P = 0.038). Systemic immunosuppressants were used in only 9.6% of the patients in the severe group.

CONCLUSION

This study analyzed the clinical features of AD in Korean children and adolescents through a multicenter nationwide study and demonstrated the phenotypic differences according to onset age and severity. Considering the findings that the early-onset group is more severe and accompanied by more systemic allergic diseases, early management should be emphasized in young children and infants.

Recent Developments and Advances in Atopic Dermatitis: A Focus on Epidemiology, Pathophysiology, and Treatment in the Pediatric Setting

Atopic dermatitis (AD) is a chronic inflammatory skin disorder that affects a substantial number of children and has a significant negative impact on affected patients and their caregivers/families. Recent studies have led to significant evolutions in the understanding of AD pathogenesis, epidemiology, and treatment. The first point of contact for many patients with new-onset AD is usually with their primary care provider or pediatrician. This underscores the importance for pediatricians to understand the basic pathophysiology and current standards of care for AD. This article provides up-to-date information and reviews the basic principles of AD pathophysiology, diagnosis, and management. In addition, the article highlights recent advances in scientific research regarding the mechanisms involved in the pathogenesis of atopic dermatitis that have resulted in the discovery of novel therapeutic targets and the development of targeted biologic therapies with the potential to revolutionize AD therapy.

Prolonged breastfeeding and protective effects against the development of allergic rhinitis: a systematic review and meta-analysis

BACKGROUND

There is insufficient evidence to confirm the protective effects of prolonged breastfeeding against the development of allergic rhinitis (AR).

METHODOLOGY

A systematic review and meta-analysis was performed to assess the associations between prolonged breastfeeding and AR symptoms later in life. Comparisons were conducted between breastfeeding durations less than 6 months and 6 months or more and between less than 12 months and 12 months or more. Exclusive breastfeeding and nonexclusive breastfeeding were analysed separately. Outcomes were risks of AR development later in life.

RESULTS

Twenty-three observational studies (161,611 children, age 2-18 years, 51.50% male) were included. Two studies (9%) were with high quality. Both exclusive and nonexclusive prolonged breastfeeding (6 months or more) decreased the risk of AR. The long-term (12 months or more) nonexclusive breastfeeding lowered the likelihood of AR compared to the 12 months or fewer. The long-term exclusive breastfeeding did not show the same protective effect; however, this result was restricted to only one study.

CONCLUSIONS

Exclusive breastfeeding and nonexclusive breastfeeding for 6 months or more may have protective effects against the development of AR up to 18 years of age. The findings should be interpreted with caution given the limitation of low-quality observational studies.

Risk factors for current wheeze among school children (6–7 and 13–14 years old) in Khuzestan, Iran

Objectives

In recent years, there has been a clear trend of increasing allergic diseases especially in children, and developing countries are no exception. Thepresentstudy sought to determine the risk factors associated with wheezing among school children aged 6–7 and 13–14 years living in Khuzestan Province, Iran.

Study design

Cross-sectional.

Methods

Data for this cross-sectional study is the history of wheeze in the last 12 months. The participants included 6-7- and 13-14-year-old girls and boys studying in urban schools in Khuzestan Province in 2019. We collected the data using the multi stage sampling technique as suggested in the International Study of Asthma and Allergies in Childhood (ISAAC). The research reviewed the literature and consulted experts to collect the risk factors for demographic and clinical information, environmental exposure and lifestyle.

Results

Eight thousand questionnaires were handed out to both age groups, of which 7344 were completed. Two hundred ninety-nine (4.1 %) of the participants had current wheeze. Three-point four percent (124 individuals) in the 6–7 year age group and 4.8 % in the 13–14-year-old age group had current wheezing. The results of the logistic regression model suggest that the most significant risk factors associated with the chance of developing current wheeze in the both age groups are: being male (OR: 1.46, 95 % CI: 1.12–1.88), being from employed mother families (OR: 1.50, 95 %, CI:1.05–2.08), property ownership (OR:1.36, 95 %, CI:1.04–1.79) bugs in the property (OR: 1.29, 95 %, CI:0.99–1.70) mold in the property (OR: 1.75, 95 %, CI:1.12–2.76), pet(s) in the student's bedroom (OR: 1.75, 95 %, CI: 0.97–3.14), a family history of asthma and allergic diseases (OR: 2.20, 95 %, CI: 1.69–2.87), tobacco smoke exposures in the property (OR: 1.43, 95 %, CI:1.04–1.96), having allergic rhinitis (OR: 7.86, 95 % CI: 5.89–10.50) and eczema (OR: 3.85, 95 % CI: 2.10–7.08).

