Cesarean delivery is associated with celiac disease but not inflammatory bowel disease in children

Antibiotics, passive smoking, high socioeconomic status and sweetened foods contribute to the risk of paediatric inflammatory bowel disease: A systematic review with meta-analysis

OBJECTIVE

Genetic and environmental factors influence pathogenesis and rising incidence of paediatric inflammatory bowel disease (PIBD). The aim was to meta-analyse evidence of diet and environmental factors in PIBD.

METHODS

A systematic search was conducted to identify diet and environmental factors with comparable risk outcome measures and had been reported in two or more PIBD studies for inclusion in meta-analyses. Those with ≥2 PIBD risk estimates were combined to provide pooled risk estimates.

RESULTS

Of 4763 studies identified, 36 studies were included. PIBD was associated with higher risk with exposure to ≥/=4 antibiotic courses (includes prescriptions/purchases/courses), passive smoking, not being breastfed, sugary drink intake, being a non-Caucasian child living in a high-income country and infection history (odds ratio [OR] range: 2-3.8). Paediatric Crohn's disease (CD) was associated with higher risk with exposure to antibiotics during early childhood, ≥/=4 antibiotic courses, high socioeconomic status (SES), maternal smoking, history of atopic conditions and infection history (OR range: 1.6-4.4). A history of infection was also associated with higher risk of paediatric ulcerative colitis (UC) (OR: 3.73). Having a higher number of siblings (≥2) was associated with lower risk of paediatric CD (OR: 0.6) and paediatric UC (OR: 0.7). Pet exposure was associated with lower risk of paediatric UC (OR: 0.5).

CONCLUSION

Several factors associated with PIBD risk were identified that could potentially be used to develop a disease screening tool. Future research is needed to address risk reduction in PIBD.

Changes in DNA methylation associated with a specific mode of delivery: a pilot study

Background

The mode of delivery represents an epigenetic factor with potential to affect further development of the individual by multiple mechanisms. DNA methylation may be one of them, representing a major epigenetic mechanism involving direct chemical modification of the individual's DNA. This pilot study aims to examine whether a specific mode of delivery induces changes of DNA methylation by comparing the umbilical cord blood and peripheral blood of the newborns.

Methods

Blood samples from infants born by vaginal delivery and caesarean section were analysed to prepare the Methylseq library according to NEBNext enzymatic Methyl-seq Methylation Library Preparation Kit with further generation of target-enriched DNA libraries using the Twist Human Methylome Panel. DNA methylation status was determined using Illumina next-generation sequencing (NGS).

Results

We identified 168 differentially methylated regions in umbilical cord blood samples and 157 regions in peripheral blood samples. These were associated with 59 common biological, metabolic and signalling pathways for umbilical cord and peripheral blood samples.

Conclusion

Caesarean section is likely to represent an important epigenetic factor with the potential to induce changes in the genome that could play an important role in development of a broad spectrum of disorders. Our results could contribute to the elucidation of how epigenetic factors, such as a specific mode of delivery, could have adverse impact on health of an individual later in their life.

An Overview of the Influence of Breastfeeding on the Development of Inflammatory Bowel Disease

The first 1000 days of life is a critical period that contributes significantly to the programming of an individual's future health. Among the many changes that occur during this period early in life, there is growing evidence that the establishment of healthy gut microbiota plays an important role in the prevention of both short- and long-term health problems. Numerous publications suggest that the quality of the gut microbiota colonisation depends on several dietary factors, including breastfeeding. In this respect, a relationship between breastfeeding and the risk of inflammatory bowel disease (IBD) has been suggested. IBDs are chronic intestinal diseases, and perinatal factors may be partly responsible for their onset. We review the existence of links between breastfeeding and IBD based on experimental and clinical studies. Overall, despite encouraging experimental data in rodents, the association between breastfeeding and the development of IBD remains controversial in humans, partly due to the considerable heterogeneity between clinical studies. The duration of exclusive breastfeeding is probably decisive for its lasting effect on IBD. Thus, specific improvements in our knowledge could support dietary interventions targeting the gut microbiome, such as the early use of prebiotics, probiotics or postbiotics, in order to prevent the disease.

Relationship between gluten availability and celiac disease prevalence: A geo-epidemiologic systematic review

Celiac disease is a global disease requiring genetic susceptibility and gluten exposure to trigger immune-mediated enteropathy. The effect of the degree of gluten-containing grain availability on celiac disease prevalence is unknown. Our objective was to compare country-based gluten availability to celiac prevalence using a systematic literature review. We searched MEDLINE, Embase, Cochrane, and Scopus until May 2021. We included population-based serum screening with confirmatory testing (second serological study or small intestine biopsy) and excluded specific, high-risk, or referral populations. We determined country-specific gluten availability using the United Nations food balance for wheat, barley, and rye. Human leukocyte antigen (HLA) frequencies were obtained from allelefrequencies.net. The primary outcome was association between gluten-containing grain availability and celiac disease prevalence. Generalized linear mixed models method with Poisson's link was used for analysis. We identified 5641 articles and included 120 studies on 427 146 subjects from 41 countries. Celiac disease prevalence was 0-3.1%, median 0.75% (interquartile range 0.35, 1.22). Median wheat supply was 246 g/capita/day (interquartile range 214.8, 360.7). The risk ratio (RR) for wheat availability on celiac disease was 1.002 (95% confidence interval [CI]: 1.0001, 1.004, P = 0.036). A protective association was seen with barley, RR 0.973 (95% CI: 0.956, 0.99, P = 0.003), and rye, RR 0.989 (95% CI: 0.982, 0.997, P = 0.006). The RR for gross domestic product on celiac disease prevalence was 1.009 (95% CI: 1.005, 1.014, P < 0.001). The RR for HLA-DQ2 was 0.982 (95% CI: 0.979, 0.986, P < 0.001), and that for HLA-DQ8 was 0.957 (95% CI: 0.950, 0.964, P < 0.001). In this geo-epidemiologic study, gluten-containing grain availability showed mixed associations with celiac disease prevalence.

Microbiome analysis of maternal and neonatal microbial communities associated with the different delivery modes based on 16S rRNA gene amplicon sequencing

OBJECTIVE

With the rising number of cases of non-vaginal delivery worldwide, scientists have been concerned about the influence of the different delivery modes on maternal and neonatal microbiomes. Although the birth rate trend is decreasing rapidly in Taiwan, more than 30 percent of newborns are delivered by caesarean section every year. However, it remains unclear whether the different delivery modes could have a certain impact on the postpartum maternal microbiome and whether it affects the mother-to-newborn vertical transmission of bacteria at birth.

MATERIALS AND METHODS

To address this, we recruited 30 mother-newborn pairs to participate in this study, including 23 pairs of vaginal delivery (VD) and seven pairs of caesarean section (CS). We here investigate the development of the maternal prenatal and postnatal microbiomes across multiple body habitats. Moreover, we also explore the early acquisition of neonatal gut microbiome through a vertical multi-body site microbiome analysis.

RESULTS AND CONCLUSION

The results indicate that no matter the delivery mode, it only slightly affects the maternal microbiome in multiple body habitats from pregnancy to postpartum. On the other hand, about 95% of species in the meconium microbiome were derived from one of the maternal body habitats; notably, the infants born by caesarean section acquire bacterial communities resembling their mother's oral microbiome. Consequently, the delivery modes play a crucial role in the initial colonization of the neonatal gut microbiome, potentially impacting children's health and development.

Microbiota revolution: How gut microbes regulate our lives

The human intestine is a natural environment ecosystem of a complex of diversified and dynamic microorganisms, determined through a process of competition and natural selection during life. Those intestinal microorganisms called microbiota and are involved in a variety of mechanisms of the organism, they interact with the host and therefore are in contact with the organs of the various systems. However, they play a crucial role in maintaining host homeostasis, also influencing its behaviour. Thus, microorganisms perform a series of biological functions important for human well-being. The host provides the microorganisms with the environment and nutrients, simultaneously drawing many benefits such as their contribution to metabolic, trophic, immunological, and other functions. For these reasons it has been reported that its quantitative and qualitative composition can play a protective or harmful role on the host health. Therefore, a dysbiosis can lead to an association of unfavourable factors which lead to a dysregulation of the physiological processes of homeostasis. Thus, it has pre-viously noted that the gut microbiota can participate in the pathogenesis of autoimmune diseases, chronic intestinal inflammation, diabetes mellitus, obesity and atherosclerosis, neurological disorders (e.g., neurological diseases, autism, etc.) colorectal cancer, and more.

