Allergy and immunology in young children of Japan: The JECS cohort

Surveys on the prevalence of pediatric asthma in Japan: A comparison between the 1982, 1992, 2002, 2012, and 2022 surveys conducted in the same region using the same methodology (WJSAAC PhaseⅠ∼Ⅴ)

Objectives

To investigate the trends in the prevalence of pediatric asthma in the western part of Japan over 40 years, using data from surveys conducted every 10 years from 1982 to 2022.

Design

A series of school-based epidemiological surveys conducted every 10 years.

Setting

Elementary schools in 11 prefectures in the western part of Japan.

Participants

Children aged 6-12 years. Surveys included 55,388 children in 1982, 46,718 in 1992, 36,228 in 2002, 33,902 in 2012, and 30,024 in 2022.

Main outcome measures

Prevalence of asthma, wheeze, and other allergic diseases such as allergic rhinitis, atopic dermatitis, and food allergies.

Results

The prevalence of asthma increased from 1982 to 2002 (boys: 3.8%-8.1%; girls: 2.5%-5.0%) and then decreased in 2012 and 2022 (boys: 6.0%-3.2%; girls: 3.5%-2.1%). The prevalence of wheeze followed a similar trend. Allergic rhinitis was the most common comorbidity, affecting 53-58% of children from 1992 onwards. Other comorbidities included atopic dermatitis, allergic conjunctivitis, and pollinosis. The prevalence of asthma was higher in urban areas than in rural areas in the early surveys, but this difference disappeared in later surveys.

Conclusions

The prevalence of pediatric asthma in western Japan increased until 2002 and then decreased in subsequent surveys. Changes in environmental factors and public health measures, including those related to the COVID-19 pandemic, may have influenced these trends. Further research is needed to understand the long-term effects of these factors on asthma prevalence.

Association Between Maternal Dietary Isoflavone Intake During Pregnancy and Childhood Allergic Rhinoconjunctivitis: The Japan Environment and Children's Study

Background/Objectives: Isoflavone (ISO) may have immunosuppressive and promoting effects. In this study, we aimed to examine the association between maternal dietary ISO intake during pregnancy and childhood allergic rhinoconjunctivitis at the age of 3 years using the Japanese Birth Cohort data. Methods: Overall, 78,549 mother-child pairs were studied. Maternal dietary ISO intake (the sum of genistein and daidzein) during pregnancy was evaluated using a food frequency questionnaire. Information on physician-diagnosed allergic rhinoconjunctivitis was collected from the caregiver-reported questionnaire. After classifying ISO intake into quartiles (Q1: reference), multivariable logistic regression analysis was employed to explore the association with allergic rhinoconjunctivitis. Results: No association was observed between maternal ISO intake and allergic rhinoconjunctivitis in any child. However, in the sex-stratified analysis, maternal ISO intake linked to allergic rhinoconjunctivitis in female children positively (Q2, adjusted odds ratio [aOR]: 1.22, 95% confidence interval [CI]: 1.06-1.40; Q3, aOR: 1.17, 95% CI: 1.01-1.35; Q4, aOR: 1.24, 95% CI: 1.07-1.44). Conclusions: Maternal dietary ISO intake during pregnancy was sex-specifically linked to childhood allergic rhinoconjunctivitis in children. These findings provide insights into the need for estimating the optimal ISO consumption during pregnancy for allergy avoidance in children.

English version of clinical practice guidelines for the management of atopic dermatitis 2024

This is the English version of the 2024 clinical practice guidelines for the management of atopic dermatitis (AD). AD is a disease characterized by relapsing eczema with pruritus as a primary lesion. A crucial aspect of AD treatment is the prompt induction of remission via the suppression of existing skin inflammation and pruritus. To achieve this, topical anti-inflammatory drugs, such as topical corticosteroids, tacrolimus ointment, delgocitinib ointment, and difamilast ointment, have been used. However, the following treatments should be considered in addition to topical therapy for patients with refractory moderate-to-severe AD: oral cyclosporine, subcutaneous injections of biologics (dupilumab, nemolizumab, tralokinumab), oral Janus kinase inhibitors (baricitinib, upadacitinib, abrocitinib), and phototherapy. In these revised guidelines, descriptions of five new drugs, namely, difamilast, nemolizumab, tralokinumab, upadacitinib, and abrocitinib, have been added. The guidelines present recommendations to review clinical research articles, evaluate the balance between the advantages and disadvantages of medical activities, and optimize medical activity-related patient outcomes with respect to several important points requiring decision-making in clinical practice.

Relationship between maternal egg consumption during lactation and the risk of developing egg allergies in 12-month-old infants: A multicenter cohort study

AIM

To determine the effect of maternal egg consumption during lactation on the development of egg allergies in 12-month-old infants. We hypothesized that infants whose mothers consume larger amounts of eggs during the early lactation period acquire oral immune tolerance and are less likely to develop egg allergies at 12 months.

METHODS

This study was a part of the Japan Pregnancy Eating and Activity Cohort Study. Mothers answered questionnaires on egg consumption, breastfeeding rates at 1 month, infants' eczema at 6 months, and the development of egg allergies among infants at 12 months. In order to assess the actual impact of maternal egg consumption on infants' egg allergy development, breastfeeding-dependent egg consumption was calculated at 1 month by multiplying maternal egg consumption at 1 month with the breastfeeding rates at the same time. Logistic regression analysis was performed to examine the potential risk and protective factors.

RESULTS

Data from 420 infants were analyzed, of whom 27 had egg allergies at 12 months. No significant impact of breastfeeding-dependent egg consumption was observed on infants' egg allergy development at 12 months. However, infants with eczema at 6 months showed a greater risk of developing an egg allergy at 12 months (adjusted odds ratio, 3.59; 95% confidence interval, 1.59-8.13).

CONCLUSION

The results suggest that breastfeeding-dependent egg consumption at 1 month did not contribute to sufficient oral immune tolerance in 12-month-old infants. Eczema at 6 months significantly impacted the development of an egg allergy, emphasizing the importance of preventing cutaneous exposure to egg allergens.

Japanese version of the food allergy quality of life questionnaire 10: An easy-to-use instrument

Background

The health-related quality of life (HRQL) of people with food allergies should be evaluated to provide high-quality medical care. Currently, there is no available easy-to-use and reliable instrument for assessing HRQL clinically in Japan.

Methods

The Food Allergy Quality of Life Questionnaire 10 (FAQLQ10) in English was translated into Japanese, and this was referred to as the Japanese version of the Food Allergy Quality of Life Questionnaire 10 (FAQLQ10-J). Participants aged up to 18 years, who had food allergy, and their parents were instructed to complete the FAQLQ10-J and the Food Allergy Independent Measure, a self-report instrument. For comparison, participants without food allergies were also included in the survey.

Results

The FAQLQ10-J, which included forms for individuals aged 8-12 years, teenagers, and caregivers was developed. The responders completed each form within approximately 3 min. An analysis of responses showed that each form had a good internal consistency, test-retest reliability, construct validity, and discriminant validity. Moreover, based on an examination of the relationship between demographic data and FAQLQ10-J scores, items such as possession of an adrenaline auto-injector, participant age, and number of eliminated foods might influence HRQL.

Conclusions

We developed the FAQLQ10-J, which is a simple, reliable, and effective tool for assessing HRQL among Japanese individuals with food allergy. Its use may provide a more detailed understanding of HRQL among individuals with food allergy in clinical settings and may facilitate the development of more individual-oriented treatments.

Skin and oral intervention for food allergy prevention based on dual allergen exposure hypothesis

Early-onset atopic dermatitis increases an individual's risk of food allergies, suggesting that transcutaneous sensitization may occur through inflamed skin. Regarding food allergy causation, the dual allergen exposure hypothesis proposes that oral allergen exposure leads to immune tolerance, whereas allergen exposure via inflamed skin causes food allergies. This hypothesis suggests that it is important to induce oral immune tolerance and prevent allergic food sensitization through the skin. This review focuses on the breakthrough evidence based on the dual allergen exposure hypothesis that involves both skin and oral interventions for food allergy prevention.