Conclusions

Families are suggested to adopt strategies to reduce exposure to outdoor air pollutants and contain indoor allergens. More studies are necessary to further explore the effects of modifying and changing these risk factors.

•

3.4 % in the 6–7 year age group and 4.8 % in the 13–14 year age group had current wheezing.

•

In both age groups, current wheeze is more common in boys than girls.

•

Mold in the home, pet in the bedroom and tobacco smoke exposures are the most important risk factors for current wheeze.

Type 2 immunity-driven diseases: Towards a multidisciplinary approach

Asthma, atopic dermatitis and chronic rhinoconjunctivitis are highly heterogeneous. However, epidemiologic associations exist between phenotypic groups of patients. Atopic march is one such association but is not the only common point. Indeed, beyond such phenotypes, hallmarks of type 2 immunity have been found in these diseases involving immune dysregulation as well as environmental triggers and epithelial dysfunction. From the canonical Th2 cytokines (IL-4, IL-5, IL-13), new cellular and molecular actors arise, from the epithelium's alarmins to new innate immune cells. Their interactions are now better understood across the different environmental barriers, and slight differences appeared. In parallel, the development of type 2-targeting biotherapies not only raised hope to treat those diseases but also raised new questions regarding their true pathophysiological involvement. Here, we review the place of type 2 immunity in the different phenotypes of asthma, chronic rhinitis, chronic rhinosinusitis and atopic dermatitis, highlighting nuances between them. New hypotheses rising from the use of biotherapies will be discussed along with the uncertainties and unmet needs of this field.

Breastfeeding and risk of childhood asthma: a systematic review and meta-analysis

OBJECTIVE

To investigate the relationship between breastfeeding and the development of paediatric asthma.

METHODS

A systematic review and meta-analysis was conducted with MEDLINE, Embase, CINAHL and ProQuest Nursing and Allied Health source databases. Retrospective/prospective cohorts in children aged <18 years with breastfeeding exposure reported were included. The primary outcome was a diagnosis of asthma by a physician or using a guideline-based criterion. A secondary outcome was asthma severity.

RESULTS

42 studies met inclusion criteria. 37 studies reported the primary outcome of physician-/guideline-diagnosed asthma, and five studies reported effects on asthma severity. Children with longer duration/more breastfeeding compared to shorter duration/less breastfeeding have a lower risk of asthma (OR 0.84, 95% CI 0.75-0.93; I2 = 62.4%). Similarly, a lower risk of asthma was found in children who had more exclusive breastfeeding versus less exclusive breastfeeding (OR 0.81, 95% CI 0.72-0.91; I2=44%). Further stratified analysis of different age groups demonstrated a lower risk of asthma in the 0-2-years age group (OR 0.73, 95% CI 0.63-0.83) and the 3-6-years age group (OR 0.69, 95% CI 0.55-0.87); there was no statistically significant effect on the ≥7-years age group.

CONCLUSION

The findings suggest that the duration and exclusivity of breastfeeding are associated with a lower risk of asthma in children aged <7 years.

Thymic stromal lymphopoietin, skin barrier dysfunction, and the atopic march

OBJECTIVE

Atopic dermatitis often precedes the development of other atopic diseases, and the atopic march describes this temporal relationship in the natural history of these diseases. Although the pathophysiological mechanisms that underlie this relationship are poorly understood, epidemiologic and genetic data have suggested that the skin might be an important route of sensitization to allergens.

DATA SOURCES

Review of recent studies on the role of skin barrier defects in systemic allergen sensitization.

STUDY SELECTIONS

Recent publications on the relationship between skin barrier defects and expression of epithelial cell-derived cytokines.