Interaction between Gut Microbiota and Celiac Disease: From Pathogenesis to Treatment

Celiac disease (CD) is a common systemic disorder that results from an abnormal response of human immunity to gluten intake, affecting the small intestine. In individuals who carry a genetic susceptibility, CD is triggered by environmental factors, including viral infections and dysbiosis of the gut microbiota. The gut microbiome is essential in controlling the immune system, and recent findings indicate that changes in the gut microbiome may contribute to various chronic immune disorders, such as CD through mechanisms that still require further exploration. Some bacteria exhibit epitopes that mimic gliadin and may enhance an immune response in the host. Other bacteria, including Pseudomonas aeruginosa, may work in conjunction with gluten to trigger and escalate intestinal inflammation. The microbiota may also directly influence antigen development through the production of immunogenic or tolerogenic gluten peptides or directly influence intestinal permeability through the release of zonulin. Finally, the gut microbiome can impact intestinal inflammation by generating proinflammatory or anti-inflammatory cytokines and metabolites. It is crucial to consider the impact of genetic factors (specifically, HLA-DQ haplotypes), perinatal elements such as birth mode, type of infant feeding, and antibiotic and infection exposure on the composition of the early intestinal microbiome. According to the available studies, the gut microbiome alterations associated with CD tend to exhibit a decreased presence of beneficial bacteria, including some anti-inflammatory Bifidobacterium species. However, some controversy remains as some reports have found no significant differences between the gut microbiomes of individuals with and without CD. A better understanding of the gut microbiome’s role in the development of CD would greatly benefit both prevention and treatment efforts, especially in complicated or treatment-resistant cases. Here, we have attempted to summarize the available evidence on the relationship between the gut microbiota and CD, with a particular focus on potential therapeutic targets.

Overweight and Obesity in Adult Birth by Cesarean Section: A Systematic Review With Meta-analysis

CONTEXT

Overweight/obesity is one of the most important health problems. Birth by cesarean section has been shown to influence long-term health outcomes including obesity.

OBJECTIVE

The aim of this systematic review-meta-analysis is to update acknowledgment of the increased risk of cesarean section on offspring's overweight/obesity.

METHODS

This study follows the PRISMA guidelines. A systematic literature search was conducted on Scopus, PubMed, and Web of Science; we have selected all the articles published until January 2, 2022. For inclusion, studies must have reported either (i) both birth by cesarean section and adult (≥18 years) offspring's body mass index; (ii) cohort or case-control study design; and (iii) a risk estimate. Heterogeneity testing was performed using Cochran's Q and I2 statistics. Publication bias was assessed by the Egger test and the Begg test. Meta-analysis was performed through a random-effects model.

RESULTS

Twelve studies with a combined population of 180 065 subjects were included in the meta-analysis. The overall analysis (N = 19) yielded a combined risk estimate for overweight/obesity of 1.19 (95% CI, 1.08-1.30) and the test of heterogeneity resulted into Q = 57.44 ( I2 = 68.67%, P ≤ .001). The risk of offspring obesity is 1.23 (95% CI, 1.09-1.39) and the test of heterogeneity resulted into Q = 39.55 ( I2 = 69.66%, P ≤ .001). Children born by cesarean section have an increased risk of obesity in adulthood.

Acid Suppression and Antibiotics Administered during Infancy Are Associated with Celiac Disease

OBJECTIVE

To investigate why certain at-risk individuals develop celiac disease (CD), we examined the association of proton pump inhibitors (PPI), histamine-2 receptor antagonists (H2RAs), and antibiotic prescriptions in the first 6 months of life with an early childhood diagnosis of CD.

STUDY DESIGN

A retrospective cohort study was performed using the Military Healthcare System database. Children with a birth record from October 1, 2001, to September 30, 2013, were identified. Outpatient prescription records were queried for antibiotic, PPI, and H2RA prescriptions in the first 6 months of life. Cox proportional hazards regression was used to calculate the hazard ratio (HR) of developing CD based on medication exposure. International Classification of Diseases, Ninth Revision, Clinical Modification codes identified children with an outpatient visit for CD.

RESULTS

There were 968 524 children who met the inclusion criteria with 1704 cases of CD in this group. The median follow-up for the cohort was approximately 4.5 years. PPIs (HR, 2.23; 95% CI, 1.76-2.83), H2RAs (HR, 1.94; 95% CI, 1.67-2.26), and antibiotics (HR, 1.14; 95% CI, 1.02-1.28) were all associated with an increased hazard of CD.

CONCLUSIONS

There is an increased risk of developing CD if antibiotics, PPIs and H2RAs are prescribed in the first 6 months of life. Our study highlights modifiable factors, such as medication stewardship, that may change the childhood risk of CD.

Why are western diet and western lifestyle pro-inflammatory risk factors of celiac disease?

The prevalence of celiac disease increased in recent years. In addition to the genetic and immunological factors, it appears that environmental determinants are also involved in the pathophysiology of celiac disease. Gastrointestinal infections impact the development of celiac disease. Current research does not directly confirm the protective effect of natural childbirth and breastfeeding on celiac disease. However, it seems that in genetically predisposed children, the amount of gluten introduced into the diet may have an impact on celiac disease development. Also western lifestyle, including western dietary patterns high in fat, sugar, and gliadin, potentially may increase the risk of celiac disease due to changes in intestinal microbiota, intestinal permeability, or mucosal inflammation. Further research is needed to expand the knowledge of the relationship between environmental factors and the development of celiac disease to define evidence-based preventive interventions against the development of celiac disease. The manuscript summarizes current knowledge on factors predisposing to the development of celiac disease including factors associated with the western lifestyle.

Urbanisation and its Associated Factors Affecting Human Gut Microbiota: Where are we Heading to?

ContextThe continuous rise in urbanisation and its associated factors have been reflected in the structure of the human gut ecosystem.ObjectiveThe main focus of the review is to discuss and summarise the major risk factors associated with urbanisation that affects human gut microbiota thus affecting human health.MethodsMultiple medical literature databases, namely PubMed, Google, Google Scholar, and Web of Science were used to find relevant materials for urbanization and its major factors affecting human gut microbiota/microbiome. Both layman and Medical Subject Headings (MeSH) terms were used in the search. Due to the scarcity of the data, no limitation was set on the publication date. Relevant material in the English language which includes case reports, chapters of books, journal articles, online news reports and medical records was included in this review.ResultsBased on the data discussed in the review, it is quite clear that urbanisation and its associated factors have long-standing effects on the human gut microbiota that result in alterations of gut microbial diversity and composition. This is a matter of serious concern as chronic inflammatory diseases are on the rise in urbanised societies.ConclusionA better understanding of the factors associated with urbanisation will help us to identify and implement new biological and social approaches to prevent and treat diseases and improve health globally by deepening our understanding of these relationships and increasing studies across urbanisation gradients.HIGHLIGHTSHuman gut microbiota has been linked to almost every important function, including metabolism, intestinal homeostasis, immune system, biosynthesis of vitamins, brain processes, and its behaviour.However, dysbiosis i.e., alteration in the composition and diversity of gut microbiota is associated with the pathogenesis of many chronic conditions.In the 21st century, urbanisation represents a major demographic shift in developed and developing countries.During this period of urbanisation, humans have been exposed to many environmental exposures, all of which have led to the dysbiosis of human gut microbiota.The main focus of the review is to discuss and summarize the major risk factors associated with urbanisation and how it affects the diversity and composition of gut microbiota which ultimately affects human health.

