Maternal diet before and during pregnancy and risk of asthma and allergic rhinitis in children

The Early Appearance of Asthma and Its Relationship with Gut Microbiota: A Narrative Review

Asthma is, worldwide, the most frequent non-communicable disease affecting both children and adults, with high morbidity and relatively low mortality, compared to other chronic diseases. In recent decades, the prevalence of asthma has increased in the pediatric population, and, in general, the risk of developing asthma and asthma-like symptoms is higher in children during the first years of life. The "gut-lung axis" concept explains how the gut microbiota influences lung immune function, acting both directly, by stimulating the innate immune system, and indirectly, through the metabolites it generates. Thus, the process of intestinal microbial colonization of the newborn is crucial for his/her future health, and the alterations that might generate dysbiosis during the first 100 days of life are most influential in promoting hypersensitivity diseases. That is why this period is termed the "critical window". This paper reviews the published evidence on the numerous factors that can act by modifying the profile of the intestinal microbiota of the infant, thereby promoting or inhibiting the risk of asthma later in life. The following factors are specifically addressed in depth here: diet during pregnancy, maternal adherence to a Mediterranean diet, mode of delivery, exposure to antibiotics, and type of infant feeding during the first three months of life.

Association between a maternal vegetarian diet during pregnancy and the occurrence of atopic dermatitis in children

BACKGROUND

Atopic dermatitis (AD) is rising globally, with genetics and environmental factors both playing crucial roles. Dietary habits during pregnancy are linked to children's allergic disease risk. However, limited studies have explored the association between maternal vegetarian diets during pregnancy and child AD. Therefore, this study aimed to examine the relationship between maternal vegetarian diets during pregnancy and the occurrence of AD in children.

METHODS

In this study, the Taiwan Birth Cohort Study (TBCS) database was used, comprising a representative national birth cohort of infants born in Taiwan in 2005. Of 24,200 mother-child pairs in the database, 20,172 completed face-to-face interviews at 6 and 18 months. Employing a 1:10 matching strategy based on maternal age, education level, and child sex, 408 mothers who followed a vegetarian diet during pregnancy were matched with 4080 nonvegetarian mothers. This resulted in a final dataset of 4488 subjects. Logistic regression was used to explore the association between maternal vegetarian diets during pregnancy and the occurrence of AD in children.

RESULTS

Among the TBCS participants, there were 292 (1.8%) mothers who adhered to lacto-ovo vegetarianism and 116 (0.7%) mothers who adhered to veganism, totaling 408 (2.4%) vegetarians during pregnancy. Compared to children of nonvegetarian mothers, children of mothers who followed a vegetarian diet during pregnancy showed a lower risk of developing AD before 18 months of age (OR = 0.65, 95% CI = 0.45-0.93, p = 0.018).

CONCLUSION

This study suggests that a vegetarian diet during pregnancy may lower the risk of AD in children. It is essential to carry out long-term follow-up to fully understand the impact of a mother's diet on allergic conditions.

Maternal pre-pregnancy BMI and offspring hyperactivity-inattention trajectories from 3 to 8 years in the EDEN birth cohort study

Evidence suggests obesity during pregnancy is associated with offspring attention-deficit hyperactivity disorder. However, studies have been limited to evaluating the association at a single age with inadequate data on important maternal lifestyle confounders and unmeasured familial confounding. The objective of this study was to examine the association between maternal pre-pregnancy body mass index (BMI) and child hyperactivity-inattention symptoms (HIS) at 3, 5 and 8 years. Data came from the EDEN mother-child cohort. Maternal pre-pregnancy BMI status (kg/m2) was calculated using pre-pregnancy weight and height (self-reported by mothers or measured by midwives). HIS were assessed by parental-report on the Strengths and Difficulties Questionnaire at 3, 5 and 8 years of age and used to derive developmental trajectories of HIS (n = 1428). Multivariate models were adjusted for confounders including socioeconomic status, maternal lifestyle behaviours (exercise, diet, smoking, alcohol), childcare and a stimulating home environment. Paternal BMI was used as a negative control. Compared to a normal pre-pregnancy BMI, pre-pregnancy maternal obesity was positively associated with increased odds of a high HIS trajectory between 3 and 8 years old in both unadjusted and adjusted logistic regression (adjusted odds ratio [aOR] 1.87 [95% CI 1.12, 3.12]). Pre-pregnancy overweight was not significantly associated after adjustment for confounders (aOR 1.32 [0.87, 2.01]). Maternal pre-pregnancy obesity, but not overweight, was associated with increased likelihood of a high HIS trajectory in children from 3 to 8 years old. This association persisted despite controlling for many important maternal lifestyle factors and paternal BMI. Further research is warranted to identify possible mediators involved.

Prenatal Maternal Stress and Pediatric Asthma Across Development: Adolescent Female-Specific Vulnerability

Prenatal maternal stress (PNMS) is linked to physical sequelae in offspring, including childhood asthma. This study sought to examine the roles of objective and subjective PNMS in the development of asthma at offspring ages 5 and 15. The sample included 815 mother-child dyads from the Mater Misericordiae Mothers' Hospital-University of Queensland Study of Pregnancy. PNMS was measured via retrospective self-report during pregnancy and 3-5 days after birth. Postnatal maternal stress was measured at offspring age 5. Objective PNMS was associated with elevated asthma risk at age 5 (OR 1.21, 95% CI 1.00, 1.45, p = 0.05), albeit not above concurrent postnatal stress. Sex moderated the association between PNMS and asthma at age 15, controlling for postnatal stress. Sex stratified analyses revealed a positive association between objective PNMS and age 15 asthma in females, but not males. Results provide evidence that PNMS may impact asthma outcomes in adolescence.