Management of Infant Atopic Eczema to Prevent Severe Eczema and Food Allergy

Early intervention and active management of infant atopic eczema may play a crucial role in limiting eczema severity and preventing the onset of immediate-type food allergy. Eczema management involves education, skincare and medications targeting skin inflammation and barrier repair. Topical corticosteroids are the mainstay of anti-inflammatory therapy, with nonsteroidal options available for some infants. Proactive therapy, addressing subclinical inflammation, is useful for preventing eczema flares, especially in infants with recurrent eczema flares despite reactive therapy. In clinical practice, holistic consideration of overall infant and family health is essential. Providing advice on maternal stress management, nutritional guidance and recommendations for proper sleep and lifestyle is crucial for the well-being of children and their families, not limited to eczema treatment alone.

Levilactobacillus brevis IBARAKI-TS3 Isolated From Pickles Promotes Production of Interleukin-10 via Toll-Like Receptor 2 in Human M2 Macrophages

M2 macrophages play an important role in food allergy. Several studies have reported that lactic acid bacteria isolated from pickles exert antiallergic effects. We investigated the effects of several strains of lactic acid bacteria on the immune function of M2 macrophages. M2 macrophages differentiated from THP-1 cell line by interleukin-4 (IL-4) and IL-13 strongly expressed CD163, CD206, and HMOX1 mRNA. Levilactobacillus brevis IBARAKI-TS3 (IBARAKI-TS3) isolated from pickles was identified as a lactic acid bacterium that enhances the expressions of IL-10 and EBI3 mRNA in M2 macrophages. IBARAKI-TS3 induced the expression of genes involved in Toll-like receptor (TLR) signaling, such as IRAK, mitogen-activated protein kinases (MAPKs), and NF-κB mRNA. IBARAKI-TS3-induced IL-10 production was suppressed by anti-TLR2-neutralizing antibodies. Furthermore, the IBARAKI-TS3-induced increase in IL-10 levels was significantly reduced in TLR2-knockdown M2 macrophages compared to M2 macrophages. These results suggest that IBARAKI-TS3 promotes of IL-10 production via TLR2 in M2 macrophages.

Using a survey, analyzing the current situation of allergic March in elementary and junior high school students of oyama and tochigi cities, Japan

BACKGROUND

Over the past few decades, allergic diseases have become more prevalent and impact around 20% of the global population. There is clinical significance of allergic march as it places a burden on the quality of life of children and their families.

OBJECTIVES

To assess the current situation of allergy conditions experienced by children attending elementary and junior high schools in Oyama and Tochigi cities, Japan.

METHODS

A letter was sent to parents informing them about an opt-in online survey concerning children's allergies along with a weblink and a QR code. A video explained the survey process and informed parents that their replies could not be retracted. Parents who had watched the explanation video and answered yes to participating were considered to have provided consent for the survey.

RESULTS

A total of 2038 valid replies were gathered. Allergic Rhinitis was the most commonly diagnosed allergy, followed by Asthma, Food Allergy, and Atopic Dermatitis. Around 70% of the children were affected by the allergies, of whom half had been affected by multiple allergies. Most children affected by Atopic Dermatitis, Food Allergy or Asthma were affected by other allergies. Atopic Dermatitis and Food Allergy were mostly diagnosed before Asthma and Allergic Rhinitis.

CONCLUSIONS

Children who are diagnosed with either Atopic Dermatitis or a Food Allergy will likely be affected by other allergies later in life. Allergic march perpetuated an earlier peak diagnosis incident rate for allergic rhinitis. Allergic Rhinitis can occur independently from other allergies compared to Atopic Dermatitis, Food Allergy and Asthma.

Food allergy in a changing dietary landscape: A focus on the Asia Pacific region

Recent studies have provided compelling evidence to suggest that various environmental factors play a significant role in the development of food allergies. As our society experiences rapid economic growth, increased urbanization, and a shift towards a more Westernized diet, the incidence of food allergies is also on the rise and the pattern is gradually evolving. This review will delve into the changes in the epidemiology of food allergies within the Asia-Pacific region and the various dietary practices and factors that are postulated to play a role in the rise in food allergies over the years. Although there have been important advancements in the field of food allergies, there are still numerous uncertainties regarding the intricate relationship between diet and food allergies. Specifically, the role of epigenetic factors in influencing the susceptibility to food allergies, as evidenced by studies that assessed the impact of migration and rural-urban dynamics, is not fully understood. Addressing this knowledge gap presents an opportunity to develop more effective prevention and treatment strategies that could greatly benefit individuals living with food allergies.

Influence of household pet ownership and filaggrin loss-of-function mutations on eczema prevalence in children: A birth cohort study

BACKGROUND

The association between pet exposure in infancy, early childhood eczema, and FLG mutations remains unclear.

METHODS

This was a birth cohort study performed in Tokyo, Japan. The primary outcome was current eczema based on questionnaire responses collected repeatedly from birth to 5 years of age. Generalized estimating equations and generalized linear modeling were used to evaluate the association.

RESULTS

Data from 1448 participants were used for analyses. Household dog ownership during gestation, early infancy, and 18 months of age significantly reduced the risk of current eczema. Household cat ownership also reduced the risk of current eczema, albeit without statistical significance. The combined evaluation of children from households with pets, be it cats, dogs or both, the risk of current eczema at 1-5 years of age was lower in those with household pet exposure ownership during gestation (RR = 0.59, 95 % CI 0.45-0.77) and at 6 months (RR = 0.49, 95 % CI 0.36-0.68). , Reduced risks of eczema were also observed at 2-5 (RR = 0.52, 95 % CI 0.37-0.73) and 3-5 years of age (RR = 0.50 95 % CI 0.35-0.74) when the respective household pet ownership were evaluated at 18 months and 3 years of age. These protective associations of reduced risk of eczema were only observed in children without FLG mutations.

CONCLUSIONS

Household dog and pet (dog, cat, or both) ownership was protective against early childhood eczema in a birth cohort dataset. This protective association was observed only in children without FLG mutations, which should be confirmed in studies with larger cohorts.

Parental stress and food allergy phenotypes in young children: A National Birth Cohort (JECS)

BACKGROUND

Food allergy children and their families tend to have emotional distress and anxiety. There have been few reports of differences in parenting stress and a child's food allergy phenotypes.

METHODS

We examined the associations between food allergy phenotypes in children and parenting stress assessed by the Parenting Stress Index-Short Form (PSI-SF) from a national birth cohort (Japan Environment and Children's Study).

RESULTS

We included 65,805 children for statistical analysis. Of them, 7.2% of children had a food allergy diagnosis at 2 years old. The means of the total PSI-SF (39.9 ± 10.3, 39.1 ± 9.9), CD-SF (19.5 ± 5.4, 19.1 ± 5.2), and PD-SF (20.5 ± 6.3, 20.0 ± 6.1) scores are similar for caregivers in the with and without food allergy groups. Food allergy diagnosis resulted in significantly higher total PSI scores (coefficient .47, 95% CI 0.19-0.75, p = .001), CD-SF (coefficient .22, 95% CI 0.07-0.38, p = .004), and PD-SF (coefficient .24, 95% CI 0.08-0.41, p = .004). A similar trend was observed for allergy reactions to hen's egg. However, there was no clear relationship between allergic reactions to milk, wheat, nuts, and PSI-SF.

CONCLUSIONS

Parental stress was significantly related to a child's food allergy. Furthermore, hen's egg allergy increased parental stress. Multiple food avoidance might also increase parental stress. Healthcare providers need to be aware of parental stress in our daily clinic.

Predictive modeling for cow's milk allergy remission by low-dose oral immunotherapy in young children

Background

The effectiveness of slow low-dose oral immunotherapy (SLOIT) for cow's milk (CM) allergy has been reported. Most OIT studies have discussed the target populations over 4 years old. Furthermore, no predicting modeling is reported for CM allergy remission by CM-SLOIT under 4 years of age.