Disquiet concerning cesarean birth

Cesarean birth has increased substantially in many parts of the world over recent decades and concerns have been raised about the propriety of this change in obstetric practice. Sometimes, a cesarean is necessary to preserve fetal and maternal health. But in balancing the risks of surgical intervention the implicit assumption has been that cesarean birth is an equivalent alternative to vaginal birth from the standpoint of the immediate and long-term health of the fetus and neonate. Increasingly, we realize this is not necessarily so. Delivery mode per se may influence short-term and abiding problems with homeostasis in offspring, quite independent of the indications for the delivery and other potentially confounding factors. The probability of developing various disorders, including respiratory compromise, obesity, immune dysfunction, and neurobehavioral disorders has been shown in some studies to be higher among individuals born by cesarean. Moreover, many of these adverse effects are not confined to the neonatal period and may develop over many years. Although the associations between delivery mode and long-term health are persuasive, their pathogenesis and causality remain uncertain. Full exploration and a clear understanding of these relationships is of great importance to the health of offspring.

Systems to model the personalized aspects of microbiome health and gut dysbiosis

The human gut microbiome is a complex and dynamic microbial entity that interacts with the environment and other parts of the body including the brain, heart, liver, and immune system. These multisystem interactions are highly conserved from invertebrates to humans, however the complexity and diversity of human microbiota compositions often yield a context that is unique to each individual. Yet commonalities remain across species, where a healthy gut microbiome will be rich in symbiotic commensal biota while an unhealthy gut microbiota will be experiencing abnormal blooms of pathobiont bacteria. In this review we discuss how omics technologies can be applied in a personalized approach to understand the microbial crosstalk and microbial-host interactions that affect the delicate balance between eubiosis and dysbiosis in an individual gut microbiome. We further highlight the strengths of model organisms in identifying and characterizing these conserved synergistic and/or pathogenic host-microbe interactions. And finally, we touch upon the growing area of personalized therapeutic interventions targeting gut microbiome.

Prematurity, Delivery Method, and Infant Feeding Type Are Not Associated with Paediatric-onset Inflammatory Bowel Disease Risk: A Scottish Retrospective Birth Cohort Study

BACKGROUND AND AIMS

The incidence of paediatric-onset inflammatory bowel disease [PIBD] continues to rise globally. We aimed to determine whether mode of delivery, gestational age at birth, or type of infant feeding contribute to the development of PIBD in a nationwide cohort of Scottish children.

METHODS

All children born in Scotland between 1981 and 2017 were identified using linked health administrative data to determine mode of delivery, gestational age at birth, and type of infant feeding. PIBD cases were defined as onset of Crohn's disease [CD], ulcerative colitis [UC], or IBD-unclassified [IBDU] before age 16 years. Validation was performed within an entire Scottish health board [16% of total population] via individual case-note verification. Hazard ratios [HR] were calculated for each exposure using Cox proportional hazards models.

RESULTS

A study population of 2 013 851 children was identified including 1721 PIBD cases. Validation of 261 PIBD patients coded as CD and/or UC identified 242 [93%] as true positive. Children delivered vaginally did not have an altered risk of developing PIBD compared with those delivered by caesarean section, adjusted HR 0.95 [95% CI 0.84-1.08] [p = 0.46]. Compared with children born at term [≥37 weeks], children born prematurely did not have an altered risk of developing PIBD, i.e., at 24-31 weeks of gestation, HR 0.99 [95% CI 0.57-1.71] [p = 0.97] and at 32-36 weeks of gestation, HR 0.96 [95% CI 0.76-1.20] [p = 0.71]. Compared with children exclusively breastfed at age 6 weeks, children exclusively formula fed did not have an altered risk of developing PIBD: adjusted HR 0.97 [95% CI 0.81-1.15] [p = 0.69].

CONCLUSIONS

This population-based study demonstrates no association between mode of delivery, gestational age, or exclusive formula feeding at 6 weeks, and the development of PIBD.

Delivery mode and risk of gastrointestinal disease in the offspring

INTRODUCTION

The global increase of individuals born by cesarean section with reported levels up to 20% of all deliveries, makes it important to study cesarean section and possible associations that can increase risk of subsequent diseases in children. The aim of the study was to evaluate if cesarean section is associated with increased risk of gastrointestinal disease later in life in a large population-based cohort.

MATERIAL AND METHODS

In this national population-based cohort study including all full-term individuals registered in the Medical Birth Register in Sweden between 1990 and 2000, type of delivery (exposure) was collected from the Medical Birth Register. The study population was followed until 2017 with regards to the outcomes: inflammatory bowel disease (Crohn's disease or ulcerative colitis), appendicitis, cholecystitis, or diverticulitis registered in the Swedish National Patient Register. Cox proportional-hazards models compared disease-free survival time between exposed and unexposed.

RESULTS

The final study population consisted of 1 102 468 individuals of whom 11.6% were delivered by cesarean section and 88.4% were vaginally delivered. In univariate analysis, cesarean section was associated with Crohn's disease (hazard ratio [HR] 1.13, 95% confidence interval [CI] 1.02-1.25), diverticulosis (HR 1.57, 95% CI 1.13-2.18), and cholecystitis (HR 1.16, 95% CI 1.05-1.28). However, the increased risk only remained for Crohn's disease after adjustment for confounders (HR 1.14, 95% CI 1.02-1.27). No associations between delivery mode and appendicitis, ulcerative colitis, cholecystitis, or diverticulosis were found in the multivariate analysis.

CONCLUSIONS

Cesarean section is associated with Crohn's disease later in life, but no other association between delivery mode and gastrointestinal disorders later in life could be found.

Cesarean section is not associated with increased risk of celiac disease in the offspring: a meta-analysis

OBJECTIVE

Epidemiologic findings are inconsistent concerning the association between cesarean section (C-section) and celiac disease in offspring.

METHODS

We performed a systematic literature search of PubMed and Embase databases until July 2021. A meta-analysis was performed for each outcome in which a summary odds ratio (OR) was calculated while taking heterogeneity into account.

RESULTS

A total of 11 observational were identified for the literature review. We found that C-section was not associated with an increase in the risk of CD (OR = 1.03, 95% CI, 0.95-1.12; p = .501). In subgroup analyses, the association remained insignificant for both infants born after elective C-section (OR 1.05; 0.95-1.16; p = .329) and emergency C-section (OR 1.06; 1-1.13; p = .051).

CONCLUSIONS

Our results indicate that C-section is not associated with CD in offspring.

Animal Models for Assessing Impact of C-Section Delivery on Biological Systems

There has been a significant increase in Caesarean section (C-section) births worldwide over the past two decades and although it is can be a life-saving procedure, the enduring effects on host physiology are now undergoing further scrutiny. Indeed, epidemiological data have linked C-section birth with multiple immune, metabolic and neuropsychiatric diseases. Birth by C-section is known to alter the colonisation of the neonatal gut microbiota (with C-section delivered infants lacking vaginal microbiota associated with passing along the birth canal), which in turn can impact the development and maintenance of many important biological systems. Appropriate animal models are key to disentangling the role of missing microbes in brain health and disease in C-section births. In this review of preclinical studies, we interrogate the effects of C-section birth on the development (and maintenance) of several biological systems and we discuss the involvement of the gut microbiome on C-section-related alterations.

Maternal and early life exposures and their potential to influence development of the microbiome

At the dawn of the twentieth century, the medical care of mothers and children was largely relegated to family members and informally trained birth attendants. As the industrial era progressed, early and key public health observations among women and children linked the persistence of adverse health outcomes to poverty and poor nutrition. In the time hence, numerous studies connecting genetics ("nature") to public health and epidemiologic data on the role of the environment ("nurture") have yielded insights into the importance of early life exposures in relation to the occurrence of common diseases, such as diabetes, allergic and atopic disease, cardiovascular disease, and obesity. As a result of these parallel efforts in science, medicine, and public health, the developing brain, immune system, and metabolic physiology are now recognized as being particularly vulnerable to poor nutrition and stressful environments from the start of pregnancy to 3 years of age. In particular, compelling evidence arising from a diverse array of studies across mammalian lineages suggest that modifications to our metagenome and/or microbiome occur following certain environmental exposures during pregnancy and lactation, which in turn render risk of childhood and adult diseases. In this review, we will consider the evidence suggesting that development of the offspring microbiome may be vulnerable to maternal exposures, including an analysis of the data regarding the presence or absence of a low-biomass intrauterine microbiome.