Prenatal and early-life antibiotic exposure and the risk of atopic dermatitis in children: A nationwide population-based cohort study

BACKGROUND

Atopic dermatitis (AD) contributes to substantial social and financial costs in public health care systems. Antibiotic exposure during pregnancy has been proposed as a risk factor, but findings remain inconsistent. The aim of this study was to investigate the association between prenatal antibiotic use and childhood AD.

METHODS

We performed a population-based cohort study using data collected from the Taiwan Maternal and Child Health Database from 2009 to 2016. Associations were determined using Cox proportional hazards model and were adjusted for several potential covariates, including maternal atopic disorders and gestational infections. Children with and without maternal predispositions of atopic diseases and postnatal antibiotic/acetaminophen exposures within 1 year were stratified to identify the subgroups at risk.

RESULTS

A total of 1,288,343 mother-child pairs were identified and 39.5% received antibiotics prenatally. Maternal antibiotic use during pregnancy was slightly positively associated with childhood AD (aHR 1.04, 95% CI 1.03-1.05), especially in the first and second trimesters. An apparent dose-response pattern was observed with an 8% increased risk when the exposure was ≥5 courses prenatally (aHR 1.08, 95% CI 1.06-1.11). Subgroup analysis showed the positive association remained significant regardless of postnatal infant antibiotic use, but the risk attenuated to null in infants who were not exposed to acetaminophen (aHR 1.01, 95% CI 0.96-1.05). The associations were higher in children whose mothers were without AD compared to those whose mothers were with AD. In addition, postnatal antibiotic or acetaminophen exposure of infants was associated with an increased risk of developing AD after 1 year of age.

CONCLUSION

Maternal antibiotic use during pregnancy was associated with an increased risk of childhood AD in a dose-related manner. Further research may be warranted to investigate this variable using a prospectively designed study, and also to examine whether or not this association is specifically related to pregnancy.

Early exposure to infections increases the risk of allergic rhinitis-a systematic review and meta-analysis

OBJECTIVE

The purpose of this study was to provide evidence for early life care by meta-analyzing the relationship between infection during pregnancy and up to 2 years of age and the risk of subsequent allergic rhinitis (AR).

METHODS

Published studies up to April 2022 were systematically searched in PubMed, Embase, Web of Science, Cochrane Library, SinoMed, CNKI, Wanfang Database, and VIP. Literature screening, including quality assessment, was performed, and the effect values (OR, HR, RR) and 95% confidence intervals (95% CI) of infection during pregnancy and up to 2 years of age and allergic rhinitis were extracted from each qualified study.

RESULTS

In total, 5 studies with a sample size of 82,256 reported the relationship between infection during pregnancy and offspring AR. Meta-analysis showed that maternal infection during pregnancy was associated with an increased risk of childhood AR in offspring (OR = 1.34, 95% CI: 1.08-1.67). Altogether, 13 studies with a sample size of 78,426 reported evidence of an association between infection within 2 years of age and subsequent AR in children. A pooled meta-analysis of all studies showed that early infection within 2 years of age was closely associated with childhood AR (OR = 1.25, 95% CI: 1.12-1.40), especially upper respiratory tract infection (OR = 1.32, 95% CI: 1.06-1.65) and gastrointestinal infections (OR = 1.37, 95% CI: 1.01-1.86), but ear infection showed similar results in the cohort study (OR = 1.13, 95% CI: 1.04-1.22).

CONCLUSION

Current evidence suggests that infection during pregnancy, early upper respiratory infection, gastrointestinal infections and ear infection within 2 years of age would increase the risk of AR in children. Therefore, the prevention of infection during pregnancy and in infancy and young children needs to be emphasized.

Lack of iron, zinc, and vitamins as a contributor to the etiology of atopic diseases

Micronutritional deficiencies are common in atopic children suffering from atopic dermatitis, food allergy, rhinitis, and asthma. A lack of iron, in particular, may impact immune activation with prolonged deficiencies of iron, zinc, vitamin A, and vitamin D associated with a Th2 signature, maturation of macrophages and dendritic cells (DCs), and the generation of IgE antibodies. In contrast, the sufficiency of these micronutrients establishes immune resilience, promotion of regulatory cells, and tolerance induction. As micronutritional deficiencies mimic an infection, the body's innate response is to limit access to these nutrients and also impede their dietary uptake. Here, we summarize our current understanding of the physiological function of iron, zinc, and vitamins A and D in relation to immune cells and the clinical consequences of deficiencies in these important nutrients, especially in the perinatal period. Improved dietary uptake of iron is achieved by vitamin C, vitamin A, and whey compounds, whereas zinc bioavailability improves through citrates and proteins. The addition of oil is essential for the dietary uptake of beta-carotene and vitamin D. As for vitamin D, the major source comes via sun exposure and only a small amount is consumed via diet, which should be factored into clinical nutritional studies. We summarize the prevalence of micronutritional deficiencies of iron, zinc, and vitamins in the pediatric population as well as nutritional intervention studies on atopic diseases with whole food, food components, and micronutrients. Dietary uptake via the lymphatic route seems promising and is associated with a lower atopy risk and symptom amelioration. This review provides useful information for clinical studies and concludes/emphasizes that a healthy, varied diet containing dairy products, fish, nuts, fruits, and vegetables as well as supplementing foods or supplementation with micronutrients as needed is essential to combat the atopic march.