Objective

We sought to develop a predictive model for CM allergy remission by SLOIT after 3 years in young children who started CM-SLOIT under 4 years of age.

Methods

We included young children with cow's milk allergy or cow's milk sensitization (development modeling set with 120 children and validation modeling set with 71 children). We did logistic regression analysis to develop the models. We calculated the area under the receiver operating curves (ROC-AUCs) to evaluate the predictive modeling performance.

Results

The model (CM-sIgE before SLOIT + age at beginning SLOIT + serum TARC before starting SLOIT + CM-sIgE titer one year after OIT) showed good discrimination with the ROC-AUC of 0.83 (95% CI:0.76-0.91) on internal validation. Applying the model to the validation set gave good discrimination (ROC-AUC = 0.89, 95% CI:0.80-0.97) and a reasonable calibration (intraclass correlation coefficient = 0.88, 95% CI:0.62-0.97).

Conclusion

We developed and validated predictive modeling for determining the remission rate of CM allergy at 3 years after SLOIT under 4 years of age in children with CM allergy. This predictive model is highly accurate and can support CM allergy management. (226 words).

Association of allergies in children younger than 3 years with levels of maternal intake of n-3 polyunsaturated fatty acids or fish during pregnancy: A nationwide birth cohort study, the Japan Environment and Children's Study

BACKGROUND

N-3 polyunsaturated fatty acids (PUFAs) have anti-inflammatory properties and are expected to prevent the onset of allergies. However, epidemiological studies investigating the relationship between child allergies and maternal intake of n-3 PUFAs or fish have yielded inconsistent results.

METHODS

Following exclusions from a dataset comprising 103,057 records from the Japan Environment and Children's Study, 72,105 participants were divided into five groups according to mothers' intake of n-3 PUFAs or fish during pregnancy to assess the risk of their children being diagnosed with allergy by 3 years old. Adjusted odds ratios (aORs) with 95% confidence intervals (CIs) for child allergies were calculated using multivariable logistic regression analyses with reference to the lowest intake group.

RESULTS

Levels of maternal intake of n-3 PUFAs or fish showed inverted associations (i.e., reduced risk) with the incidence of physician-diagnosed allergic rhinoconjunctivitis or parent-reported symptoms of current rhinitis with eye symptoms at different time points and the cumulative incidence from birth to 3 years of age. Inverted associations were also found for current wheeze at 1-<2 years of age and current eczema at 1-<2 and 0-<3 years of age. However, for food allergies, no significant associations were observed in the incidence in each group compared with the lowest intake group at any age.

CONCLUSIONS

The findings suggest that n-3 PUFA intake during pregnancy may reduce the risk of developing allergic diseases and symptoms in children. In addition, consumption of n-3 PUFAs or fish is very unlikely to increase the risk of allergy given that the results are from a country with high fish consumption.

TRIAL REGISTRATION

UMIN000030786 https://rctportal.niph.go.jp/detail/um?trial_id=UMIN000030786.

Early childhood neurodevelopmental milestones in children with allergic diseases: the Japan Environment and Children's Study (JECS)

This study investigated the potential link between early childhood allergic diseases and neurodevelopmental milestone attainment during the first 3 years of life. Utilizing data from a large-scale prospective birth cohort study in Japan, encompassing 87,986 children, we examined physician-diagnosed and caregiver-reported allergic conditions, including atopic dermatitis (AD), asthma, and food allergy (FA). Neurodevelopmental milestones were assessed using the Ages and Stages Questionnaires at 1, 1.5, 2, 2.5, and 3 years of age. Stabilized inverse probability-weighted generalized estimating equation models were employed to estimate odds ratios (ORs). Our analysis revealed no significant association of AD and asthma with delay in communication, gross motor, fine motor, problem-solving, and personal-social skills during the initial 3 years of life. However, children with FA showed an increased likelihood of experiencing gross motor delay compared with that shown by those without FA (weighted adjusted OR: 1.14). Despite this, no significant association of FA with other developmental domains was observed. Early childhood allergies may not influence neurodevelopmental delays. However, there is a potential association between FA and delays, specifically in gross motor skills, that warrants routine developmental monitoring and additional investigations.

Epidemiology and the Growing Epidemic of Food Allergy in Children and Adults Across the Globe

PURPOSE OF REVIEW

Food allergies are immune-mediated, complex disorders, which are the source of increasing health concern worldwide. The goal of this review is to present an updated summary of the food allergy (FA) burden among children and adults across different populations, focusing on research from the past 5 years.

RECENT FINDINGS

FAs impact a growing number of global residents-particularly those residing in higher-income, industrialized regions. Moreover, growing epidemiologic evidence suggests that the population health burden of non-IgE-mediated FAs, such as food protein-induced enterocolitis syndrome, may also be higher than previously reported. FA is a complex trait that impacts infants, children, as well as adults across the globe. The population health burden of both IgE- and non-IgE-mediated FAs is likely to grow in the absence of rapid advances and widespread implementation of effective FA prevention and treatment interventions. Systematic epidemiological research initiatives are needed, both nationally and globally, to better understand and reduce the burden of these allergic diseases.

Discrepancy between Caregivers' Reports and Physicians' Evaluation of Causative Foods in Food Protein-Induced Enterocolitis Syndrome in Japan: The Japan Environment and Children's Study

INTRODUCTION

Food protein-induced enterocolitis syndrome (FPIES) is a form of non-IgE-mediated gastrointestinal food allergy. FPIES is considered a rare food allergy disorder and is often under-recognized. Therefore, clinicians should have a better understanding of its manifestations and maintain a high index of suspicion for a correct diagnosis. To this end, information about differences in the characteristics of caregiver-reported and physician-diagnosed FPIES is important.

METHODS

The present, national, multicentric, prospective birth cohort study, called the Japan Environment and Children's Study (JECS), enrolled a general population of 104,062 fetal records. The characteristics of FPIES in 1.5-year-old children were categorized as cases reported by caregivers or as those diagnosed by a physician using questionnaire data.

RESULTS

The prevalence of caregiver-reported and physician-diagnosed FPIES cases was 0.69% and 0.06%, respectively. Among the former, the most common causative food was hen's egg (HE), and the second most common causative food was cow's milk (CM) (51.0% and 17.1% of patients responded to HE and CM, which accounted for 46% and 15% of all the causative foods, respectively). Conversely, among the physician-diagnosed cases, the most common causative food was CM followed by HE (57.7% and 36.5% of patients responded to CM and HE, which accounted for 46% and 29% of all the causative foods, respectively). CM accounted for a significantly higher proportion of causative foods in physician-diagnosed FPIES while HE accounted for a significantly higher proportion of caregiver-reported FPIES (p < 0.05).

CONCLUSION

A discrepancy was found in reports of the most common causative food between caregiver-reported and physician-diagnosed cases of FPIES.

Overviewing allergy epidemiology in Japan - Findings from birth cohorts (JECS and T-Child study)

The escalating global allergy epidemic has emerged as a pressing and persistent challenge, exerting a profound impact on human health systems across centuries. This burgeoning predicament can be attributed to contemporary lifestyles, environmental influences, and genetic predispositions. The manifestation of allergy-related factors exhibits dynamic fluctuations contingent on temporal shifts, geographical distinctions, cultural variances, and diverse demographic strata. In this review, we present recent epidemiological insights derived from two distinct birth cohorts: the Japan Environment and Children's Study (JECS), encompassing the entirety of Japan, and the Tokyo Children's Health, Illness, and Development Study (T-Child Study) within Tokyo. Through this comprehensive review, we offer a comprehensive overview of the latest epidemiological discoveries stemming from these pivotal Japanese birth cohorts, thereby affording a unique opportunity to deliberate on imperative strategies for the optimal management of the allergy epidemic.

Maternal antibiotic exposure and childhood allergies: The Japan Environment and Children's Study

Background

The association of maternal antibiotic exposure during pregnancy with childhood allergic diseases remains unclear.