Peripartum Antibiotics Exposure and the Risk of Autoimmune and Autism Disorders in the Offspring

Background As the use of antibiotics during the peripartum period increases, the incidence of autoimmune disorders and autism spectrum disorders (ASDs) is also increasing. In this study, we aim to assess if antibiotic exposure during the peripartum period affects the incidence of autoimmune diseases and ASD in the offspring. Methods We identified children (< 18 years of age) born in Olmsted County from January 1, 2003 through December 31, 2012. Offspring with celiac disease (CD), inflammatory bowel disease (IBD), or ASD diagnoses were matched to two controls on birth date, index date, mother's age at delivery, and sex. Data from the mother's medical records were retrieved to determine peripartum antibiotics use. Results A total of 242 cases and 484 matched controls were included in this study. Median age at the last follow-up was 11.3 years (range: 0.5-14.9), 73% were males in both groups. Odds of CD diagnosis was not statistically different between vaginal delivery with antibiotics compared with vaginal delivery with no antibiotics (odds ratio [OR] = 0.76, 95% confidence interval [CI]: 0.32-1.85), similarly in IBD (OR = 2.41, 95% CI: 0.53-10.98) and ASD (OR = 1.00, 95% CI:0.55-1.79). Preeclampsia or eclampsia was associated with offspring CD (OR = 3.20, 95% CI: 1.05-9.78). Smoking history and diabetes mellitus were associated with offspring ASD (OR = 1.84, 95% CI: 1.22-2.77 and OR = 2.01, 95% CI: 1.03-3.91, respectively). Conclusion In this cohort, we found no statistically significant association between peripartum antibiotics exposure and the development of CD, IBD, or ASD.

Association of cesarean birth with prevalence of functional constipation in toddlers at 3 years of age: results from the Japan Environment and Children's Study (JECS)

BACKGROUND

The association between delivery mode and subsequent development of diseases is a growing area of research. Cesarean delivery affects the diversity of the microbiota in the infant gut, which may be associated with gastrointestinal disorders, including functional constipation, in infants. In this study, we investigated the association between delivery mode and prevalence of functional constipation in 3-year-old Japanese toddlers.

METHODS

This study used data from the Japan Environment and Children's Study, an ongoing nationwide birth cohort study. We analyzed 71,878 toddler-mother pairs. The presence of functional constipation was determined according to the Rome III diagnostic criteria. Odds ratios and 95% confidence intervals were calculated using logistic regression analysis.

RESULTS

The prevalence of functional constipation in 3-year-old Japanese toddlers was estimated to be 12.3%. Logistic regression analysis revealed that the prevalence of functional constipation was higher in toddlers born by cesarean delivery (13.1%) compared with those born by vaginal delivery (12.1%), independent of 22 confounders (adjusted odds ratios = 1.064, 95% confidence interval = 1.004-1.128).

CONCLUSIONS

We determined the prevalence of functional constipation in 3-year-old Japanese toddlers and found that delivery mode was associated with the prevalence of functional constipation in Japanese toddlers.

Early life exposures and the risk of inflammatory bowel disease: Systematic review and meta-analyses

BACKGROUND

Early life exposures impact immune system development and therefore the risk of immune-mediated diseases, including inflammatory bowel disease (IBD). We systematically reviewed the impact of pre-, peri‑, and postnatal exposures up to the age of five years on subsequent IBD diagnosis.

METHODS

We identified case-control and cohort studies reporting on the association between early life environmental factors and Crohn's disease (CD), ulcerative colitis (UC), or IBD overall. Databases were search from their inception until May 24th, 2019 until July 14th, 2020. We conducted meta-analyses for quantitative review of relevant risk factors that were comparable across studies and qualitative synthesis of the literature for a wide range of early life exposures, including maternal health and exposures during pregnancy, perinatal factors, birth month and related-factors, breastfeeding, hygiene-related factors and social factors, immigration, antibiotics, offspring health, including infections, and passive smoking. PROSPERO registration: CRD42019134980.

FINDINGS

Prenatal exposure to antibiotics (OR 1.8; 95% CI 1.2-2.5) and tobacco smoke (OR 1.5; 95% CI 1.2-1.9), and early life otitis media (OR 2.1; 95% CI 1.2-3.6) were associated with IBD. There was a trend towards an association between exposure to antibiotics in infancy and IBD (OR: 1.7, 95% CI 0.97, 2.9), supported by positive data on population-based data. Breastfeeding was protective against IBD. Other early life risk factors had no association with IBD, but data were limited and heterogenous.

INTERPRETATION

Early life is an important period of susceptibility for IBD development later in life. Tobacco smoke, infections and antibiotics were associated positively, and breastfeeding was associated negatively with IBD. Our findings offer an opportunity to develop primary prevention strategies.

FUNDING

This study did not receive any funding.

Caesarean delivery and early childhood caries: Estimation with marginal structural models in Brazilian pre-schoolers

OBJECTIVE

This study analysed the association between caesarean section and early childhood caries (ECC), estimating the effects using regression and causal inference models.

METHODS

This was a historical cohort study of 697 mother-child dyads, conducted in São Luís, Brazil. The caesarean section was the exposure, and the severity of ECC (dmft) was the outcome. Covariates household income, maternal schooling, maternal hypertension, maternal obesity and birth weight were adjusted for in the models. The effects were estimated by Poisson regression (Means Ratio-MR) and causal inference using a marginal structural model (MSM) (MR and Average Treatment Effect-ATE coefficients), weighted by the inverse probability (IPW) of exposure.

RESULTS

Caesarean section was protective against caries in the bivariate (MR 0.81; CI 0.70-0.94; P = 0.005) and multivariate (MR 0.78; CI 0.67-0.91; P = 0.002) models. In MSM analyses, the caesarean section had no effect on ECC (ATE = -0.35; P = 0.107), controlling for IPW of exposure.

CONCLUSION

The apparent association between caesarean section and ECC severity seems spurious, as it did not persist after employing a superior approach to estimating causality.

Human Milk Microbiota and Oligosaccharides: A Glimpse into Benefits, Diversity, and Correlations

Human milk represents a cornerstone for growth and development of infants, with extensive array of benefits. In addition to exceptionally nutritive and bioactive components, human milk encompasses a complex community of signature bacteria that helps establish infant gut microbiota, contributes to maturation of infant immune system, and competitively interferes with pathogens. Among bioactive constituents of milk, human milk oligosaccharides (HMOs) are particularly significant. These are non-digestible carbohydrates forming the third largest solid component in human milk. Valuable effects of HMOs include shaping intestinal microbiota, imparting antimicrobial effects, developing intestinal barrier, and modulating immune response. Moreover, recent investigations suggest correlations between HMOs and milk microbiota, with complex links possibly existing with environmental factors, genetics, geographical location, and other factors. In this review, and from a physiological and health implications perspective, milk benefits for newborns and mothers are highlighted. From a microbiological perspective, a focused insight into milk microbiota, including origins, diversity, benefits, and effect of maternal diet is presented. From a metabolic perspective, biochemical, physiological, and genetic significance of HMOs, and their probable relations to milk microbiota, are addressed. Ongoing research into mechanistic processes through which the rich biological assets of milk promote development, shaping of microbiota, and immunity is tackled.

Mode of Delivery Does Not Affect the Risk of Inflammatory Bowel Disease

BACKGROUND

Recent evidence suggests that exposures in early life that are known to influence microbiome development may affect the risk of developing inflammatory bowel disease (IBD). Cesarean section has been associated with altered colonization of commensal gut flora and is thought to predispose to immune-mediated diseases later in life.

AIMS

To evaluate the risk of IBD, Crohn's Disease (CD), and Ulcerative Colitis (UC) according to mode of delivery (C-section vs vaginal delivery).

