A dietary intervention to improve the microbiome composition of pregnant women with Crohn's disease and their offspring: The MELODY (Modulating Early Life Microbiome through Dietary Intervention in Pregnancy) trial design

Prevention and interception trials in inflammatory bowel disease: an international taskforce assessment on clinical trial design

Therapeutic progress in inflammatory bowel disease (IBD) has hitherto focused on reducing inflammation to minimise long-term complications. However, strategies aimed at preventing IBD and attenuating its disease course are particularly appealing. This concept is derived from accumulating evidence for an "at-risk" preclinical state and the associations linking genetic background and numerous environmental exposures to disease pathogenesis. Trials in rheumatoid arthritis and type 1 diabetes have identified interventions to delay disease onset, modify the subsequent disease course (potentially protecting against irreversible tissue and end organ damage), and prolong normal quality of life. Prevention and interception trials have major challenges compared with therapeutic trials across a number of domains, including ethical considerations, eligibility criteria, sample size, and optimal endpoints. This Review investigates important factors in designing high-quality prevention trials and evaluates the feasibility and current progress of such trials in IBD, aiming to identify therapeutic strategies for populations at risk.

Early life factors, diet and microbiome, and risk of inflammatory bowel disease

Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), result from a loss of immune tolerance to gut microbiota, leading to inflammation. Their incidence is increasing, especially in newly industrialized countries. The etiology is multifactorial, involving genetic, immune, microbiota, and environmental factors. Maternal microbiome changes during pregnancy can elevate IBD risk in offspring, influenced by diet, smoking, and antibiotic exposure. Early life microbiota manipulation shows promise for preventing IBD. Epidemiological and pre-clinical studies highlight diet's significant role in IBD development. High-inflammatory dietary patterns correlate with increased CD risk, while Mediterranean-like diets promote beneficial gut microbiome changes and reduce inflammation. Certain food additives, such as emulsifiers and artificial sweeteners, may exacerbate IBD by altering gut microbiota. A systematic review indicates that higher ultra-processed food consumption significantly increases CD risk. Lifestyle modifications, including healthy dietary adherence, could substantially reduce IBD risk, with studies showing that favorable choices can halve the risk in genetically predisposed individuals. Additionally, maternal diet impacts offspring IBD risk, as seen in mouse models where high-fat diets led to increased inflammation. Evidence suggests that maternal probiotics and specific dietary patterns may mitigate these risks. Overall, these findings emphasize the potential for dietary interventions to modulate gut microbiota and immune responses, offering promising avenues for IBD prevention and management. Further large-scale studies are needed to explore the impact of dietary strategies on IBD risk and gut health.

Maternal diet in pregnancy and the risk of inflammatory bowel disease in the offspring: a prospective cohort study

BACKGROUND

Diet has been hypothesized as a risk factor for the development of inflammatory bowel disease (IBD).

OBJECTIVE

The objective of this study was to explore associations between maternal diet diversity and quality in pregnancy and the offspring's risk of IBD.

METHODS

We used data from a nationwide cohort study on 85,129 Norwegian children followed from birth (1999-2009) with information on maternal diet in pregnancy from validated food frequency questionnaires. Hazard ratios (HRs) for IBD, Crohn disease (CD), and ulcerative colitis (UC) by maternal diet diversity, quality, and intake amounts of individual food groups were adjusted for maternal BMI, parental IBD, and sociodemographic factors. Sensitivity analyses were adjusted for the child's early-life diet quality and antibiotic treatment. Dietary exposures were classified into tertiles, comparing low (reference) with medium, and high levels.

RESULTS

During a mean follow-up time of 16.1 y (1,367,837 person-years of follow-up), 268 children developed IBD (CD, n = 119; UC, n = 76; IBD-unclassified, n = 73). High compared with low diet diversity in pregnancy was associated with a lower risk of UC in the offspring [adjusted HR (aHR) 0.46, 95% confidence interval: 0.25, 0.87], with consistent findings after further adjustment for the child's early-life diet quality and antibiotic treatment. High compared with low diet diversity in pregnancy yielded aHRs of 0.81 for CD (0.51-1.28) and 0.75 for any IBD (0.55-1.02) in the offspring. A high compared with low diet quality in pregnancy or intakes of specific food groups were not associated with the offspring's risk of IBD or its subtypes.