Objective

We aimed to evaluate the association of maternal exposure to antibiotic use during pregnancy with childhood allergic diseases up to the age of 3 years by using data from a large Japanese birth cohort.

Methods

We analyzed data on 78,678 pregnant women and their offspring aged 0 to 3 years. Prenatal antibiotic exposure was defined as the use of any antimicrobial agent during pregnancy. Information was collected from maternal interviews and medical record transcripts. The outcome variables in this study included preschool asthma, wheezing, food allergy, atopic dermatitis, eczema, allergic rhinoconjunctivitis, and any allergic disease. We used logistic regression analysis to evaluate the association of antibiotic exposure during pregnancy with childhood allergic diseases.

Results

Among the participating mothers, 28.5% used antibiotics during pregnancy. Antibiotic exposure during pregnancy was associated with preschool asthma (adjusted odds ratio [aOR] = 1.12 [95% CI = 1.06-1.19]), wheezing (aOR = 1.11 [95% CI = 1.07-1.15]), allergic rhinoconjunctivitis (aOR = 1.10 [95% CI = 1.03-1.17]) and any allergic disease (aOR = 1.09 [95% CI = 1.05-1.14]) in offspring up to age 3 years. In contrast, maternal antibiotic use was not associated with food allergies, atopic dermatitis, or eczema. Additionally, the significant associations were not influenced by the timing of antibiotic exposure, sex of the infants, or maternal history of allergies.

Conclusion

Maternal antibiotic exposure during pregnancy is associated with an increased risk of childhood respiratory allergies.

The disease burden of pediatric patients with atopic dermatitis in Japan

BACKGROUND

Atopic dermatitis (AD) is a chronic skin condition that is associated with significant patient burden and decreased health-related quality of life (HRQoL). We report results of the real-world Epidemiology of Children with Atopic Dermatitis Reporting on their Experience study in Japanese pediatric patients, focusing on the impact of AD severity on disease burden.

METHODS

Children and adolescents aged 6 months to 17 years (or their caregivers/parents) completed an online survey between September 26, 2018, and March 5, 2019. Patients with diagnosed AD (i.e., met International Study of Asthma and Allergies in Childhood criteria and had a self-reported AD diagnosis) were evaluated for disease severity using the Patient-Oriented Eczema Measure (POEM). Impact of AD severity on AD symptoms (itching, pain, and sleep disturbance), disease flares, atopic comorbidities, healthcare resource utilization, school days missed, and HRQoL were assessed.

RESULTS

Of 5702 Japanese pediatric patients, 547 had diagnosed AD and were included in this analysis. Based on POEM scores, AD severity was clear/mild in 346 patients (63.3%), moderate in 177 (32.5%), and severe in 24 (4.4%). Across all age groups (i.e., less than 6, 6-11, and 12-17 years), increased AD severity was associated with increased AD symptom severity, number of flares, atopic comorbidities, healthcare resource utilization, and school absences, as well as worsened HRQoL.

CONCLUSIONS

This population-based study of Japanese children and adolescents showed that greater AD severity had a high impact on disease burden.

Prenatal exposure to selenium, mercury, and manganese during pregnancy and allergic diseases in early childhood: The Japan Environment and Children's study

BACKGROUND

Prenatal exposure to metallic elements may adversely affect early childhood health. However, more evidence is needed as population-based cohort studies are currently limited.

OBJECTIVES

We aimed to examine the associations between prenatal metallic (mercury, selenium, and manganese) exposure and the risk of allergic diseases in early childhood until three years of age.

METHODS

The data from 94,794 mother-infant pairs, who participated in the Japan Environment and Children's study, were used in this study. Prenatal metallic element exposure was measured in maternal blood collected during mid-pregnancy. The incidence of atopic dermatitis, food allergies, asthma, and allergic rhinitis during the first three years of life was prospectively investigated using self-reports of physician-diagnosed allergies. A multivariable modified Poisson regression model was used to estimate the cumulative incidence ratio and their 95% confidence intervals of allergic diseases associated with prenatal exposure to mercury, selenium, and manganese. We further evaluated the interaction between mercury and selenium exposures in this association.

RESULTS

We confirmed 26,238 cases of childhood allergic diseases: atopic dermatitis, food allergies, asthma, and allergic rhinitis in 9,715 (10.3%), 10,897 (11.5%), and 9,857 (10.4%), 4,630 (4.9%), respectively. No association was found between prenatal mercury or manganese exposure and the risk of allergic diseases. Prenatal selenium exposure was inversely associated with atopic dermatitis, food allergies, allergic rhinitis, and any allergic diseases, but not with asthma. These inverse associations were more pronounced for lower mercury exposures than for higher exposures.

CONCLUSIONS

Our findings suggest that prenatal exposure to selenium may be beneficial for reducing the risk of atopic dermatitis, food allergies, allergic rhinitis, and any allergic diseases in early childhood, especially with lower prenatal mercury exposure.

Saliva contact during infancy and allergy development in school-age children

Background

Parent-child saliva contact during infancy might stimulate the child's immune system for effective allergy prevention. However, few studies have investigated its relation to allergy development in school-age children.

Objective

We sought to investigate the relationship between parent-child saliva contact during infancy and allergy development at school age.

Methods

We performed a large multicenter cross-sectional study involving Japanese school children and their parents. The self-administered questionnaires including questions from the International Study of Asthma and Allergies in Childhood were distributed to 3570 elementary and junior high school children in 2 local cities. Data were analyzed for the relationship between saliva contact during infancy (age <12 months) and the risk of allergy development, specifically eczema, allergic rhinitis, and asthma. For detailed Methods, please see the Methods section in this article's Online Repository at www.jacionline.org.

Results

The valid response rate was 94.7%. The mean and median age of children was 10.8 ± 2.7 and 11 (interquartile range, 9-13) years, respectively. Saliva contact via sharing eating utensils during infancy was significantly associated with a lower risk of eczema (odds ratio, 0.53; 95% CI, 0.34-0.83) at school age. Saliva contact via parental sucking of pacifiers was significantly associated with a lower risk of eczema (odds ratio, 0.24; 95% CI, 0.10-0.60) and allergic rhinitis (odds ratio, 0.33; 95% CI, 0.15-0.73), and had a borderline association with the risk of asthma in school-age children.

Conclusions

Saliva contact during infancy may reduce the risk of developing eczema and allergic rhinitis in school-age children.

The role of basophil activation test and component-resolved diagnostics in the workup of egg allergy in children at low risk for severe allergic reactions: A real-life study

BACKGROUND

The gold standard for diagnosing egg allergy in children is the oral food challenge (OFC). However, OFCs are time-consuming and risky procedures. Our study aimed to evaluate the utility of the basophil activation test (BAT) and component-resolved diagnostic in the diagnostic workup of children with egg allergy.

METHODS

Overall, 86 children aged 6 months to 17 years, suspected of egg allergy, underwent OFC with boiled egg according to international standardized protocols. BAT and specific immunoglobulin E (sIgE) testing to component egg proteins (Gal d 1-4) were also performed.

RESULTS

Of the 22 children who reacted to boiled egg, only one experienced anaphylaxis during the challenge. BAT was performed in samples obtained by 75 of the 86 patients of our cohort. Egg white and yolk protein extracts induced CD63 upregulation in the egg-allergic (EA) children compared with sensitized children that tolerated boiled egg (we registered an overall mean of CD63 expression in the EA population of 44.4% [SD 34.1] for egg white and 34.7% [SD 31.3] for egg yolk vs. 12.5% [SD 19.1] and 10.0% [SD 16.0] in sensitized children). BAT could discriminate between true egg allergy and egg sensitization in our population. As a second-line diagnostic step, the positivity of BAT for egg white or Gal d 1-sIgE resulted in a 40.9% OFC reduction, especially for those with a positive outcome.

CONCLUSION

The BAT may be implemented in the diagnostic workup of egg allergy in children and, in a stepwise approach, separately or combined with Gal d 1-sIgE, may predict the allergic status and reduce the number of positive OFCs in children with egg allergy at low risk for severe reactions.