METHODS

A systematic search was performed in PubMed and Embase. The primary outcome was the risk of IBD in individuals delivered vaginally compared to those born by C-section. Secondary outcomes were UC and CD risk according to mode of delivery and IBD risk in individuals born by emergent compared to elective C-section. Publication bias was evaluated by funnel plots and Egger's test. Study's quality was characterized using the Newcastle-Ottawa Scale.

RESULTS

Ten studies fulfilled the inclusion criteria, of which seven were population-based. No publication bias was detected. Overall, 14.164 IBD patients and 4.206.763 controls were included. Being born by C-section was not associated with increased risk of IBD [OR 1.01, 95% CI (0.81-1.27), p = 0.92], CD [OR 1.15, 95% CI (0.94-1.42), p = 0.18] or UC [OR 0.94, 95% CI (0.61-1.45), p = 0.79]. No differences were found between emergent and elective C-section in IBD [OR 1.05, 95% CI (0.59-1,87), p = 0.87]. Substantial heterogeneity was found in statistical analysis, and further studies are needed.

CONCLUSION

Overall, the risk of developing IBD was not affected by mode of delivery.

The views of pregnant women in New Zealand on vaginal seeding: a mixed-methods study

Background

Vaginal seeding is the administration of maternal vaginal bacteria to babies following birth by caesarean section (CS), intended to mimic the microbial exposure that occurs during vaginal birth. Appropriate development of the infant gut microbiome assists early immune development and might help reduce the risk of certain health conditions later in life, such as obesity and asthma. We aimed to explore the views of pregnant women on this practice.

Methods

We conducted a sequential mixed-methods study on the views of pregnant women in New Zealand (NZ) on vaginal seeding. Phase one: brief semi-structured interviews with pregnant women participating in a clinical trial of vaginal seeding (n = 15); and phase two: online questionnaire of pregnant women throughout NZ (not in the trial) (n = 264). Reflexive thematic analysis was applied to interview and open-ended questionnaire data. Closed-ended questionnaire responses were analysed using descriptive statistics.

Results

Six themes were produced through analysis of the open-ended data: “seeding replicates a natural process”, “microbiome is in the media”, “seeding may have potential benefits”, “seeking validation by a maternity caregiver”, “seeding could help reduce CS guilt”, and “the unknowns of seeding”. The idea that vaginal seeding replicates a natural process was suggested by some as an explanation to help overcome any initial negative perceptions of it. Many considered vaginal seeding to have potential benefit for the gut microbiome, while comparatively fewer considered it to be potentially beneficial for specific conditions such as obesity. Just under 30% of questionnaire respondents (n = 78; 29.5%) had prior knowledge of vaginal seeding, while most (n = 133; 82.6%) had an initially positive or neutral reaction to it. Few respondents changed their initial views on the practice after reading provided evidence-based information (n = 60; 22.7%), but of those who did, most became more positive (n = 51; 86.4%).

Conclusions

Given its apparent acceptability, and if shown to be safe and effective for the prevention of early childhood obesity, vaginal seeding could be a non-stigmatising approach to prevention of this condition among children born by CS. Our findings also highlight the importance of lead maternity carers in NZ remaining current in their knowledge of vaginal seeding research.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-020-03500-y.

Gut microbiota in Celiac Disease: microbes, metabolites, pathways and therapeutics

INTRODUCTION

Current evidence supports a vital role of the microbiota on health outcomes, with alterations in an otherwise healthy balance linked to chronic medical conditions like celiac disease (CD). Recent advances in microbiome analysis allow for unparalleled profiling of the microbes and metabolites. With the growing volume of data available, trends are emerging that support a role for the gut microbiota in CD pathogenesis.

AREAS COVERED

In this article, the authors review the relationship between factors such as genes and antibiotic exposure on CD onset and the intestinal microbiota. The authors also review other microbiota within the human body (like the oropharynx) that may play a role in CD pathogenesis. Finally, the authors discuss implications for disease modification and the ultimate goal of prevention. The authors reviewed literature from PubMed, EMBASE, and Web of Science.

EXPERT OPINION

CD serves as a unique opportunity to explore the role of the intestinal microbiota on the development of chronic autoimmune disease. While research to date provides a solid foundation, most studies have been case-control and thus do not have capacity to explore the mechanistic role of the microbiota in CD onset. Further longitudinal studies and integrated multi-omics are necessary for investigating CD pathogenesis.

Neonatal thermal response to childbirth: Vaginal delivery vs. caesarean section

Newborns, regardless of the method of termination of pregnancy, are exposed to the first exogenous stress factors during delivery. The purpose of the study was to evaluate the differences in newborns' thermal response to vaginal (VD) vs caesarean section (CS) delivery. The temperature was measured during the first minutes of life within 122 healthy full-term newborns, on the forehead, chest and upper-back by infrared camera (FLIR T1030sc HD). The lowest temperatures were recorded in the forehead of VD newborns (significantly difference with CS; p < 0.001), the warmest was the chest. A significant correlation was found between the duration of the second stage of natural childbirth and surface temperature and pO2 in the newborn blood. The temperatures of selected body surface areas correlate highly positively, regardless of the mode of delivery. In the case of healthy neonates, with normal birth weight and full-term, VD creates more favourable conditions stimulating the mechanisms of adaptation for a newborn than CS.

Role of the gut microbiota in the pathogenesis of coeliac disease and potential therapeutic implications

PURPOSE

Although genetic predisposition and exposure to dietary gluten are considered necessary triggers for the development of coeliac disease, alterations in the gut microbial composition may also contribute towards the pathogenesis of coeliac disease. This review aims to provide an overview of the available data on the potential mechanisms through which the gut microbiota plays a role in the causation of coeliac disease and to discuss the potential therapeutic strategies that could diminish the consequences of microbial dysbiosis.

METHOD

A search of the literature was performed using the PubMed, Embase, and JSTOR databases; relevant articles were included.

RESULTS

Recent studies in patients with coeliac disease have reported an increase in the relative amounts of gram negative bacterial genera such as Bacteroides, Prevotella, and Escherichia, and reduced amounts of protective anti-inflammatory bacteria such as Bifidobacteria and Lactobacilli. Dysbiotic microbiota may lead to a dysregulated immune response that may contribute to the pathogenesis of coeliac disease. In infancy, antibiotic use and certain infant feeding practices may lead to alterations in the developing gut microbiota to influence the immune maturation process and predispose to coeliac disease.

CONCLUSION

The induction of the intestinal immune system and gluten intolerance may be influenced by the relative abundance of certain microbiota. Factors such as infant feeding practices, diet, antibiotics, and infections, may be involved in the development of coeliac disease due to their influence on gut microbial composition. The efficacy of potential modulators of the gut microbiota such as probiotics, prebiotics, and fecal microbial transplant as adjunctive treatments to gluten-free diet in coeliac disease is unproven and requires further investigation.

Sows affect their piglets' faecal microbiota until fattening but not their Salmonella enterica shedding status

Recent studies have shown that Salmonella shedding status affects sows' microbiota during gestation and that these modifications are reflected in the faecal microbiota of their piglets at weaning. The aims of this study were: (a) to evaluate the persistence, up to the fattening period, of the previously measured link between the microbiota of piglets and their mothers' Salmonella shedding status; and (b) measure the impact of the measured microbiota variations on their Salmonella excretion at this stage. To achieve this, 76 piglets born from 19 sows for which the faecal microbiota was previously documented, were selected in a multisite production system. The faecal matter of these swine was sampled after 4 weeks, at the fattening stage. The Salmonella shedding status and faecal microbiota of these animals were described using bacteriological and 16S rRNA gene amplicon sequencing respectively. The piglet digestive microbiota association with the Salmonella shedding status of their sows did not persist after weaning and did not affect the risk of Salmonella excretion during fattening, while the birth mother still affected the microbiota of the swine at fattening. This supports the interest in sows as a target for potentially transferrable microbiota modifications.