Maternal Diet Quality during Pregnancy and Allergic and Respiratory Multimorbidity Clusters in Children from the EDEN Mother-Child Cohort

We investigated the associations between maternal diet quality and allergic and respiratory diseases in children. Analyses were based on 1316 mother-child pairs from the EDEN mother-child cohort. Maternal diet quality during pregnancy was assessed through a food-based score (the Diet Quality), a nutrient-based score (the PANDiet), and the adherence to guidelines for main food groups. Clusters of allergic and respiratory multimorbidity clusters up to 8 years were identified using Latent Class Analysis. Associations were assessed by adjusted multinomial logistic regressions. Four clusters were identified for children: "asymptomatic" (67%, reference group), "asthma only" (14%), "allergies without asthma" (12%), "multi-allergic" (7%). These clusters were not associated with mother diet quality assessed by both scores. Children from mothers consuming legumes once a month or less were at higher risk of belonging to the "multi-allergic" cluster (odds ratio (OR) (95% confidence interval (95%CI)) = 1.60 (1.01;2.54)). No association was found with other food groups or other clusters. In our study, allergic and respiratory multimorbidity in children was described with four distinct clusters. Our results suggest an interest in legumes consumption in the prevention of allergic diseases but need to be confirmed in larger cohorts and randomized control trials.

Association of maternal low-carbohydrate-diet score during pregnancy with allergic diseases at 2 years of age

BACKGROUND

We prospectively evaluated the association between low-carbohydrate-diet (LCD) score during pregnancy and the risk of allergic diseases in infants up to 2 years.

METHODS

Participants were from a prospective mother-offspring cohort study in Wuhan, China. LCD score was calculated according to the percentage of dietary energy intake from carbohydrate, protein, and fat assessed in late pregnancy using validated food frequency questionnaires. Allergic diseases, including immunoglobulin E (IgE)-mediated allergic diseases, allergic contact dermatitis, and food allergy, were recorded at 3, 6, 12, and 24 months postpartum follow-up. Poisson regression models were used to calculate relative risks (RRs) and 95% confidence intervals (CIs).

RESULTS

Among 1636 mother-infant pairs included in the present analysis, 230 infants (14.1%) with IgE-mediated allergic diseases, 77 (4.7%) with allergic contact dermatitis, and 488 (29.8%) with food allergy were, respectively, reported. Independent of total energy intake and other potential confounders, both the lowest quintile (RR, 1.77; 95% CI, 1.13-2.77) and the highest quintile (RR, 1.72; 95% CI, 1.22-2.63), were associated with the risk of IgE-mediated allergic diseases compared with the middle quintile. Among high-carbohydrate-diet pregnant women, substituting 5% of energy from either protein or fat for carbohydrate was associated with a lower risk of IgE-mediated allergic diseases. While among low-carbohydrate-diet pregnant women, substituting 5% of energy from carbohydrate, especially high-quality carbohydrate, for fat was associated with a lower risk of IgE-mediated allergic diseases.

CONCLUSION

Maternal low carbohydrate-high protein and fat, and high carbohydrate-low protein and fat diet were both associated with an increased risk of allergic diseases in the infants up to 2 years. This study may provide an intervention strategy for allergy prevention in early childhood.

Asthma and the Missing Heritability Problem: Necessity for Multiomics Approaches in Determining Accurate Risk Profiles

Asthma is ranked among the most common chronic conditions and has become a significant public health issue due to the recent and rapid increase in its prevalence. Investigations into the underlying genetic factors predict a heritable component for its incidence, estimated between 35% and 90% of causation. Despite the application of large-scale genome-wide association studies (GWAS) and admixture mapping approaches, the proportion of variants identified accounts for less than 15% of the observed heritability of the disease. The discrepancy between the predicted heritable component of disease and the proportion of heritability mapped to the currently identified susceptibility loci has been termed the ‘missing heritability problem.’ Here, we examine recent studies involving both the analysis of genetically encoded features that contribute to asthma and also the role of non-encoded heritable characteristics, including epigenetic, environmental, and developmental aspects of disease. The importance of vertical maternal microbiome transfer and the influence of maternal immune factors on fetal conditioning in the inheritance of disease are also discussed. In order to highlight the broad array of biological inputs that contribute to the sum of heritable risk factors associated with allergic disease incidence that, together, contribute to the induction of a pro-atopic state. Currently, there is a need to develop in-depth models of asthma risk factors to overcome the limitations encountered in the interpretation of GWAS results in isolation, which have resulted in the missing heritability problem. Hence, multiomics analyses need to be established considering genetic, epigenetic, and functional data to create a true systems biology-based approach for analyzing the regulatory pathways that underlie the inheritance of asthma and to develop accurate risk profiles for disease.

Maternal Gut Microbiome Decelerates Fetal Endochondral Bone Formation by Inducing Inflammatory Reaction

To investigate the effect of the maternal gut microbiome on fetal endochondral bone formation, fetuses at embryonic day 18 were obtained from germ-free (GF) and specific-pathogen-free (SPF) pregnant mothers. Skeletal preparation of the fetuses’ whole bodies did not show significant morphological alterations; however, micro-CT analysis of the tibiae showed a lower bone volume fraction in the SPF tibia. Primary cultured chondrocytes from fetal SPF rib cages showed a lower cell proliferation and lower accumulation of the extracellular matrix. RNA-sequencing analysis showed the induction of inflammation-associated genes such as the interleukin (IL) 17 receptor, IL 6, and immune-response genes in SPF chondrocytes. These data indicate that the maternal gut microbiome in SPF mice affects fetal embryonic endochondral ossification, possibly by changing the expression of genes related to inflammation and the immune response in fetal cartilage. The gut microbiome may modify endochondral ossification in the fetal chondrocytes passing through the placenta.