Enhanced early skin treatment for atopic dermatitis in infants reduces food allergy

BACKGROUND

Early-onset atopic dermatitis is a strong risk factor for food allergy, suggesting that early effective treatment may prevent transcutaneous sensitization.

OBJECTIVES

This study tested whether enhanced treatment of atopic dermatitis to clinically affected and unaffected skin is more effective in preventing hen's egg allergy than reactive treatment to clinically affected skin only.

METHODS

This was a multicenter, parallel-group, open-label, assessor-blind, randomized controlled trial (PACI [Prevention of Allergy via Cutaneous Intervention] study). This study enrolled infants 7-13 weeks old with atopic dermatitis and randomly assigned infants in a 1:1 ratio to enhanced early skin treatment or conventional reactive treatment using topical corticosteroids (TCSs). The primary outcome was the proportion of immediate hen's egg allergy confirmed by oral food challenge at 28 weeks of age.

RESULTS

This study enrolled 650 infants and analyzed 640 infants (enhanced [n = 318] or conventional [n = 322] treatment). Enhanced treatment significantly reduced hen's egg allergy compared with the conventional treatment (31.4% vs 41.9%, P = .0028; risk difference: -10.5%, upper bound of a 1-sided CI: -3.0%), while it lowered body weight (mean difference: -422 g, 95% CI: -553 to -292 g) and height (mean difference: -0.8 cm, 95% CI: -1.22 to -0.33 cm) at 28 weeks of age.

CONCLUSIONS

This study highlighted the potential of well-controlled atopic dermatitis management as a component of a hen's egg allergy prevention strategy. The enhanced treatment protocol of this trial should be modified before it can be considered as an approach to prevent hen's egg allergy in daily practice to avoid the adverse effects of TCSs. After remission induction by TCSs, maintenance therapy with lower potency TCSs or other topical therapies might be considered as alternative proactive treatments to overcome the safety concerns of TCSs.

Low-Dose Oral Challenge Test in Pediatric Patients With Peanut Allergy: Tolerance Assessment of a Trace 5 mg Peanut Test After Symptom Induction With a 500 mg Test

Introduction Peanut allergy (PA) represents a significant public health concern, particularly prevalent in Western countries. Children at high risk for PA may undergo a low-dose oral food challenge (OFC). However, if the result is positive, complete elimination of peanuts from the diet is recommended, and further trace OFC is typically not performed.  Material and methods This cross-sectional study retrospectively examined the rate of positive peanut OFC with a total peanut load of 5 mg in children who tested positive with a total peanut load of 500 mg. Patient information was gathered from medical records. The primary endpoint was the rate at which children who tested positive in the OFC with 500 mg of peanut butter also tested positive with 5 mg of peanut butter equivalent.  Results Among 32 children who underwent an OFC with a total peanut load of 500 mg, two were excluded for not meeting the criteria. Among the remaining 30 children, 14 (46.7%) had a positive 500 mg peanut OFC test, and three (10%) experienced an anaphylactic reaction. Those who tested positive for the OFC had higher peanut-specific and Ara h2-specific immunoglobulin E (IgE) antibodies. An OFC with 5 mg of peanuts performed on 10 of the 14 patients who tested positive for 500 mg of peanuts showed no positive results. Conclusion The results of this study suggest that children with severe PA who exhibit positive symptoms to a total peanut load of 500 mg can tolerate a 5 mg dose of peanuts and should be considered for an OFC.

Development of an action plan for acute food protein-induced enterocolitis syndrome in Japan

Reports of food protein-induced enterocolitis syndrome (FPIES) in Japan have been increasing. However, the disease itself and the treatment options are poorly understood by both patients and medical professionals. The objective of this study is to develop an action plan for acute FPIES in Japan. We prepared a single-sheet action plan that describes the management of acute FPIES episodes for caregivers on one side and medical professionals on the reverse side. To evaluate the content of the action plan, we distributed a questionnaire to caregivers of patients with FPIES and to physicians who would encounter patients with FPIES. Changes to the FPIES action plan were made based on the feedback from the participants. The Delphi method was utilized to finalize the action plan. The participants of the initial survey found the action plan to be useful but the process for determining severity to be impractical. After discussion, the authors made appropriate improvements. By the Delphi method, consensus was reached on the revised FPIES action plan. In conclusion, this Japanese FPIES action plan was created by physicians from multiple subspecialties and caregivers of patients with FPIES. The action plan may improve the management of acute FPIES reactions in the Japanese community.

Maternal heated tobacco product use during pregnancy and allergy in offspring

BACKGROUND

Little is known about the association between maternal use of heated tobacco products (HTPs) during pregnancy and the onset of allergy among offspring. This study aimed to determine whether maternal HTP smoking is associated with allergy in their offspring and to evaluate the potential dose-response association.

METHODS

In this web-based, cross-sectional survey conducted in July and August 2021 in Japan, we investigated 5688 pairs of postpartum women and infants (<3 years). Clinical diagnoses of infant asthma, rhinitis, conjunctivitis, or atopic dermatitis were reported. Using multilevel Poisson regression, we estimated the prevalence ratios (PRs) and 95% confidence intervals (CIs) of allergy in infants with HTP smoking categories cross-classified by pregnancy periods, and adjusted for potential covariates including maternal cigarette smoking and partner's smoking status. Non-smokers served as the reference group.

RESULTS

In total, 2.4% women smoked HTPs during pregnancy. Allergy occurred in 7.8% of the infants. The prevalence of allergy increased among the offspring of current HTP smokers during pregnancy at 15.2% (PR = 1.98, 95% CI 1.28-3.05); this association was the most pronounced during the first trimester but attenuated before pregnancy and postpartum. Dose-response associations were observed, for example a one-unit increase in daily maternal HTP use during pregnancy was associated with a 5% increase in allergy onset. Sub-group analyses excluding cigarette smokers during pregnancy and sensitivity analyses using the International Study of Asthma and Allergies in Childhood questionnaire showed a similar pattern.

CONCLUSIONS

Maternal HTP smoking during pregnancy is associated with allergy in the offspring.

A Meta-Analysis of the Prevalence of Wheat Allergy Worldwide

Wheat allergy is a primary disease of food allergy, and its global prevalence is unclear. This study aimed to characterize the latest worldwide prevalence of wheat allergy based on five different diagnostic methods. Study searches were conducted in Web of Science, PubMed, Ovid LWW, and Cochrane database, with a time limit of 1 January 2007 to 1 September 2022. The review and screening of the articles was undertaken by two independent reviewers. The statistical analysis was conducted by R. A total of 56 articles were finally included. The prevalence of wheat allergy was 0.63% (95% CI: 0.43-0.87%) for self-reported, 0.70% (95% CI: 0.18-1.22%) for self-reported physician-diagnosed, 0.22% (95%CI: 0.07-0.65%) for skin prick test positive, 0.97% (95% CI: 0.43-2.20%) for specific immunoglobulin E positive, and 0.04% (95% CI: 0-0.16%) for food challenge. However, food challenge can be largely subjective, and the results were only based two countries, so the prevalence of wheat allergy confirmed by food challenge may be not entirely trustworthy. In conclusion, investigating the prevalence of wheat allergy in the real world as accurately as possible will contribute to the prevention, management, and risk assessment of wheat allergy.