The Role of Early Programming and Early Nutrition on the Development and Progression of Celiac Disease: A Review

Experimental and epidemiological evidence has shown that modifications of the intrauterine environment can have deleterious consequences for individuals, expressed as an increased risk of suffering non-communicable pathologies in adult life, which is known as the hypothesis of the early origin of diseases or fetal programming. On the other hand, changes in gene expression patterns through epigenetic modifications can be the basis for long-term maintenance of the effects of fetal programming. In this sense, epigenetics comprises the study of intrauterine disturbances, which develop diseases in the adult, including celiac disease (CD). In addition, early feeding practices could influence the risk of CD development, such as breastfeeding timing and duration and age of gluten introduction in the diet. Gluten acts as a trigger for CD in genetically predisposed subjects, although approximately 30% of the world population has HLA DQ2 or DQ8, the prevalence of the disease is only 1–3%. It is not known what factors act to modify the risk of disease in genetically at-risk subjects. Taking into account all these considerations, the aim of the current review is to elucidate the role of early programming and the effect of early nutrition on the development and progression of CD. It is logical that attention has been paid to gluten as a key element in preventing the disease. However, there is no strong evidence in favor of the protective factor of breastfeeding, timing of introduction of gluten during lactation, and the development of CD. Diet, genetic risk, microbiota, and environmental interaction are possible triggers of the change in tolerance to an immune response to gluten, but large-scale cohort studies are needed. Emerging scientific concepts, such as epigenetics, may help us establish the role of these factors.

Pediatrics Consequences of Caesarean Section-A Systematic Review and Meta-Analysis

BACKGROUND

Cesarean section is a surgical procedure, which is the most frequently performed in gynecology and obstetrics. It is commonly believed that an operative delivery is a less painful and safer mode of delivery, which translates into an increasing number of the procedures performed without medical indications. The maternal sequelae of cesarean sections are well elucidated and widely discussed in the literature, while long-term neonatal consequences still remain the issue of research and scientific dispute. The aim of the present paper was to perform a systematic review of current literature regarding pediatrics consequences of cesarean section.

METHODS

We reviewed available data from PubMed, Science Direct as well as Google Scholar bases concerning early and long-term neonatal sequelae of operative deliveries. The following key words were used: "cesarean section", "caesarean section", "neonatal outcomes", "respiratory disorders", "asthma", "obesity", "overweight", and "neurological disorders". A total of 1636 papers were retrieved out of which 27 were selected for the final systematic review whereas 16 articles provided data for meta-analysis. Statistical analyses were performed using RevMan 5.4. To determine the strength of association between the caesarean section and respiratory tract infections, asthma, diabetes type 1 as well as obesity the pooled odds ratios (OR) with the 95% confidence intervals (CI) were calculated.

RESULTS

Conducted meta-analyses revealed that caesarean section is a risk factor for respiratory tract infections (pooled OR = 1.30 95%CI 1.06-1.60, p = 0.001), asthma (pooled OR = 1.23 95%CI 1.14-1.33, p < 0.00001) as well as obesity (pooled OR = 1.35 95%CI 1.29-1.41, p < 0.00001) in offspring.

CONCLUSIONS

The results of the studies included indicated that children delivered by cesarean section more commonly developed respiratory tract infections, obesity and the manifestations of asthma than children delivered vaginally. The risk of developing diabetes mellitus type 1 or neurological disorders in offspring after caesarean section is still under discussion.

Multi-omics analysis reveals the influence of genetic and environmental risk factors on developing gut microbiota in infants at risk of celiac disease

BACKGROUND

Celiac disease (CD) is an autoimmune digestive disorder that occurs in genetically susceptible individuals in response to ingesting gluten, a protein found in wheat, rye, and barley. Research shows that genetic predisposition and exposure to gluten are necessary but not sufficient to trigger the development of CD. This suggests that exposure to other environmental stimuli early in life, e.g., cesarean section delivery and exposure to antibiotics or formula feeding, may also play a key role in CD pathogenesis through yet unknown mechanisms. Here, we use multi-omics analysis to investigate how genetic and early environmental risk factors alter the development of the gut microbiota in infants at risk of CD.

RESULTS

Toward this end, we selected 31 infants from a large-scale prospective birth cohort study of infants with a first-degree relative with CD. We then performed rigorous multivariate association, cross-sectional, and longitudinal analyses using metagenomic and metabolomic data collected at birth, 3 months and 6 months of age to explore the impact of genetic predisposition and environmental risk factors on the gut microbiota composition, function, and metabolome prior to the introduction of trigger (gluten). These analyses revealed several microbial species, functional pathways, and metabolites that are associated with each genetic and environmental risk factor or that are differentially abundant between environmentally exposed and non-exposed infants or between time points. Among our significant findings, we found that cesarean section delivery is associated with a decreased abundance of Bacteroides vulgatus and Bacteroides dorei and of folate biosynthesis pathway and with an increased abundance of hydroxyphenylacetic acid, alterations that are implicated in immune system dysfunction and inflammatory conditions. Additionally, longitudinal analysis revealed that, in infants not exposed to any environmental risk factor, the abundances of Bacteroides uniformis and of metabolite 3-3-hydroxyphenylproprionic acid increase over time, while those for lipoic acid and methane metabolism pathways decrease, patterns that are linked to beneficial immunomodulatory and anti-inflammatory effects.

CONCLUSIONS

Overall, our study provides unprecedented insights into major taxonomic and functional shifts in the developing gut microbiota of infants at risk of CD linking genetic and environmental risk factors to detrimental immunomodulatory and inflammatory effects. Video Abstract.

The Association Between Caesarean Section and Inflammatory Bowel Disease in Childhood and Young Adulthood: Findings From 2 Retrospective Cohort Studies

OBJECTIVE

The aim of the study was to examine the association of Caesarean section (CS) with inflammatory bowel disease (IBD) in Nova Scotian children.

METHODS

The study consisted of 2 retrospective cohorts in the Canadian province of Nova Scotia: all births between 1988 and 2014 (n = 262,729) linked with a clinical registry of all children diagnosed with IBD at the IWK Health Centre, Halifax (Clinical Cohort) and all births from 1989 to 1993 (n = 42,999) linked with provincial administrative health data (Administrative Cohort). The primary outcome was a diagnosis of IBD; the outcome in the Administrative Cohort was ascertained using a previously validated algorithm. Information on the exposures and confounding variables was obtained from the Nova Scotia Atlee Perinatal Database. The association between CS and time to diagnosis of IBD was examined using survival analysis.

RESULTS

The population incidence of IBD in the Clinical and Administrative Cohort were 13.0 and 20.6, respectively, per 100,000 person-years; 23% and 19% of children were born by CS in the 2 cohorts. There was no association of CS with IBD in the 2 cohorts.

CONCLUSIONS

Findings from 2 population-based cohorts in Atlantic Canada did not provide any evidence for an association between CS and IBD in childhood and young adulthood.

Maternal bacteria to correct abnormal gut microbiota in babies born by C-section

INTRODUCTION

There is evidence that caesarean section (CS) is associated with increased risk of childhood obesity, asthma, and coeliac disease. The gut microbiota of CS-born babies differs to those born vaginally, possibly due to reduced exposure to maternal vaginal bacteria during birth. Vaginal seeding is a currently unproven practice intended to reduce such differences, so that the gut microbiota of CS-born babies is similar to that of babies born vaginally. Our pilot study, which uses oral administration as a novel form of vaginal seeding, will assess the degree of maternal strain transfer and overall efficacy of the procedure for establishing normal gut microbiota development.

METHODS AND ANALYSIS

Protocol for a single-blinded, randomized, placebo-controlled pilot study of a previously untested method of vaginal seeding (oral administration) in 30 CS-born babies. A sample of maternal vaginal bacteria is obtained prior to CS, and mixed with 5 ml sterile water to obtain a supernatant. Healthy babies are randomized at 1:1 to receive active treatment (3 ml supernatant) or placebo (3 ml sterile water). A reference group of 15 non-randomized vaginal-born babies are also being recruited. Babies' stool samples will undergo whole metagenomic shotgun sequencing to identify potential differences in community structure between CS babies receiving active treatment compared to those receiving placebo at age 1 month (primary outcome). Secondary outcomes include differences in overall gut community between CS groups (24 hours, 3 months); similarity of CS-seeded and placebo gut profiles to vaginally-born babies (24 hours, 1 and 3 months); degree of maternal vaginal strain transfer in CS-born babies (24 hours, 1 and 3 months); anthropometry (1 and 3 months) and body composition (3 months).