RESULTS

Animal models have begun to elucidate on how skin barrier defects can lead to systemic allergen sensitization. Emerging data now suggest that epithelial cell-derived cytokines, such as thymic stromal lymphopoietin, drive the progression from atopic dermatitis to asthma and food allergy. Skin barrier defects can lead to induction of epithelial cell-derived cytokines, which in turn leads to the initiation and maintenance of allergic inflammation and the atopic march.

CONCLUSION

Development of new biologic drug targeting type 2 cytokines provides novel therapeutic interventions for atopic dermatitis.

Prevalence and influencing risk factors of eczema among preschool children in Urumqi city: a cross-sectional survey

Background

Eczema is a chronic inflammatory disease associated with impaired quality of life. We identified indoor environmental risk factors, to provide strong evidence for the prevention and control of eczema in preschool children.

Methods

Using a cross-sectional study with stratified random cluster sampling, we conducted a self-administered questionnaire survey among 8153 parents of children aged 2–8 years in 60 kindergartens in six districts of Urumqi city during August 2019.

Results

Among 8153 preschool children, 12.0% of the children have been diagnosed with eczema. Multivariate logistic regression analysis showed that caesarean section (odds ratio [OR] = 1.18, 95% confidence interval [CI]: 1.03–1.36), being an only child (OR = 1.36, 95% CI: 1.18–1.57), presence of mould or moisture in the mother’s home before pregnancy (OR = 1.53, 95% CI: 1.17–2.00), presence of flies or mosquitoes in the dwelling currently (OR = 1.31, 95% CI: 1.10–1.55), pets kept in the child’s home currently (OR = 1.23, 95% CI: 1.01–1.51), presence of pets during child’s first year (OR = 1.45, 95% CI: 1.14–1.85), and family history of eczema (OR = 3.53, 95% CI: 2.98–4.19) are the risk factors for the development of eczema, whereas ethnicity other than the Han Chinese (OR = 0.77, 95% CI: 0.61–0.96) is a protective factor for eczema.

Conclusion

Preschool children in Urumqi are at a high risk of eczema, particularly those of the Han Chinese ethnicity. Parents should be attentive to the indoor living environment of children and take actions to reduce indoor humidity, pest control and elimination, and avoid raising pets to reduce the risk of development of eczema in children.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02819-5.

Phenotypes of atopic dermatitis and the risk for subsequent asthma: a systematic review and meta-analysis

BACKGROUND

Various atopic dermatitis (AD) phenotypes showed an enormously heterogenic risk for subsequent asthma development.

OBJECTIVE

We aimed to investigate the association between AD phenotypes and the risk for progression to asthma.

METHODS

We searched PubMed, Embase, and Web of Science databases for relevant publications. Pooled relative risks (RR) with 95% confidence intervals (CI) were calculated using the CMA-3.0 software. This study has been registered with PROSPERO (CRD42019129273).

RESULTS

We analyzed 39 publications with 458,810 participants. The RR for asthma in AD was 2.16 (95% CI, 1.88-2.48). The risk in persistent AD (RR, 3.36; 95% CI, 2.83-3.99) was higher than in transient AD (RR, 1.52; 95% CI, 1.34-1.73), and in severe AD (RR, 2.40; 95% CI, 1.96-2.94) was higher than mild (RR, 1.82; 95% CI, 1.03-3.23) or moderate (RR, 1.51; 95% CI, 1.30-1.75) AD. The risk for asthma in early-onset AD was slightly higher than in late-onset AD and in boys higher than girls.

LIMITATIONS

The AD and asthma definitions differed across the included studies.

CONCLUSION

Patients with persistent or severe AD were at a higher risk for developing asthma. These findings further elucidate the atopic march and identify target populations for asthma prevention.

Pearls for Managing Atopic Dermatitis in Patients With Low Socioeconomic Status

Atopic dermatitis (AD) is a chronic inflammatory dermatosis presenting with inflamed and itchy skin. Recent studies have shown an inverse relationship between socioeconomic status and the severity of AD. Low socioeconomic status (LSES) individuals with AD face specific barriers that may impede management. These include forgoing doctor's appointments due to transportation costs, inability to take time off from work, and lack of affordable childcare services. Unaffordable medications and over-the-counter products for managing AD further present as significant challenges for LSES patients. This article aims to offer practical and affordable recommendations to help mitigate the challenges faced by LSES patients with AD and thereby alleviate disease burden and improve treatment outcomes.