Combination of heat-killed Lactiplantibacillus plantarum YIT 0132 (LP0132) and oral immunotherapy in cow's milk allergy: a randomised controlled trial

Safer and more effective cow milk (CM)-oral immunotherapy that does not induce allergic reactions has not yet been standardised. We sought to explore the efficacy and feasibility of a combination of heat-killed Lactiplantibacillus plantarum YIT 0132 (LP0132) and oral immunotherapy for treating IgE-mediated cow milk allergy (CMA). We conducted a 24-week, double-blind, randomised (1:1), two-arm, parallel-group, placebo-controlled, phase 2 trial of LP0132 intervention for treating IgE-mediated CMA in children aged 1-18 years (n=60) from January 29, 2018 to July 12, 2019 in Tokyo, Japan. Participants were randomly assigned to the LP0132 group receiving citrus juice fermented with LP0132 or to the control group receiving citrus juice without. Both groups received low-dose slow oral immunotherapy with CM. The primary outcome was improved tolerance to CM, proven by the CM challenge test at 24 weeks. Secondary outcomes were changes in serum biomarkers of serum-specific β-lactoglobulin-IgE (sIgE) and β-lactoglobulin-IgG4 (sIgG4). Exploratory outcomes included changes in serum cytokine levels and gut microbiota composition. A total of 61 participants were included. Finally, 31 children were assigned to the LP0132 group and 30 to the control group, respectively. After the intervention, 41.4 and 37.9% of the participants in the LP0132 and control groups, respectively, showed improved tolerance to CM. In serum biomarkers after the intervention, the sIgG4 level was significantly higher, and interleukin (IL)-5 and IL-9 were significantly lower, in the LP0132 group than in the control group. In the gut microbiome, the α-diversity and Lachnospiraceae increased significantly in the LP0132 group, and Lachnospiraceae after the intervention was significantly higher in the LP0132 group than in the control group. In conclusion, low-dose oral immunotherapy with modulating gut microbiota might be a safer and more effective approach for treating cow's milk allergy.

mRNAs in skin surface lipids unveiled atopic dermatitis at 1 month

BACKGROUND

The molecular pathogenesis of atopic dermatitis (AD), presenting skin barrier dysfunction and abnormal inflammations around 1-2 months, is unreported.

OBJECTIVE

We aimed to examine the molecular pathogenesis of very early-onset AD by skin surface lipid-RNA (SSL-RNA) using a non-invasive technology in infants aged 1 and 2 months from a prospective cohort.

METHODS

We collected sebum by oil-blotting film of infants aged 1 and 2 months and analysed RNAs in their sebum. We diagnosed AD according to the United Kingdom Working Party's criteria.

RESULTS

Infants with AD aged 1 month showed lower expression of genes related to various lipid metabolism and synthesis, antimicrobial peptides, tight junctions, desmosomes and keratinization. They also had higher expression of several genes involved in Th2-, Th17- and Th22-type immune responses and lower expression of negative regulators of inflammation. In addition, gene expressions related to innate immunity were higher in AD infants. Infants aged 1 month with neonatal acne and diagnosed with AD aged 2 months already had gene expression patterns similar to AD aged 1 month in terms of redox, lipid synthesis, metabolism and barrier-related gene expression.

CONCLUSION

We identified molecular changes in barrier function and inflammatory markers that characterize the pathophysiology of AD in infants aged 1 month. We also revealed that neonatal acne at 1 month could predict the subsequent development of AD by sebum transcriptome data.

Relationship between Food Allergy and Endotoxin Concentration and the Toleration Status at 2 Years: The Japan Environment and Children's Study

Changes in household endotoxin concentration may affect the prognosis of food allergy (FA), but data on the association between household endotoxin concentration and an already-developed FA are scarce. Thus, we investigated the association between environmental endotoxin exposure and tolerance to hen's egg (HE) and cow's milk (CM) using data from children participating in the Japan Environment and Children's Study who had HE allergies (n = 204) and CM allergy (n = 72) in their first year of life. We grouped the endotoxin results into quartiles 1-4 (Q1-Q4). In children with HE allergy and with CM allergy, there was no significant difference in the prevalence of tolerance to HE and CM at 2 years old when comparing endotoxin levels of the children in Q1 with those in Q2, Q3, and Q4, respectively. However, subgroup analyses by the presence of eczema and causal foods revealed that children in Q1 had a lower prevalence of tolerance to foods in some subgroup analyses and lower causal allergen-specific immunoglobulin G4 levels. Although an individually based approach against endotoxin according to background characteristics, such as eczema and causal foods, is necessary, preventing excessive endotoxin removal might contribute to FA resolution in some children.

Season of birth and atopic dermatitis in early infancy: results from the Japan Environment and Children's Study

BACKGROUND

Atopic dermatitis (AD) is reported to be more prevalent in children who were born in autumn than in spring. Here, we investigated how early the association between season of birth and eczema or AD can be observed in the postnatal period. We also examined whether specific prevalence outcomes for infant eczema and AD differed according to sex and maternal history of allergic disease in a large Japanese cohort.

METHODS

Using data of 81,615 infants from the Japan Environment and Children's Study, we examined the associations of birth month or season with four different outcomes-eczema at 1 month, 6 months, and 1 year of age and physician-diagnosed AD up to 1 year of age-using multiple logistic regression analysis. We also analyzed the effect of maternal history of allergic disease on these outcomes stratified by infant sex.

RESULTS

The risk of eczema at 1 month was highest in infants born in July. In contrast, infants born in autumn had higher risks of eczema at 6 months (adjusted odds ratio [aOR], 2.19; 95% confidence interval [CI], 2.10-2.30) and at 1 year (aOR, 1.08; 95% CI, 1.02-1.14) and of physician-diagnosed AD up to 1 year of age (aOR, 1.33; 95% CI, 1.20-1.47) compared with infants born in spring. Eczema and AD were more prevalent in infants with a maternal history of allergic disease, particularly boys.

CONCLUSIONS

Our findings suggest that the prevalence of AD is associated with the season of observation. Eczema is prevalent in infants born in autumn, and this phenomenon was observed in infants as young as 6 months old. The risk associated with being born in autumn was particularly clear in boys with a maternal history of allergic disease.

TRIAL REGISTRATION

UMIN000030786.

Allergic reactions to propofol in adult patients with egg or soybean allergy: a retrospective cohort study from a large database of a single institute

BACKGROUND

In recent years, many reports have indicated that propofol is safe to administer to patients with egg/soybean allergy in Western countries. Egg allergy is more frequent in Asia, but there are limited reports regarding allergic reactions to propofol use among adults. This study aimed to determine whether propofol causes allergic reactions in patients with egg/soybean allergy.

METHODS

Adult patients who underwent surgery involving anesthesiologists from 2018 to 2021 were included. In all patients, we reviewed food allergy information in their electronic medical record and extracted anesthetics. Patients with egg/soybean allergy were subdivided into two groups on the basis of intraoperative use of propofol. We evaluated each group for allergic reactions within 24 h after the induction of anesthesia. The primary outcome was a relative risk of allergic reactions after propofol use for patients with egg/soybean allergy.

RESULTS

In total, 22,111 patients with 28,710 anesthesia records were identified. Among patients with egg/soybean allergy, 173 (0.8%) patients and 237 (0.8%) anesthesia records were included in the study. Among the records of egg-/soybean-allergic patients, 151 were administered propofol, and 86 were not. The relative risk of allergic reactions after propofol use for patients with egg/soybean allergy was 1.14 (95% confidence interval, 0.10-12.4; p = 0.74).

CONCLUSION

The use of propofol in patients with egg/soybean allergy does not significantly increase the relative risk of allergic reactions. Therefore, anesthesiologists can appropriately determine the indication for propofol, even in patients with egg/soybean allergy.

TRIAL REGISTRATION

UMIN-CTN, UMIN000049321 registered 26 October 2022 - retrospectively registered, https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000056167.

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.

Endotoxin concentration and persistent eczema in early childhood

Although endotoxin concentration in the environment is negatively associated with atopic dermatitis (AD) onset in early childhood, the association between endotoxin concentration in the environment and eczema resolution in children with preexisting eczema is unclear. The aim of this study was to evaluate the association between endotoxin concentration in house dust and eczema persistence in young children. The authors used data from children participating in JECS (Japan Environment and Children's Study). In children who had AD or AD-like lesions at the age of 1 year, the authors investigated the association between the prevalence of eczema at the age of 3 years and endotoxin concentration (categorized by quartiles) in the dust on children's mattresses at the ages of 1.5 and 3 years. This study included 605 children. Eczema was significantly less prevalent among children whose mattresses were in the second and third quartiles of endotoxin concentration when they were 18 months old than among children whose mattresses were in the first quartile (adjusted odds ratio, 0.57 [95% confidence interval, 0.35-0.93] and adjusted odds ratio, 0.49 [95% confidence interval, 0.29-0.83], respectively). Moreover, of the children with eczema at age 3 years, those whose mattresses had endotoxin concentrations in the first quartile had significantly worse sleep disturbance caused by itchy rash (>1 time per week) than did those whose mattresses were in the third and fourth quartiles (20.0% vs 3.3% and 3.7%, both p values < 0.01). The findings indicate that low endotoxin exposure is associated with a higher prevalence of persistent eczema during early childhood.