The Role of Diet and Gut Microbiota in Regulating Gastrointestinal and Inflammatory Disease

Diet is an important lifestyle factor that is known to contribute in the development of human disease. It is well established that poor diet plays an active role in exacerbating metabolic diseases, such as obesity, diabetes and hypertension. Our understanding of how the immune system drives chronic inflammation and disease pathogenesis has evolved in recent years. However, the contribution of dietary factors to inflammatory conditions such as inflammatory bowel disease, multiple sclerosis and arthritis remain poorly defined. A western diet has been associated as pro-inflammatory, in contrast to traditional dietary patterns that are associated as being anti-inflammatory. This may be due to direct effects of nutrients on immune cell function. Diet may also affect the composition and function of gut microbiota, which consequently affects immunity. In animal models of inflammatory disease, diet may modulate inflammation in the gastrointestinal tract and in other peripheral sites. Despite limitations of animal models, there is now emerging evidence to show that anti-inflammatory effects of diet may translate to human gastrointestinal and inflammatory diseases. However, appropriately designed, larger clinical studies must be conducted to confirm the therapeutic benefit of dietary therapy.

Food Protein-Induced Allergic Proctocolitis: The Effect of Maternal Diet During Pregnancy and Breastfeeding in a Mediterranean Population

Background

The aim of the current investigation was to explore the association of food protein-induced allergic proctocolitis (FPIAP) with the maternal diet during pregnancy and breastfeeding in Greek infants.

Methods

A multicenter retrospective case-control study was conducted in 6 regions in Greece, with 96 mothers of infants with and 141 mothers of infants without a history of FPIAP. Maternal dietary habits during pregnancy and breastfeeding were evaluated with the following validated questionnaires: (a) The Mediterranean Diet Score and (b) The Mediterranean Oriented Culture-Specific Semi-Quantitative Food Frequency Questionnaire.

Results

FPIAP was associated with cow's milk (83.6%), egg (7.3%), wheat (6.4%), and beef (6.4%) in the maternal diet. Adherence to Mediterranean Diet was similar among the mothers. Mothers of FPIAP infants consumed more vegetables. Elastic net prediction models showed that, in this Mediterranean population, increased consumption during pregnancy and lactation of common allergens, whole grain products, homemade food, fish and shellfish, and fruits was associated with a decreased risk of FPIAP. Conversely, a high intake of vegetables, sugar and total fat, and non-stick/grilled cooking, were associated with increased risk of FPIAP, as was a high intake of salt and white flour during lactation only.

Conclusions

Components of a maternal Mediterranean Diet may protect against FPIAP when traditional cooking methods are adopted and fish, fruit, and whole wheat products are consumed frequently during pregnancy and breastfeeding.

Primary Prevention of Pediatric Asthma through Nutritional Interventions

Asthma is the most common chronic non-communicable disease in children, the pathogenesis of which involves several factors. The increasing burden of asthma worldwide has emphasized the need to identify the modifiable factors associated with the development of the disease. Recent research has focused on the relationship between dietary factors during the first 1000 days of life (including pregnancy)—when the immune system is particularly vulnerable to exogenous interferences—and allergic outcomes in children. Specific nutrients have been analyzed as potential targets for the prevention of childhood wheeze and asthma. Recent randomized controlled trials show that vitamin D supplementation during pregnancy, using higher doses than currently recommended, may be protective against early childhood wheezing but not school-age asthma. Omega-3 fatty acid supplementation during pregnancy and infancy may be associated with a reduced risk of childhood wheeze, although the evidence is conflicting. Data from observational studies suggest that some dietary patterns during pregnancy and infancy might also influence the risk of childhood asthma. However, the quality of the available evidence is insufficient to allow recommendations regarding dietary changes for the prevention of pediatric asthma. This review outlines the available high-quality evidence on the role of prenatal and perinatal nutritional interventions for the primary prevention of asthma in children and attempts to address unmet areas for future research in pediatric asthma prevention.

Proportions of Polyunsaturated Fatty Acids in Umbilical Cord Blood at Birth Are Related to Atopic Eczema Development in the First Year of Life

Atopic eczema, the most common atopic disease in infants, may pave the way for sensitization and allergy later in childhood. Fatty acids have immune-regulating properties and may regulate skin permeability. Here we examine whether the proportions of fatty acids among the infant and maternal plasma phospholipids at birth were associated with maternal dietary intake during pregnancy and development of atopic eczema during the first year of age in the Nutritional impact on Immunological maturation during Childhood in relation to the Environment (NICE) birth cohort. Dietary data were collected with a semi-quantitative food frequency questionnaire, fatty acids were measured with GC-MS and atopic eczema was diagnosed by a pediatric allergologist at 12 months of age. We found that higher proportions of n-6 PUFAs (including arachidonic acid) but lower proportions of n-3 PUFAs (including DPA) in the infant’s phospholipids at birth were associated with an increased risk of atopic eczema at 12 months of age. The n-6 and n-3 PUFAs were related to maternal intake of meat and fish, respectively. Our results suggest that prenatal exposure to unsaturated fatty acids is associated with eczema development in the infant. Maternal diet during pregnancy may partly explain the fatty acid profiles in utero.