Association of Childhood Atopic Dermatitis With a Higher Risk of Health Care Utilization and Drug Use for Asthma: A Nationwide Cohort Study

BACKGROUND

Overwhelming evidence supports a causal relationship between occurrence of asthma and atopic dermatitis (AD).

OBJECTIVE

The aims of the study were to determine the incidence of asthma in children with AD and to examine the health care utilization and drug use for asthma in children with AD.

METHODS

Children with hospital-diagnosed AD (cases) were matched with individuals from the background population (controls) in a 1:4 ratio.

RESULTS

In the final cohort (18,625 cases and 74,500 controls), the incident cases of asthma were 4203 among AD cases and 5298 in controls, corresponding to incidence rates of 34 and 9 in cases and controls per 1000 person-years, respectively (hazard ratio [HR] = 3.82, 95% confidence interval [CI] = 3.65-4.00). During the 1-year follow-up period from asthma diagnosis, children with concomitant AD had a significantly higher risk of hospital admission (HR = 1.97, 95% CI = 1.63-2.37), emergency department visits (HR = 1.62, 95% CI = 1.22-2.14), outpatient visits (HR = 1.97, 95% CI = 1.74-2.23), asthma medication (HR = 1.31, 95% CI = 1.27-1.35), and rescue course corticosteroids (HR = 1.74, 95% CI = 1.13-2.69) compared with children with asthma only.

CONCLUSIONS

The risk of being diagnosed with asthma was higher in children with AD. Risk of health care utilization and drug use for asthma was higher in children with both AD and asthma compared with asthma only.

Increased all-cause mortality in concomitant atopic dermatitis and asthma: A nationwide registry-based study

BACKGROUND

Excess mortality has been reported for adults with atopic dermatitis (AD) and asthma.

OBJECTIVE

To assess the mortality rate in adults with concomitant AD and asthma.

METHODS

Adults with hospital-diagnosed AD were matched (1:4) with non-AD individuals from the background population.

RESULTS

The study cohort comprised 8,095 adults with AD (of which 1,201 (14.8%) had concomitant asthma) and 32,380 reference individuals without AD from the background population (of which 878 (2.7%) had asthma). A total of 1,057, 330, 55 and 99 deaths were observed among subjects with neither AD nor asthma, AD only, asthma only, and subjects with concomitant AD and asthma, respectively. The mortality rate per 1,000 person-years was 4.75 (95% CI 4.47-5.05) for subjects with neither AD nor asthma, 7.17 (95% CI 5.92-10.05) for asthma only, 7.09 (95% CI 6.37-7.90) for AD only and 10.87 (95% CI 8.92-13.23) for concomitant AD and asthma. Risk for all-cause mortality was increased in subjects with concomitant AD and asthma compared to asthma only (HR 1.52, 95% CI 1.07-2.15) and neither AD nor asthma (HR 2.27, 95% CI 1.83-2.81) but not compared to subjects with AD only (HR 1.10, 95% CI 0.87-1.39). However, compared to AD only subjects with AD and asthma had increased risk of death due to pulmonary disease (HR 1.81, 95% CI 1.04-3.15).

CONCLUSION

Adults with AD, asthma or both conditions have increased risk of death, and further concomitant AD and asthma have increased risk of death compared with asthma alone.

Associations between maternal and environmental exposures on atopic disease in the offspring of mothers with asthma

Background and Objective

Available data on the impact of perinatal and environmental factors on atopic diseases in the offspring are sparse and conflicting. We, therefore, investigated the impact of these factors on the risk of atopic diseases in the offspring of women with asthma.

Methods

Pregnant women referred to give birth at Copenhagen University Hospital‐Hvidovre, Denmark, have since 2007 been invited to participate in the Management of Asthma during Pregnancy program. Women with diagnosed asthma, currently prescribed asthma medication, first visit to the respiratory out‐patient clinic within the first 18 weeks of pregnancy that completed an online questionnaire about atopic diseases in their child were included in the current study.