ETHICS AND DISSEMINATION

Ethics approval by the Northern A Health and Disability Ethics Committee (18/NTA/49). Results will be published in peer-reviewed journals and presented at international conferences.

REGISTRATION

Australian New Zealand Clinical Trials Registry (ACTRN12618000339257).

Brain Opioid Activity and Oxidative Injury: Different Molecular Scenarios Connecting Celiac Disease and Autistic Spectrum Disorder

Celiac Disease (CD) is an immune-mediated disease triggered by the ingestion of wheat gliadin and related prolamins from other cereals, such as barley and rye. Immunity against these cereal-derived proteins is mediated by pro-inflammatory cytokines produced by both innate and adaptive system response in individuals unable to adequately digest them. Peptides generated in this condition are absorbed across the gut barrier, which in these patients is characterized by the deregulation of its permeability. Here, we discuss a possible correlation between CD and Autistic Spectrum Disorder (ASD) pathogenesis. ASD can be induced by an excessive and inappropriate brain opioid activity during the neonatal period. Cereal-derived peptides produced in celiac patients cross the blood–brain barrier and bind to endogenous opioid receptors interfering with neurotransmission and generating deleterious effects on brain maturation, learning and social relations. Moreover, an increase in oxidative stress and a decrease in the antioxidant capacity, as well as an extended mitochondrial impairment in the brain, could represent a possible connection between ASD and CD. Therefore, we critically discuss the proposed relationship between ASD and CD and the possible usefulness of a gluten-free diet in ASD patients.

A cross-sectional pilot study of birth mode and vaginal microbiota in reproductive-age women

Recent studies suggest that birth mode (Cesarean section [C-section] or vaginal delivery) is an important event in the initial colonization of the human microbiome and may be associated with long-term health outcomes. We sought to determine the association between a woman's birth mode and her vaginal microbiota in adulthood. We re-contacted 144 adult women from two U.S. studies and administered a brief survey. Vaginal microbiota was characterized on a single sample by amplicon sequencing of the V3-V4 hypervariable regions of the 16S rRNA gene and clustered into community state types (CSTs). We evaluated the association between birth mode and a CST with low relative abundance of Lactobacillus spp. ("molecular bacterial vaginosis" [Molecular-BV]) compared to Lactobacillus-dominated CSTs in logistic regression modeling which adjusted for body mass index, a confounder in this analysis. Twenty-seven women (19%) reported C-section. Overall, C-section showed a non-significant trend towards increased odds of Molecular-BV (aOR = 1.22, 95% CI: 0.45, 3.32), and Prevotella bivia was the strongest single taxa associated with C-section. However, because the two archived studies had different inclusion criteria (interaction p = 0.048), we stratified the analysis by study site. In the study with a larger sample size (n = 88), women born by C-section had 3-fold higher odds of Molecular-BV compared to vaginally-delivered women (aOR = 3.55, p = 0.06, 95% CI: 0.97-13.02). No association was found in the smaller study (n = 56, aOR = 0.19, p = 0.14, 95% CI: 0.02-1.71). This pilot cross-sectional study suggests a possible association between C-section and Molecular-BV in adulthood. However, the analysis is limited by small sample size and lack of comparability in participant age and other characteristics between the study sites. Future longitudinal studies could recruit larger samples of women, address the temporal dynamics of vaginal microbiota, and explore other confounders, including maternal factors, breastfeeding history, and socioeconomic status, which may affect the relationship between birth mode and vaginal microbiota.

Caesarean Delivery and Risk of Chronic Inflammatory Diseases (Inflammatory Bowel Disease, Rheumatoid Arthritis, Coeliac Disease, and Diabetes Mellitus): A Population Based Registry Study of 2,699,479 Births in Denmark During 1973-2016

Background

Chronic inflammatory diseases in childhood and early adult life share aetiological factors operating from birth and onwards. In this study, we use data from the national Danish health registers to evaluate the risk of developing four common, immune-mediated hospital-diagnosed childhood chronic inflammatory diseases.

Methods

A national population-based registry study. Data from the Danish Medical Birth Registry and the Danish National Patient Registry from January 1973 to March 2016 were linked at a personal level to evaluate any potential associations between caesarean section and development of Inflammatory bowel diseases, rheumatoid arthritis, coeliac disease and diabetes mellitus among the offspring. A model adjusted for parental age at birth, decade of birth, gender of child, and parents' chronic inflammatory disease status was used.

Results

This register-based national cohort study of 2672708 children with information on delivery mode found an increased risk of diabetes, arthritis, coeliac disease, and inflammatory bowel disease for both girls and boys after caesarean section compared with vaginal delivery. The higher risk was present at least 40 years after delivery. In a subgroup analysis, both acute and elective caesarean section was associated with an increased risk of developing a chronic inflammatory disease.

Conclusions

Being born by caesarean section leads to increased host susceptibility for chronic inflammatory diseases that last for decades. This finding should be further addressed in future studies with the aim to support the development of new strategies for prevention, treatment, and maybe even cure.

Postnatal pediatric systemic antibiotic episodes during the first three years of life are not associated with mode of delivery

BACKGROUND

Delivery by cesarean section (C-section) is associated with adverse short-term and long-term infant outcomes. Given that antibiotics during early life are prescribed for infant outcomes that are more likely among c-section deliveries, we hypothesized that postnatal antibiotic exposure will be greater among c-section infants compared to vaginally delivered infants.

OBJECTIVE

The aim of this paper was to evaluate if mode of infant delivery was associated with patterns of systemic antibiotic exposure in children during their first three years.

METHODS

Pediatric electronic health records from UFHealth, 2011 to 2017 were reviewed. We included singleton, term infants (37-42 weeks gestation) with a birth weight ≥ 2500 grams, with documented mode of delivery and well visits on record. Infants with a neonatal intensive care unit stay were excluded. Both oral and intravenous antibiotics for a 10-day duration were classified as a single episode. The primary outcome was antibiotic episodes in the first three years of life, and a sub-analysis was performed to compare broad-spectrum versus narrow-spectrum antibiotic exposures.

RESULTS

The mean number of antibiotic episodes in 4,024 full-term infants was 0.34 (SD = 0.79) and 24.1% of infants had at least one antibiotic episode. Penicillins were the most prescribed antibiotic in children 0-1 years (66.9%) and cephalosporins were the most common antibiotic prescribed for children 1-3 years (56.2%). We did not detect a meaningful or significant rate ratio (RR) between mode of delivery and overall antibiotic episodes 1.14 (95% CI 0.99, 1.31), broad-spectrum episodes 1.19 (95% CI 0.93, 1.52, or narrow-spectrum episodes 1.14 (95% CI 0.97, 1.34).

CONCLUSION

Our results do not support the hypothesis that postnatal antibiotic exposure was greater among infants delivered by cesarean section compare to infants delivered vaginally during the first three years of life.

Epigenetic programming-The important first 1000 days

The perinatal period is a time of fast physiological change, including epigenetic programming. Adverse events may lead to epigenetic changes, with implications for health and disease. Our review covers the basics of clinical epigenetics and explores the latest research, including the role of epigenetic processes in complex disease phenotypes, such as neurodevelopmental, neurodegenerative and immunological disorders. Some studies suggest that epigenetic alterations are linked to early life environmental stressors, including mode of delivery, famine, psychosocial stress, severe institutional deprivation and childhood abuse. CONCLUSION: Epigenetic modifications due to perinatal environmental exposures can lead to lifelong, but potentially reversible, phenotypic alterations and disease.

The connection between microbiome and schizophrenia

There has been an accumulation of knowledge about the human microbiome, some detailed investigations of the gastrointestinal microbiota and its functions, and the highlighting of complex interactions between the gut, the gut microbiota, and the central nervous system. That assumes the involvement of the microbiome in the pathogenesis of various CNS diseases, including schizophrenia. Given this information and the fact, that the gut microbiota is sensitive to internal and environmental influences, we have speculated that among the factors that influence the formation and composition of gut microbiota during life, possible key elements in the schizophrenia development chain are hidden where gut microbiota is a linking component. This article aims to describe and understand the developmental relationships between intestinal microbiota and the risk of developing schizophrenia.