Genes, environment, and developmental timing: New insights from translational approaches to understand early origins of respiratory diseases

Over the past decade, "omics" approaches have advanced our understanding of the molecular programming of the airways in humans. Several studies have identified potential molecular mechanisms that contribute to early life epigenetic reprogramming, including DNA methylation, histone modifications, microRNAs, and the homeostasis of the respiratory mucosa (epithelial function and microbiota). Current evidence supports the notion that early infancy is characterized by heightened susceptibility to airway genetic reprogramming in response to the first exposures in life, some of which can have life-long consequences. Here, we summarize and analyze the latest insights from studies that support a novel epigenetic paradigm centered on human maturational and developmental programs including three cardinal elements: genes, environment, and developmental timing. The combination of these factors is likely responsible for the functional trajectory of the respiratory system at the molecular, functional, and clinical levels.

Fish consumption during pregnancy and risk of allergic diseases in the offspring: A systematic review and meta-analysis

Although several studies have reported the beneficial effects of maternal fish consumption on allergy diseases in the offspring, the findings are conflicting. We summarized earlier data on the association between maternal fish intake and risk of allergy diseases in the offspring through a meta-analysis. A systematic literature search of relevant reports published in Medline/PubMed, ISI web of Science, EMBASE, SCOPUS and Google Scholar prior to February 2020 was conducted. All observational studies (cross-sectional, case-control or cohort) that examined the relationship between intake of maternal fish and risk of allergy diseases in the offspring were considered. Duplicate and non-related studies were excluded. In total, 31 studies on maternal fish consumption and risk of allergic diseases in the offspring were included. Greater maternal fish intake was associated with a reduced risk of wheeze (Pooled effect size: 0.97; 95% CI: 0.96-0.99) and food allergy (0.75; 95% CI: 0.64-0.88). Maternal fish consumption was not associated with risk of asthma (pooled effect size: 0.99; 95% CI: 0.89, 1.11), eczema (pooled effect size: 0.93; 95% CI: 0.84, 1.03), allergic rhinitis (pooled effect size: 0.91; 95% CI: 0.75, 1.09), and inhalant allergy (pooled effect size: 0.86; 95% CI: 0.66, 1.13). In non-linear dose-response meta-analysis, increased intake of fish during pregnancy (at the level of 50 to 200 grams per week) was associated with a reduced risk of eczema (P non-linearity = 0.042). Meta-regression of included studies revealed an inverse linear association between maternal fish intake and risk of eczema; such that every additional 30-gram per week consumption of fish during pregnancy was associated with a 4% reduced risk of eczema. We found that fish intake during pregnancy was associated with a lower risk of wheeze, eczema and food allergy in children. No significant association was seen between maternal fish consumption and risk of offspring's asthma, allergic rhinitis, and inhalant allergy.

Dietary Fat and Fatty Acid Intake in Nulliparous Women: Associations with Preterm Birth and Distinctions by Maternal BMI

BACKGROUND

Evidence documenting whether diet quality, particularly dietary fatty acids, is associated with preterm birth (PTB) is limited.

OBJECTIVE

The aim was to measure associations between dietary fatty acid intake prior to pregnancy, specifically n-3 (ɷ-3) PUFAs and odds of PTB in US women and determine if associations differed by prepregnancy BMI.

METHODS

We designed a secondary analysis of dietary intake in nulliparous women enrolled in a longitudinal cohort (NCT01322529). Participants completed an FFQ, modified to assess detailed PUFA intake, during the 3 mo preceding pregnancy. Inclusion in this analytic cohort required total energy intake within 2 SDs of the group mean. Prepregnancy BMI was categorized as underweight, normal, overweight, or obese. The primary exposure was estimated intake of EPA and DHA (combined EPA+DHA), in the context of a recommended intake of 250 mg. The primary outcome was PTB (<37 wk). Adjusted regression models controlled for maternal factors relevant to PTB and evaluated associations with PUFAs. Interaction terms estimated effect modification of BMI. A false discovery rate (FDR) correction accounted for multiple comparisons.

RESULTS

Median daily intake of combined EPA+DHA in 7365 women was 70 mg (IQR: 32, 145 mg). A significant interaction term indicated the effects of EPA+DHA on odds of PTB were different for different BMI categories (P < 0.01). Specifically, higher intake of combined EPA+DHA was nominally associated with reduced odds of PTB in women with underweight (OR: 0.67; 95% CI: 0.46-0.98) and normal BMI (OR: 0.87; 95% CI: 0.78-0.96), yet was associated with increased odds of overweight BMI (OR: 1.21; 95% CI: 1.02-1.44). Associations remained significant after FDR correction.

CONCLUSIONS

Based on a cohort of US women designed to identify predictors of adverse pregnancy outcomes, dietary intake of combined EPA+DHA was considerably lower than recommended. Associations between intake of these recommended n-3 fatty acids and risk of PTB differ by maternal BMI.

Insights into allergic risk factors from birth cohort studies

OBJECTIVE

To present an update of birth cohort study designs and their contributions to allergic risk.

DATA SOURCES

The PubMed database was used to search for relevant articles.

STUDY SELECTIONS

Peer-reviewed prospective and retrospective studies involving the assessment of allergy using human birth cohorts between 2014 and 2021 were evaluated.

RESULTS

Parental history of allergic diseases, especially in cases involving both parents, is associated with increased risk of allergy. Exposure to prenatal and postnatal smoking and limited diet diversity were associated with increased allergic burden. The impact of early-life infections and antibiotics on disease development may be associated with the onset of asthma, though this remains debated. Cohort studies also revealed that the mode of delivery and breastfeeding duration affect the odds ratio of asthma and eczema development. Household exposures, including pets, house dust mites, and scented aeroallergens may confer protective effects, whereas high air pollution exposure and low socioeconomic status may be risk enhancing. Exposure to antibiotics during early life may be associated with increased asthma risk, whereas viral infections may lead to disease protection, though the impact of the coronavirus disease 2019 pandemic on allergic risk is yet to be understood.