Results

Five hundred and seventy‐one pregnancies were included. Among the off‐spring, 113 children (21%) had doctor‐diagnosed asthma, 178 (31%) atopic dermatitis (AD), and 55 (32%) both AD and doctor‐diagnosed asthma. AD in the offspring was associated with having a dog at home (odds ratio [OR], 2.56; 95% confidence interval [CI], [1.40–4.67], p = .002), whereas having a cat at home was associated with a higher risk of asthma in the offspring (OR, 2.16; 95% CI, [1.14–4.11], p = .02). The associations remained significant after adjusting for maternal age, smoking status, allergy, treatment with inhaled corticosteroids, forced expiratory volume in 1 s less than 80% predicted, uncontrolled asthma, and history of pre‐pregnancy asthma exacerbations. No association was found between gestational weight gain (GWG) in first trimester and total GWG and atopic disease in the offspring.

Conclusion

Having pets at home is associated with AD and asthma in the offspring of mothers with asthma.

Factors Associated With Postadenotonsillectomy Unexpected Admissions in Children

BACKGROUND

Postadenotonsillectomy unexpected admission remains an important challenge. Unexpected admissions can be quite frightening, increase health care burden, and cause unnecessary suffering in children and families. Identifying factors associated with postadenotonsillectomy unexpected admissions using a pragmatic approach could lead to a shift in the assessment and management of children presenting for adenotonsillectomy.

METHODS

Institutional review board (IRB) approval, consent, and assent were obtained for this single-center, prospective, observational study done in children aged 0-17 years undergoing tonsillectomy. Data were collected from direct observation, electronic medical record, and phone calls using Research Electronic Data Capture (REDCap) database. Incidence, causes, and factors associated with 3-week and 3-day postadenotonsillectomy unexpected admissions were analyzed.

RESULTS

The study included 2375 children. Clinical intraoperative adverse events were reported in 6.2%. Three-week and 3-day unexpected admissions occurred in 7.9% and 5.9%, respectively, with bleeding being the commonest reason for both. On multivariable analysis, for 3-week unexpected admissions, the odds ratio was 2.3 (95% confidence interval, 1.44-3.76) with using preoperative medications, 1.4 (1.02-1.97) with home medications for comorbidities, 0.56 (0.34-0.90) with using intraoperative acetaminophen, and 0.60 (0.36-0.94) with otolaryngologic preoperative comorbidity versus otherwise. For 3-day unexpected admissions, the odds ratio was 1.10 (1.05-1.16) with 1 U increase in total comorbidities, 1.70 (1.03-2.81) with the presence of recent upper respiratory infection, and 1.83 (1.16-2.90) with intravenous versus inhalational anesthesia induction.

CONCLUSIONS

Overall, our study shows the factors that contribute to unexpected admissions postadenotonsillectomy. Identification of both modifiable and nonmodifiable factors associated with unexpected admissions after adenotonsillectomy will enable appropriate risk mitigation.

Impact of Snoring on Telomere Shortening in Adolescents with Atopic Diseases

Atopic diseases can impose a significant burden on children and adolescents. Telomere length is a cellular marker of aging reflecting the impact of cumulative stress exposure on individual health. Since elevated oxidative stress and inflammation burden induced by chronic atopy and snoring may impact telomere length, this study aimed to investigate whether snoring would moderate the relationship between atopic diseases and telomere length in early adolescence. We surveyed 354 adolescents and their parents. Parents reported the adolescents' history of atopic diseases, recent snoring history as well as other family sociodemographic characteristics. Buccal swab samples were also collected from the adolescents for telomere length determination. Independent and combined effects of atopic diseases and snoring on telomere length were examined. Among the surveyed adolescents, 174 were reported by parents to have atopic diseases (20 had asthma, 145 had allergic rhinitis, 53 had eczema, and 25 had food allergy). Shorter TL was found in participants with a history of snoring and atopic diseases (β = -0.34, p = 0.002) particularly for asthma (β = -0.21, p = 0.007) and allergic rhinitis (β = -0.22, p = 0.023). Our findings suggest that snoring in atopic patients has important implications for accelerated telomere shortening. Proper management of atopic symptoms at an early age is important for the alleviation of long-term health consequences at the cellular level.