Sex differences in the association between smoking exposure and prevalence of wheeze and asthma in 3-year-old children

OBJECTIVE

We examined independent and joint associations between prenatal and postnatal smoking exposure and the prevalence of wheeze and asthma among 3-year-old Japanese children. Sex differences were also investigated.

METHODS

Smoking exposure, allergic symptoms, and potential confounding factor data were collected using a self-administered questionnaire. Wheeze was defined on the basis of the International Study of Asthma and Allergies in Childhood criteria. Physician-diagnosed asthma was considered to be present if a physician had diagnosed the child with asthma any time before the survey was administered.

RESULTS

There were 6402 pediatric participants in this study. Maternal smoking throughout pregnancy and household smoking exposure during the first year of life were associated with an increased prevalence of wheeze among girls but not boys (adjusted odds ratio (OR) [95% CI] = 2.00 [1.13-3.42] and 1.34 [1.07-1.68], respectively). Girls exposed to both prenatal maternal smoking and postnatal household smoking exposure had a significantly higher prevalence of wheeze and physician-diagnosed asthma compared with girls without these exposures (adjusted OR [95% CI] = 2.06 [1.39-3.01] and 1.86 [1.01-3.26], respectively). No association was observed between perinatal smoking exposure and the prevalence of wheeze or asthma among boys. Significant interactions between sex and smoking exposure affecting wheeze and asthma were also found (p for interaction = 0.0003 and 0.01, respectively).

CONCLUSION

We found a positive association between perinatal smoking exposure and the prevalence of wheeze and asthma only among girls. Effects of perinatal smoking exposure on wheeze and asthma might be sex specific. Further research is required.

How a Family History of Allergic Diseases Influences Food Allergy in Children: The Japan Environment and Children's Study

The influence of family allergic history on food allergy in offspring in Japan is unknown. We analyzed data from a nationwide birth cohort study using logistic regression models to examine the associations of maternal, paternal, and both parental histories of allergic diseases (food allergy, atopic dermatitis, asthma, and rhinitis) with their child’s food allergy at 1.5 and 3 years of age. This analysis included 69,379 singleton full-term mothers and 37,179 fathers and their children. All parental histories of allergic diseases showed significant positive associations with their child’s food allergy. When both parents had a history of allergic diseases, the adjusted odds ratio (aOR) tended to be higher than when either parent had allergic diseases (p for trend < 0.0001). The highest aOR was detected when both parents had food allergy (2.60; 95% confidential interval, 1.58−4.27), and the aOR was 1.71 when either parent had food allergy (95% confidential interval, 1.54−1.91). The aORs were attenuated but still had significant positive associations after adjusting for the child’s atopic dermatitis, a risk factor for allergy development. In conclusion, all parental allergic diseases were significantly positively associated with their child’s food allergy. The effect of family history showed a stepwise increase in risk from either parent to both parents, and the highest risk of allergic disease was a parental history of food allergy.

Remission of Acute Food Protein-Induced Enterocolitis Syndrome Confirmed by Oral Food Challenges in Japan

The oral food challenge test (OFC) is the gold standard for evaluating the remission of food protein-induced enterocolitis syndrome (FPIES). Few acute FPIES remissions confirmed by OFC were reported. This study aimed to examine the OFC for Japanese children with acute FPIES to evaluate its remission. A retrospective cohort study was performed on children with acute FPIES with remission evaluation by OFC based on one food challenge dose (1/50, 1/10, 1/2, and full dose per day). Acute FPIES remission was observed in 65.2% of patients (15/23 patients). Vomiting episodes occurred with 1/50 full doses on the first day among 75% of positive patients. The median duration between the onset and OFC was 14 months (IQR, 8-24 months). Soy was the most common causative food, followed by egg yolk, milk, and wheat. All patients could receive OFC safely without intensive care unit care, based on the FPIES OFC protocol. The remission rate of acute FPIES was high. However, vomiting episodes commonly occurred with 1/50 full doses on the first day. This study suggested that our OFC protocol for acute FPIES was safe and feasible, but it might be safer for some patients to start at a minimal loading dose.

Maternal dietary folate intake with folic acid supplements and wheeze and eczema in children aged 2 years in the Japan Environment and Children’s Study

Maternal intake of folic acid supplements is reportedly associated with the risk of early-onset allergies in offspring. However, only a few studies have considered the intake of both folic acid supplements and dietary folate. Here, the relationship between maternal intake of folic acid supplements and allergic symptoms such as wheeze and eczema in offspring was analyzed while considering dietary folate intake. We examined 84,361 mothers and 85,114 children in the Japan Environment and Children’s Study. The participants were divided into three groups depending on maternal folic acid supplementation (“no use,” “occasional use,” and “daily use”). Each group was then subdivided into three groups based on total folic acid and dietary folate intake. Outcomes were determined considering the wheeze and eczema status of each child at the age of 2 years. The status was based on the International Study of Asthma and Allergies in Childhood. It was found that 22.1% of the mothers took folic acid supplements daily. In contrast, 56.3% of the mothers did not take these supplements. Maternal intake of folic acid supplements was not associated with wheeze and eczema in the offspring. In contrast, only dietary folate intake was positively associated with wheeze at the age of 2 (adjusted odds ratio, 1.103; 95% confidence interval, 1.003–1.212). However, there is no scientific evidence of a biological mechanism that clarifies this result. Potential confounders such as other nutrition, outdoor/indoor air pollution, and genetic factors may have affected the results. Therefore, further studies on the association between maternal intake of folic acid and allergic symptoms at the age of 3 or above are needed to confirm the results of this study.

Trial registration

UMIN Clinical Trials Registry (number: UMIN000030786)

English Version of Clinical Practice Guidelines for the Management of Atopic Dermatitis 2021

This is the English version of the Clinical Practice Guidelines for the Management of Atopic Dermatitis 2021. Atopic dermatitis (AD) is a disease characterized by relapsing eczema with pruritus as a primary lesion. In Japan, from the perspective of evidence-based medicine, the current strategies for the treatment of AD consist of three primary measures: (i) use of topical corticosteroids, tacrolimus ointment, and delgocitinib ointment as the main treatment of the inflammation; (ii) topical application of emollients to treat the cutaneous barrier dysfunction; and (iii) avoidance of apparent exacerbating factors, psychological counseling, and advice about daily life. In the present revised guidelines, descriptions of three new drugs, namely, dupilumab, delgocitinib, and baricitinib, have been added. The guidelines present recommendations to review clinical research articles, evaluate the balance between the advantages and disadvantages of medical activities, and optimize medical activity-related patient outcomes with respect to several important points requiring decision-making in clinical practice.

The association between early formula and reduced risk of cow’s milk allergy during the first three year of life: a Japanese cohort study

Background

Our recent observational study showed that regular consumption of cow’s milk (CM) formula during early infancy (3–6 months old) was associated with a reduced risk of CM allergy (CMA) at 12 months old. However, the long-term association is unclear. The present study was aimed to examine how long this inverse association persists after 12 months old.

Methods

This study used the dataset of an ongoing nationwide prospective cohort, the Japan Environment and Children’s Study, in which participants were registered between January 2011 and March 2014. We analyzed 65,568 children followed-up until 36 months old. The exposure factors were the consumption statuses of formula milk from 0–3, 3–6, and 6–12 months old. The primary outcome was the prevalence of CMA at 6, 12, 18, 24 and 36 months old. CMA was defined as an allergic reaction and sensitization to CM protein in an individual with no or limited intake of this protein at the evaluation time, combined with physician-diagnosed food allergy. Multivariable regression models were used to estimate the association between the periods of formula consumption and the prevalence of CMA.