CONCLUSION

Although evaluating the risk of allergic disease development is complex, clinicians can apply these insights on the multifactorial nature of atopy to better understand and potentially mitigate disease development.

An integrative medicine review of primary prevention of allergy in pediatrics

The prevalence of allergic disease has been rapidly increasing in the developed world for over fifty years. The prevention of allergic disease remains one of the most elusive topics in medicine. Integrative medicine emphasizes prevention of disease and utilizes many interventions to help modify long-term outcomes of health. Primary prevention refers to the arrest of manifestations of a disease before they present clinically. Preventing allergy is not simply about preventing sensitization, but also about developing tolerance. This narrative review article will discuss integrative medicine approaches that may help to prevent atopic disease in the pediatric population. It is organized chronologically to aid in counseling patients: 1) prevention during pregnancy and 2) prevention after birth. While research into allergy prevention is in its infancy, Integrative Medicine is well-suited to provide many insights into the prevention and mitigation of atopic disease.

Nuclear Receptors in Asthma: Empowering Classical Molecules Against a Contemporary Ailment

The escalation in living standards and adoption of 'Western lifestyle' has an allied effect on the increased allergy and asthma burden in both developed and developing countries. Current scientific reports bespeak an association between allergic diseases and metabolic dysfunction; hinting toward the critical requirement of organized lifestyle and dietary habits. The ubiquitous nuclear receptors (NRs) translate metabolic stimuli into gene regulatory signals, integrating diet inflences to overall developmental and physiological processes. As a consequence of such promising attributes, nuclear receptors have historically been at the cutting edge of pharmacy world. This review discusses the recent findings that feature the cardinal importance of nuclear receptors and how they can be instrumental in modulating current asthma pharmacology. Further, it highlights a possible future employment of therapy involving dietary supplements and synthetic ligands that would engage NRs and aid in eliminating both asthma and linked comorbidities. Therefore, uncovering new and evolving roles through analysis of genomic changes would represent a feasible approach in both prevention and alleviation of asthma.

Umbilical cord blood metabolome differs in relation to delivery mode, birth order and sex, maternal diet and possibly future allergy development in rural children

Allergy is one of the most common diseases among young children yet all factors that affect development of allergy remain unclear. In a small cohort of 65 children living in the same rural area of south-west Sweden, we have previously found that maternal factors, including prenatal diet, affect childhood allergy risk, suggesting that in utero conditions may be important for allergy development. Here, we studied if metabolites in the umbilical cord blood of newborns may be related to development of childhood allergy, accounting for key perinatal factors such as mode of delivery, birth order and sex. Available umbilical cord blood plasma samples from 44 of the participants were analysed using gas chromatography-mass spectrometry metabolomics; allergy was diagnosed by specialised paediatricians at ages 18 months, 3 years and 8 years and included eczema, asthma, food allergy and allergic rhinoconjunctivitis. Nineteen cord blood metabolites were related to future allergy diagnosis though there was no clear pattern of up- or downregulation of metabolic pathways. In contrast, perinatal factors birth order, sex and mode of delivery affected several energy and biosynthetic pathways, including glutamate and aspartic acid—histidine metabolism (p = 0.004) and the tricarboxylic acid cycle (p = 0.006) for birth order; branched chain amino acid metabolism (p = 0.0009) and vitamin B₆ metabolism (p = 0.01) for sex; and glyoxylate and dicarboxylic acid metabolism (p = 0.005) for mode of delivery. Maternal diet was also related to some of the metabolites associated with allergy. In conclusion, the cord blood metabolome includes individual metabolites that reflect lifestyle, microbial and other factors that may be associated with future allergy diagnosis, and also reflects temporally close events/factors. Larger studies are required to confirm these associations, and perinatal factors such as birth order or siblings must be considered in future cord-blood metabolome studies.

Does antioxidant-rich diet during pregnancy protect against atopic multimorbidity in children?

BACKGROUND

Genetics and prenatal environmental exposures are indicated in the complex etiopathogenesis and clinical expression of atopic diseases. This study examined the clinical features of infantile-onset atopic dermatitis (AD) in relation to maternal diet during pregnancy.

METHODS

Maternal dietary habits were evaluated in terms of the frequency of intake of six different food categories rich in antioxidants or omega-3 fatty acids.

RESULTS

One hundred mother-child pairs were recruited, 47 infants (<12 months) and 53 children aged 12-36 months. Forty-six of the children had mild, 41 moderate and 13 severe AD. The other atopic manifestations (alone or associated) included: asthma in 9 cases, allergic rhinitis in 22 cases and food allergy in 33 cases. The presence of asthma in children was significantly associated with a lower level of maternal dietary intake of fruits and vegetables as well as chocolate confectionery, while associations with whole grain breakfast cereals, nuts and seeds, non-alcoholic beverages (coffee, tea, fruit juices) and fish and fish products, were not statistically significant. The age of onset and severity of infantile-onset AD were not linked to any of the food categories considered for analyses.

CONCLUSIONS

Healthy diet in pregnant women that is rich especially in antioxidants may provide protection against atopic comorbidities of AD. Further prospective reasearch on the role of maternal diet in primary prevention of atopic diseases is warranted.