Mapping risk factors for cumulative life course impairment in patients with chronic skin diseases - a systematic review

Patients with chronic skin diseases suffer from physical and psychosocial impairments which can lead to a cumulative life-long burden. Therefore, the concept of cumulative life course impairment (CLCI) was introduced, referring to the non-reversible damage due to the persistent life-long burden. This systematic review (PROSPERO registry number: CRD42020179141) aimed at mapping the risk factors and the associated burden over time in patients with psoriasis, atopic dermatitis (AD) and hidradenitis suppurativa (HS). Three electronic databases were searched (date of the last search: December 2019). Studies with a longitudinal study design that assessed the association between a risk factor and the associated burden over time in patients with psoriasis, AD and HS were included. Quality assessment of the included studies was done using Critical Appraisal Skills Programme (CASP) checklists. In total, 40 publications reflecting 25 different studies were included: nine studies addressed patients with psoriasis, 13 patients with AD, two studies included patients with HS and one study enrolled patients with psoriasis and AD, respectively. Twenty-two potential risk factors with underlying evidence were found in this review. These risk factors include mainly sociodemographic (such as age or gender) and clinical (such as disease severity or comorbidities) variables. Disease severity and comorbidities were the most often studied risk factors, while only a few studies evaluated psychosocial risk factors over time. Patients with chronic skin diseases are at high risk to develop a life-long negative impact from the disease. However, there is a lack of data that evaluates the psychosocial burden and its influence on the patients' life course over time. The risk factors found in this review help to identify patients at risk, to treat them adequately and, ultimately, to prevent CLCI. These results can be the basis to develop a highly needed tool to assess the risk for CLCI in the future.

A population-based study on associations of stool microbiota with atopic diseases in school-age children

BACKGROUND

Infants with less diverse gut microbiota seem to have higher risks of atopic diseases in early life, but any associations at school age are unclear.

OBJECTIVES

This study sought to examine the associations of diversity, relative abundance, and functional pathways of stool microbiota with atopic diseases in school-age children.

METHODS

We performed a cross-sectional study within an existing population-based prospective cohort among 1440 children 10 years of age. On stool samples, 16S ribosomal RNA gene sequencing was performed, and taxonomic and functional tables were produced. Physician-diagnosed eczema, allergy, and asthma were measured by questionnaires, allergic sensitization by skin prick tests, and lung function by spirometry.

RESULTS

The α-diversity of stool microbiota was associated with a decreased risk of eczema (odds ratio [OR], 0.98; 95% CI, 0.97, 1.00), and β-diversity was associated with physician-diagnosed inhalant allergy (R² = 0.001; P = .047). Lachnospiraceae, Ruminococcaceae_UCG-005, and Christensenellaceae_R-7_group species were associated with decreased risks of eczema, inhalant allergic sensitization, and physician-diagnosed inhalant allergy (OR range, 0.88-0.94; 95% CI range, 0.79-0.96 to 0.88-0.98), while Agathobacter species were associated with an increased risk of physician-diagnosed inhalant allergy (OR, 1.23; 95% CI, 1.08-1.42). Functional pathways related to heme and terpenoid biosynthesis were associated with decreased risks of physician-diagnosed inhalant allergy and asthma (OR range, 0.89-0.86; 95% CI range, 0.80-0.99 to 0.73-1.02). No associations of stool microbiota with lung function were observed.

CONCLUSIONS

The diversity, relative abundance and functional pathways of stool microbiota were most consistently associated with physician-diagnosed inhalant allergy in school-age children and less consistently with other atopic diseases.

Clinical and Economic Burden of Mild-to-Moderate Atopic Dermatitis in the UK: A Propensity-Score-Matched Case-Control Study

Introduction

The burden of mild-to-moderate atopic dermatitis (AD) in the United Kingdom (UK) is not well understood. Long-lasting AD flares may lead to systemic inflammation resulting in reversible progression from mild to more severe AD. This study aimed to assess the clinical and economic burden of mild-to-moderate AD in the UK.