Celiac Disease and the Microbiome

Growing evidence supports the hypothesis that changes in both the composition and function of the intestinal microbiome are associated with a number of chronic inflammatory diseases including celiac disease (CD). One of the major advances in the field of microbiome studies over the last few decades has been the development of culture-independent approaches to identify and quantify the components of the human microbiota. The study of nucleic acids DNA and RNA found in feces or other biological samples bypasses the need for tissue cultures and also allows the characterization of non-cultivable microbes. Current evidence on the composition of the intestinal microbiome and its role as a causative trigger for CD is highly heterogeneous and sometimes contradictory. This review is aimed at summarizing both pre-clinical (basic science data) and clinical (cross-sectional and prospective studies) evidence addressing the relationship between the intestinal microbiome and CD.

The microbiota of the mother at birth and its influence on the emerging infant oral microbiota from birth to 1 year of age: a cohort study

Background: The acquisition of microbial communities and the influence of delivery mode on the oral microbiota of the newborn infant remains poorly characterised. Methods: A cohort of pregnant women were enrolled in the study (n = 84). All infants were born full term, by Spontaneous vaginal delivery (SVD) or by Caesarean section (CS). At delivery a saliva sample along with a vaginal/skin sample from the mother. Saliva samples were the taken from the infant within one week of birth, and at week 4, week 8, 6 months and 1 year of age. We used high-throughput sequencing of V4-V5 region 16S rRNA amplicons to compare the microbiota of all samples. Results: The vaginal microbiota had a lower alpha diversity than the skin microbiota of the mother, while the infant oral microbiota diversity remained relatively stable from birth to 8 weeks of age. The oral microbiota of the neonate differed by birth modality up to 1 week of age (p < 0.05), but birth modality did not have any influence on the infant oral microbiota beyond this age. Conclusions: We conclude thatbirth mode does not have an effect on the infant oral microbiota beyond 4 weeks of age, and the oral microbiota of infants continues to develop until 1 year of age.

Epidemiology of Celiac Disease

Celiac disease is a common, chronic inflammatory disorder of the small intestine triggered by exposure to gluten in individuals with certain genetic types. This disorder affects people of any age or gender. Although often thought to be European in origin, it is now global in extent. Presentations are variable, from asymptomatic patients to severe malnutrition. Initial detection usually relies on celiac-specific serology, and confirmation often requires intestinal biopsy. There have been substantial increases in prevalence and incidence over the last 2 decades for reasons that are almost certainly environmental but for which there is no clarity as to cause.

Infant milk-feeding practices and diagnosed celiac disease and inflammatory bowel disease in offspring: a systematic review

BACKGROUND

During the Pregnancy and Birth to 24 Months Project, the USDA and US Department of Health and Human Services initiated an evidence review on diet and health in these populations.

OBJECTIVE

The aim of these systematic reviews was to examine the relationships of never versus ever feeding human milk, shorter versus longer durations of any and exclusive human milk feeding, and feeding a lower versus a higher intensity of human milk to mixed-fed infants with diagnosed celiac disease and inflammatory bowel disease (IBD).

METHODS

The Nutrition Evidence Systematic Review team (formerly called the Nutrition Evidence Library) conducted systematic reviews with external experts. We searched CINAHL, Cochrane, Embase, and PubMed for articles published January, 1980 to March, 2016, dual-screened the results using predetermined criteria, extracted data from and assessed risk of bias for each included study, qualitatively synthesized the evidence, developed conclusion statements, and graded the strength of the evidence.

RESULTS

We included 9 celiac disease and 17 IBD articles. Limited case-control evidence suggests never versus ever being fed human milk is associated with higher risk of celiac disease, but concerns about reverse causality precluded a conclusion about the relationship of shorter versus longer durations of any human milk feeding with celiac disease. Evidence examining never versus ever feeding human milk and IBD was inconclusive, and limited, but consistent, case-control evidence suggests that, among infants fed human milk, shorter versus longer durations of any human milk feeding are associated with higher risk of IBD. For both outcomes, evidence examining the duration of exclusive human milk feeding was scant and no articles examined the intensity of human milk fed to mixed-fed infants.

CONCLUSION

Limited case-control evidence suggests that feeding human milk for short durations or not at all associates with higher risk of diagnosed IBD and celiac disease, respectively. The small number of studies and concern about reverse causality and recall bias prevent stronger conclusions.

The Microbiome in Celiac Disease

The healthy microbiome is necessary for normal immune development in the gut. Alterations in the microbial makeup after a critical window increase the risk of autoimmunity, including celiac disease. Although this dysbiosis has been described in adult and pediatric patients, factors leading to dysbiosis are still being elucidated. Genetics has some role in determining the microbiome makeup of the host, but other factors have yet to be determined. The microbiome remains an important therapeutic target in many autoimmune conditions, including celiac disease, however studies have yet to determine the ideal replacement therapy to correct the dysbiosis.

Caesarean birth and adiposity parameters in 6- to 8-year-old urban Maya children from two cities of Yucatan, Mexico

OBJECTIVES

The purpose of this study was to analyze the association between birth mode and fat mass index (FMI = fat mass [kg]/height [m]² ), and z-score values of waist circumference (WCZ) and sum of triceps and subscapular skinfolds (SumSkfZ) in a sample of 256 6- to 8-year-old urban Maya children from the cities of Merida and Motul in Yucatan, Mexico.

METHODS

From September 2011 to January 2014, we measured height, weight, waist circumference and skinfolds in children, and height and weight in their mothers. Body composition was estimated in both generations through bioelectrical impedance analysis. Data on children's birth mode and birth weight were obtained from birth certificates. A pre-validated questionnaire for mothers was used regarding household living conditions. Multiple regression models were used to analyze the association between birth mode and adiposity parameters, adjusting for the effect of place of residence, household crowding index, children's birth weight, and maternal fat mass. Separate regression models were run for boys and girls.

RESULTS

Caesarean-born children comprised 43% of the entire sample. Caesarean section (CS) was found to be associated with higher values of body adiposity in girls, but not in boys. Specifically, our models predicted that girls born by CS had an increased value of 0.817 kg/m² in FMI and showed higher SDs values for WCZ and SumskfZ (0.29 and 0.32 SD, respectively) than girls who were delivered vaginally.

DISCUSSION

Our results support the hypothesis that CS is associated with increased levels of adiposity in childhood, but only in girls.

Coeliac disease: beyond genetic susceptibility and gluten. A narrative review

Coeliac disease (CD) is an immune-mediated disorder triggered by the ingestion of gluten in genetically susceptible individuals. However, only a small proportion of subjects harbouring CD-related genetic risk develop the disease. Among the environmental factors that may influence CD risk, pre- and perinatal factors, delivery methods, parental lifestyle, infant feeding practices, seasonality, dietary factors, drug use, childhood infections and variability in gut microbiota are those most widely studied regarding the risk to develop CD. Although for many of these external factors the exact mechanism of action is unknown, most of them are thought to act by disrupting the intestinal barrier, facilitating contact between potential antigens and the immune system effector cells. Management of CD is relatively easy in patients with a definite diagnosis and requires a strict, lifelong, gluten-free diet. Better knowledge of environmental exposures apart from gluten can facilitate understanding of the pathogenesis of the disorder and the wide heterogeneity of its clinical spectrum. The purpose of this review is to discuss current knowledge on environmental CD risk factors, as well as possible interaction between them, on the grounds of the reliable scientific evidence available. Key messages The risk of developing CD is influenced not only by gluten ingestion but also by a number of environmental factors including childhood infections and variability in gut microbiota, pre- and perinatal factors, infant feeding practices, delivery methods, parental lifestyle, seasonality, dietary factors and drug use, acting mainly by disrupting intestinal permeability. Better knowledge of exposure to these factors can facilitate their identification, and subsequent elimination, in the individual patient.