Maternal age at delivery and risk of allergy and asthma in the offspring: a systematic review and meta-analysis protocol

INTRODUCTION

While several perinatal factors have been linked to the risk of developing asthma and allergy in childhood, the role of maternal age at delivery remains uncertain. Some studies suggest that young maternal age at delivery may increase the risk, while other studies suggested a reduced risk. To provide a clearer appreciation of the underlying evidence, we plan to undertake a systematic review to synthesise previous studies that have investigated the association between maternal age at delivery and the risk of asthma and allergy in the offspring.

METHODS AND ANALYSIS

We will search PubMed, EMBASE, ISI Web of Science, Scopus and Google Scholar to identify relevant studies on the topic published in the databases from inception until October 2020. We will search databases of proceedings of international conferences, contact authors who have published on the topic and search the reference lists of the included studies in order to identify additional studies. Two investigators will independently screen the identified studies, perform data extraction and examine the risk of bias in the studies; a third investigator will arbitrate throughout these processes. We will use the Effective Public Health Practice Project tool for assessment of the risk of bias in included studies. We will perform random-effects meta-analysis to combine effect estimates from included studies judged to be homogeneous.

ETHICS AND DISSEMINATION

Only data from the published literature will be included in this study, therefore no ethics approval is required. Our findings will be published in a peer-reviewed journal.

PROTOCOL REGISTRATION

The protocol has been submitted for registration on PROSPERO, University of York, and Centre for Review and Dissemination, now awaiting the assignment of a registration number.

Gestational Dysfunction-Driven Diets and Probiotic Supplementation Correlate with the Profile of Allergen-Specific Antibodies in the Serum of Allergy Sufferers

BACKGROUND

Maternal diet has significant effects on development of childhood atopic disease and hypersensitivity development. However, the gestational dysfunctions demanding special diets are becoming a widespread phenomenon, their immunological implications can be manifested in the profile of antibodies in the offspring's serum.

METHODS

153 allergic and 150 healthy individuals were diagnosed for allergy using specific antibody and cytokine immunoassay tests. The medical history of subjects along with mothers' course of pregnancy was completed by allergologist's anamnesis. A self-organizing neural network and multivariate analyses to complex data and pick basic interactions were used.

RESULTS

Two significant explanatory modules were determined. The first was formed by gestational diabetic and cholestatic diet, infant formula feeding type, probiotic supplementation and its BMI index, moderate IgE, increased IgG levels of antibodies and single or poly-food allergy type (7 clusters). The second was formed by gestational vegan/vegetarian and elimination diet, maternal probiotic supplementation, sex, high IgE total antibodies and food and mixed poly-allergy to aero- and food-origin allergens (19 clusters).

CONCLUSIONS

Significant associations were observed between special gestational diet intake underlying foetal programming and the mechanisms of childhood allergy. The novelty is the positive association between diabetic and cholestatic diet intake and IgE/IgG-mediated food hypersensitivity.

Benefits of Adhering to a Mediterranean Diet Supplemented with Extra Virgin Olive Oil and Pistachios in Pregnancy on the Health of Offspring at 2 Years of Age. Results of the San Carlos Gestational Diabetes Mellitus Prevention Study

The intrauterine environment may be related to the future development of chronic diseases in the offspring. The St. Carlos gestational diabetes mellitus (GDM) prevention study, is a randomized controlled trial that evaluated the influence of the early (before 12th gestational week) Mediterranean diet (MedDiet) on the onset of GDM and adverse gestational outcomes. Out of 874 women assessed after delivery (440 control group (CG)/434 intervention group (IG)), 703 children were followed (365/338; CG/IG), with the aim to assess whether the adherence to a MedDiet during pregnancy induces health benefits for the offspring during the first two years of life. Logistic regression analysis showed that the IG in children of mothers with pre-gestational body mass index (BMI) < 25 kg/m² and normal glucose tolerance (NGT), was associated with a lower risk (RR(95% CI)) of suffering from severe events requiring hospitalization due to bronchiolitis/asthma (0.75(0.58–0.98) and 0.77(0.59–0.99), respectively) or other diseases that required either antibiotic (0.80(0.65–0.98) and 0.80(0.65–0.99), respectively), corticosteroid treatment (0.73(0.59–0.90) and 0.79(0.62–1.00) respectively) or both (all p < 0.05). A nutritional intervention based on the MedDiet during pregnancy is associated with a reduction in offspring’s hospital admissions, especially in women with pre-gestational BMI < 25 kg/m² and NGT.

Nutritional Factors in the Prevention of Atopic Dermatitis in Children

Atopic dermatitis is one of the most frequent chronic skin diseases worldwide and often develops within the first few years of life. Recent advancements in our knowledge of its pathophysiology have brought to light the role of genetic predisposition and environmental triggers. With the increasing prevalence of allergic diseases, there is a strong need for a better understanding of the various modifiable eliciting factors of such conditions. The concomitant rise in food allergy and insights into the skin barrier function has highlighted the role of nutrition and diet in the prevention and modification of allergic disorders. Furthermore, the identification of the skin as an important route of sensitization, and the risk of progression to asthma later in life, stress the significance of optimizing our management of skin inflammation in the prevention of allergies. Many nutritional factors, including the type of maternal diet during pregnancy, the duration of breastfeeding, the epicutaneous exposure of allergenic food proteins in the first few years of life, the timing of the introduction of complementary foods, the supplementation of vitamins and probiotics/prebiotics during prenatal and early life, have been assessed as potential targets for the prevention of atopy and eczema. Here, we review the latest data addressing prenatal and perinatal nutritional and dietary interventions in the primary prevention of atopic dermatitis. Also, we define knowledge gaps and targets for future research in the prevention of atopic dermatitis.