Methods

AD patients were identified in the Health Improvement Network (THIN) from 2013 to 2017 and propensity score matched to non-AD controls by demographics. Patients were identified based on continuous disease activity using validated algorithms and sufficient patient status to fully validate data integrity for the entire period. Mild-to-moderate AD patients were identified by using treatment as a surrogate. Demographics, clinical characteristics and healthcare resource use (HCRU) were obtained from THIN. Literature reviews were conducted to obtain additional outcomes. A cost-of-illness model was developed to extrapolate the burden in 2017 to the UK population and in subsequent years (2018–2022).

Results

In 2017, the prevalence of mild-to-moderate AD in THIN was 1.28%. These patients reported higher comorbidity rates and significantly higher (p < 0.0001) HCRU, encompassing mean general practitioner visits (5.57 versus 3.59), AD-related prescriptions (5.85 versus 0.68) and total referrals (0.97 versus 0.82) versus matched non-AD controls. The model projected total HCRU and drug excess costs of €462.99M over the 5 years. The excess cost decreased to €417.35M after excluding patients on very potent topical corticosteroids, who most likely had at least moderate disease. The excess costs increased to €1.21B and €7.06B when considering comorbidity burden and productivity losses, respectively.

Conclusion

Mild-to-moderate AD patients had higher comorbidity burden, HCRU and cost compared with matched non-AD controls. Overall, UK country-based economic burden was high given partly the high prevalence of this disease. Moreover, productivity burden and comorbidities had considerable impact on the economic burden, which further suggests the importance of optimal disease management.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13555-021-00519-7.

Rhinitis prevalence and association with atopic dermatitis: A systematic review and meta-analysis

BACKGROUND

Atopic dermatitis (AD) and rhinitis are common atopic diseases that may co-occur owing to an overlap in pathophysiology. Although most cases of both diseases are mild and managed with topical anti-inflammatory medicaments, the advent of new systemic and biologic treatments targeting type 2 inflammation in both diseases warrants further insight in the exact overlap of AD and rhinitis.

OBJECTIVE

To determine the association between AD and rhinitis.

METHODS

A systematic review and meta-analysis of the databases PubMed, Embase, and CNKI were performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Pooled prevalence and pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated.

RESULTS

The search resulted in 10,422 citations, and 341 and 302 articles were included in the qualitative and quantitative analyses, respectively. The pooled prevalence of rhinitis was 40.5% (95% CI 39.0-42.0) in patients with AD and 18.0% (95% CI 16.7-19.2) in the reference individuals without AD. The pooled prevalence of having both rhinitis and asthma was 14.2% (95% CI 13.0-15.5) in patients with AD. There was an association between AD and rhinitis (OR 3.00, 95% CI 2.83-3.18), allergic rhinitis (OR 3.25, 95% CI 2.26-4.66), and nonallergic rhinitis (OR 1.99, 95% CI 1.39-2.86), respectively.

CONCLUSION

Rhinitis, both allergic and nonallergic forms, is very common in patients with AD. Future investigations should clarify how medications targeting both diseases should be indicated in these patients.

Question 6: What is the use of allergy testing in children with asthma?

Disagreement exists between asthma guidelines on the routine use of allergy testing in the diagnostic work-up of a child with persistent asthma, although the important role of inhalant allergy in the pathophysiology of asthma and allergic rhinitis is undisputed. The usefulness of screening for inhalant allergies in asthma is connected to the efficacy of allergen reduction measures and specific immunotherapy, both of which appear to be more effective in children than in adults. Allergen-specific exposure reduction recommendations are therefore an essential part of childhood asthma management. Such recommendations should be guided by appropriate diagnosis of inhalant allergy, based on a structured allergy history and results of sensitization tests. Specific IgE testing and skin prick testing show comparable results in identifying clinically important sensitizations. Although a therapeutic medication trial can be started pragmatically in children with asthma without diagnosing their inhalant allergy, we recommend making or excluding an accurate diagnosis of inhalant allergy.