Results

The prevalence of CMA increased with a peak of 1.51% at 18 months old and then declined to 0.79% at 36 months old. Formula milk from 3–6 months old was associated with a reduced risk of CMA throughout the first 3 years of life, although the extent of the reduction was mitigated with age (adjusted relative risk: [95% confidence interval]: 0.19 [0.10–0.34] at 12 months old, 0.23 [0.16–0.33] at 18 months old, 0.41 [0.26–0.64] at 24 months old, and 0.47 [0.26–0.80] at 36 months old). The association between early formula and CMA were observed in both children with and without eczema, but more prominent and long-lasting in the former than the latter.

Conclusions

Regular exposure to CM protein during infancy was associated with a reduced prevalence of CMA during early childhood. At present, however, this observational study does not necessarily encourage formula feeding, and randomized controlled trials are warranted to confirm the findings and their significance.

Prevalence of IgE-mediated cow milk, egg, and peanut allergy in young Singapore children

Background

The rising prevalence of food allergy reported in the United States, UK, and Australia may be attributable to the rise in peanut allergy prevalence. The food allergy prevalence in other parts of the world such as Asia is, however, less well documented.

Objective

This study aimed to evaluate the prevalence of cow's milk, egg, and peanut allergies in a general population of Singaporean children below 30 months of age.

Methods

A total of 4,115 children from the general population who attended well-baby visits between 2011 and 2015 completed standardized questionnaires to elicit a convincing history of food allergy to estimate the population prevalence of food allergies.

Results

The prevalence of a convincing history of cow's milk allergy was 0.51% (95% confidence interval [CI], 0.3-0.7), hen's egg allergy 1.43% (95% CI, 1.1-1.8), and peanut allergy 0.27% (95% CI, 0.12-0.42). Of the 15 of 59 children with a convincing history of hen's egg allergy who consented, 12 (80%) had corroborative positive skin prick tests.

Conclusion

The prevalence of food allergy, in particular peanut allergy, in children below 2 years of age is lower in this South East Asian population than reported in Western cohorts. Further research should focus on deciphering differential risk factors for food allergy across different geographical locations.

Prevalence of infantile wheezing and eczema in a metropolitan city in Japan: A complete census survey

Infantile wheezing and eczema are associated with the subsequent onset of asthma and other atopic diseases. However, there are no large population-based surveys on infantile allergic symptoms in Japan. The objective of the study was to determine the prevalence of wheezing and asthma in infants in Nagoya, Japan. This population-based cross-sectional study was performed in the metropolitan city of Nagoya, Japan. We surveyed parents to ascertain the prevalence of wheezing and eczema in infants who attended group health checkups at 3, 18, and 36 months of age. Their parents completed modified questionnaires from the International Study of Asthma and Allergies in Childhood. More than 90% of the approximately 40,000 children in each study group living in the target area were included in the survey. The prevalence of wheezing was 8%, 17%, and 13% at 3, 18, and 36 months, respectively, and was characterized by birth season. The prevalence of eczema was 24%, 30%, and 31%, at 3, 18, and 36 months, respectively. Participants born in autumn and winter had a higher incidence of eczema in each age group. Three-quarters of the children had a parental history of allergic conditions. Parental allergic diseases and male gender are risk factors for wheezing and eczema in children. This survey had a high response rate and covered almost the entire population of the target age groups in a large city. We believe that the results of this study, therefore, provide a much higher level of confidence regarding the prevalence of allergies in infants in Japan than that in previous studies with limited cohorts.

Maternal BMI and allergy in children until 3 years of age (JECS)

Background

Maternal prepregnancy body mass index (BMI) may influence allergic diseases in the children who are the product of those pregnancies.

Objective

The purpose of our study was to investigate the association between mothers' prepregnancy BMI and the risk of physician-diagnosed asthma, food allergy (FA), and atopic dermatitis (AD) in their children during the first 3 years of life.

Methods

Data on mothers' prepregnancy BMI and physician-diagnosed asthma, FA, and AD in their children until the age of 3 years were obtained from the Japan Environment and Children's Study, a nationwide birth cohort study that has recruited 103,099 pregnant women between 2011 and 2014. Logistic regression analysis was used to analyze the results.

Results

We analyzed 67,204 mother-child pairs with available information on physician-diagnosed allergic diseases. The risk of asthma was significantly higher in children born to overweight mothers (adjusted OR [aOR] =1.17 [95% CI = 1.07-1.28]) and obese mothers (aOR = 1.28 [95% CI = 1.08-1.50]), whereas the risk of FA, cow's milk allergy, and egg allergy decreased significantly in children born to overweight mothers (aOR = 0.84 [95% CI = 0.76-0.92]; aOR = 0.78 [95% CI = 0.64-0.93]; and aOR = 0.83 [95% CI = 0.74-0.94]) and obese mothers (aOR = 0.81 [95% CI = 0.67-0.97]; aOR = 0.58 [95% CI = 0.36-0.87]; and aOR = 0.73 [95% CI = 0.56-0.93]) compared with in children born to normal weight mothers, respectively. Associations between AD and maternal BMI were not detected.

Conclusion

Our study showed that an increase in mothers' prepregnancy BMI was associated with an increase in asthma prevalence and a decrease in FA prevalence in their children. Further studies are needed to reveal the mechanisms associated with maternal BMI and pediatric allergic diseases.

Prenatal occupational disinfectant exposure and childhood allergies: the Japan Environment and Children's study

BACKGROUND

Disinfectants are widely used in the medical field, particularly recently because of the coronavirus pandemic, which has led to an increase in their use by both medical professionals and the general population. The objective of this study was to examine whether occupational disinfectant use during pregnancy was associated with the development of allergic disease in offspring at 3 years.

METHODS

We used data from 78 915 mother/child pairs who participated in the Japan Environment and Children's Study, which is a prospective birth cohort recruited between January 2011 and March 2014. We examined the associations between maternal disinfectant use during pregnancy and allergic diseases (asthma, eczema and food allergies) in children after adjustment for covariates including maternal postnatal return to work when the child was 1 year old by multivariate logistic regression.

RESULTS

Compared with those who never used disinfectants, participants who used disinfectant every day had a significantly higher risk of asthma in their offspring (adjusted OR 1.18, 95% CI 1.05 to 1.33 for 1-6 times a week; adjusted OR 1.26, 95% CI 1.05 to 1.52 for every day). The associations between disinfectant exposure and eczema were similar to those of asthma (adjusted OR 1.16, 95% CI 1.02 to 1.31 for 1-6 times a week; adjusted OR 1.29, 95% CI 1.06 to 1.57 for every day). We found a significant exposure-dependent relationship (p for trend <0.01). There were no significant associations between disinfectant use and food allergies.

CONCLUSION

Disinfectant use by pregnant women may be a risk factor for asthma and eczema in offspring. As disinfectants are an effective tool in the prevention of infectious diseases, replication of this study and further research into the mechanisms are warranted.

Sample management: a primary critical starting point for successful omics studies

Biological samples collected from cohort studies are widely utilized in molecular genetic studies and are typically stored long term for future applications, such as omics analyses. The extent of sample availability is determined by proper sample handling, and it is of primary importance for successful omics studies. However, questions on whether samples in long-term storage are properly available for omics experiments has been raised, because the quality and availability of such samples remain unknown until their actual utilization. In that perspective, several guidelines for proper sample management have been suggested. In addition, several researchers assessed how improper management damages sample using mock sample and suggested a set of requirements for sample handling. In this review, we present several considerations for sample handling eligible for omics studies. Focusing on birth cohorts, we describe the types of samples collected from which omics data were generated. This review ultimately aims to provide proper guidelines for sample handling for successful human omics studies.