Current Insights on Early Life Nutrition and Prevention of Allergy

The incidence of allergic diseases in childhood appears to have significantly increased over the last decades. Since environmental factors, including diet, have been thought to play a significant role in the development of these diseases, there is great interest in identifying prevention strategies related to early nutritional interventions. Breastfeeding is critical for the immune development of newborns and infants through immune-modulating properties and it impacts the establishment of a healthy gut microbiota. However, the evidence for a protective role of breastfeeding against the development of food allergy in childhood is controversial, and there is little evidence to support the benefits of an antigen avoidance diet during lactation. Although it is not possible to draw a definitive conclusion about the protective role of breast milk against allergic diseases, exclusive breastfeeding is still recommended throughout the first 6 months of life due to associated health benefits. Furthermore, recommendations regarding complementary feeding in infancy have been significantly modified over the last few decades. Several studies have shown that delayed exposure to allergenic foods does not have a role in allergy prevention and recent guidelines recommend against delaying the introduction of complementary foods after 6 months of age, both in high- and low-risk infants. However, trials investigating this dietary approach have reported equivocal results so far. This review summarizes the available high-quality evidence regarding the efficacy of the principal dietary interventions proposed in early life to prevent allergic diseases in children.

Dietary Interventions and Nutritional Factors in the Prevention of Pediatric Asthma

Asthma is the most frequent chronic disease in children, and its pathogenesis involves genetic, epigenetic, and environmental factors. The rapid rise in the prevalence of asthma registered over the last few decades has stressed the need to identify the environmental and modifiable factors associated with the development of the disease. In particular, there is increasing interest in the role of modifiable nutritional factors specific to both the prenatal and post-natal early life as, during this time, the immune system is particularly vulnerable to exogenous interferences. Several dietary factors, including maternal diet during pregnancy, the duration of breastfeeding, the use of special milk formulas, the timing of the introduction of complementary foods, and prenatal and early life supplementation with vitamins and probiotics/prebiotics, have been addressed as potential targets for the prevention of asthma. In this review, we outline recent findings on the potential role of prenatal and perinatal dietary and nutritional interventions for the primary prevention of pediatric asthma. Moreover, we addressed unmet needs and areas for future research in the prevention of childhood-onset asthma.

Pre-pregnancy Maternal Weight and Gestational Weight Gain Increase the Risk for Childhood Asthma and Wheeze: An Updated Meta-Analysis

Background: Mounting evidence suggests that childhood asthma is closely associated with maternal weight before pregnancy and gestational weight gain (GWG), yet the results are not often reproducible. Objectives: We conducted a comprehensive meta-analysis, aiming to evaluate the association of pre-pregnancy maternal obesity or overweight and high GWG with the risk for childhood asthma and wheeze. Methods: Literature search, quality assessment, and data extraction were completed independently and in duplicate. Effect-size estimates are expressed as odds ratio (OR) with 95% confidence interval (CI). Results: Twenty-two observational studies involving 145,574 mother-child pairs were meta-analyzed. In overall analyses, maternal obesity or overweight in pre-pregnancy significantly increased the risk of both childhood asthma and wheeze (adjusted OR: 1.41 and 1.13, 95% CI: 1.26-1.59 and 1.07-1.20, both p < 0.001). Per 1 kg/m² increment in maternal body mass index was associated with a significantly increased risk of childhood asthma and wheeze (adjusted OR: 1.03, 95% CI: 1.02-1.03, p < 0.001). Compared with normal GWG, very high GWG (adjusted OR: 1.24, 95% CI: 1.04-1.47, p: 0.018), moderate high GWG (adjusted OR: 1.12, 95% CI: 1.04-1.21, p: 0.004), and very low GWG (adjusted OR: 1.26, 95% CI: 1.08-1.47, p: 0.004) increased the risk of childhood asthma and wheeze. There was a low probability of publication bias. Conclusions: Our findings indicate that both pre-pregnancy maternal obesity or overweight and very to moderate high or low GWG render their offspring susceptible to a significantly increased risk of having childhood asthma and wheeze.

Pre-Conception Maternal Food Intake and the Association with Childhood Allergies

BACKGROUND

Periconceptional nutrition may have an important function in programming the immune function and allergies, however, there is a lack of studies assessing pre-conception food intake and childhood allergic disorders. The aim of the current study was to identify maternal pre-conception dietary components that may be associated with allergic disorders in children up to 3 years of age.

METHODS

Pregnant women attending their first antenatal visit and who were aged >18 years were invited to participate. Pre-conception food frequency data was retrospectively collected at 18 weeks' gestation. Childhood eczema, current wheeze, and rhinitis was assessed at 36 months of age using a questionnaire and doctor diagnosis (n = 234). Linear discriminant analysis (LDA) was used to explore the combination of dietary food components that best discriminated between allergy status in children.

RESULTS

Maternal pre-conception food intake such as low and high fat dairy, fresh fruit, unsaturated spreads, and take-away foods, were protective for any allergy assessed. Non-oily fish was protective for eczema and current wheeze; saturated spreads (e.g., butter) was protective for eczema, current wheeze, and rhinitis; poultry and fruit juice were adversely associated with each allergy.

CONCLUSIONS

Pre-conception food intakes demonstrate inconsistent and somewhat contrary relationships to the development of child allergies. Whether and how maternal food intake impacts the underlying fetal programming and the mechanisms of childhood allergy warrants further investigation.