CONCLUSIONS

Our findings suggest that a higher maternal diet diversity in pregnancy may be associated with a lower risk of UC in the offspring.

The Role of Diet in Inflammatory Bowel Disease Onset, Disease Management, and Surgical Optimization

The concept of using diet as therapy in inflammatory bowel disease is of interest to clinicians and patients. Once considered to play a minor role, diet is now known to not only affect disease onset but may also serve as a therapeutic tool for inducing and maintaining remission and improving surgical outcomes. Further research is needed to fully elucidate how, when, and in whom diet therapies may be best applied to improve clinical and disease outcomes. The aim of this review was to summarize current research findings and serve as a tool to help facilitate patient-clinician conversations.

Effects of an anti-inflammatory diet (AID) on maternal and neonatal health outcomes in pregnant Chinese patients with inflammatory bowel disease treated with infliximab (IFX)

OBJECTIVE

This study aimed to evaluate the effects of an anti-inflammatory diet (AID) combined with Infliximab (IFX) therapy on maternal and neonatal health outcomes in pregnant Chinese patients with inflammatory bowel disease (IBD).

METHODS

IBD patients treated with steady IFX maintenance therapy at the time of conception were randomly assigned to either the IBD-AID group (n = 49), which received an anti-inflammatory diet intervention during the third trimester, or the habitual diet group (n = 49). Primary outcomes included assessments of disease activity, inflammatory markers, and neonatal health. Secondary outcomes included health-related quality of life (HRQoL) in patients and functional gastrointestinal disorders (FGIDs) in infants.

RESULTS

The IBD-AID intervention significantly reduced disease activity scores in IBD patients at 4 weeks post-intervention and 1 month postpartum compared to the habitual diet group, and also improved HRQoL. Serum C-reactive protein (CRP) and fecal calprotectin (FC) levels were significantly lower in the IBD-AID group at these times, with a trend towards lower levels at 6 months postpartum. Birth weight and Apgar scores were higher in the IBD-AID group but did not reach statistical significance. The incidence of at least one FGID in infants was significantly lower in the IBD-AID group (24.5%) compared to the habitual diet group (46.9%, p = 0.034).

CONCLUSION

The IBD-AID intervention combined with IFX therapy significantly improved disease activity, inflammatory markers, and QoL in maternal IBD patients, and was associated with a lower incidence of FGIDs in infants, indicating benefits for both maternal and neonatal health.

Challenges in IBD Research 2024: Environmental Triggers

Environmental factors play an important role in inflammatory bowel diseases (IBD; Crohn's disease, [CD], ulcerative colitis [UC]). As part of the Crohn's & Colitis Challenges 2024 agenda, the Environmental Triggers workgroup summarized the progress made in the field of environmental impact on IBD since the last Challenges cycle in this document. The workgroup identified 4 unmet gaps in this content area pertaining to 4 broad categories: (1) Epidemiology; (2) Exposomics and environmental measurement; (3) Biologic mechanisms; and (4) Interventions and Implementation. Within epidemiology, the biggest unmet gaps were in the study of environmental factors in understudied populations including racial and ethnic minority groups and in populations witnessing rapid rise in disease incidence globally. The workgroup also identified a lack of robust knowledge of how environmental factors may impact difference stages of the disease and for different disease-related end points. Leveraging existing cohorts and targeted new prospective studies were felt to be an important need for the field. The workgroup identified the limitations of traditional questionnaire-based assessment of environmental exposure and placed high priority on the identification of measurable biomarkers that can quantify cross-sectional and longitudinal environmental exposure. This would, in turn, allow for identifying the biologic mechanisms of influence of environmental factors on IBD and understand the heterogeneity in effect of such influences. Finally, the working group emphasized the importance of generating high-quality data on effective environmental modification on an individual and societal level, and the importance of scalable and sustainable methods to deliver such changes.

Early-life exposures and the microbiome: implications for IBD prevention

The early-life period is one of microbiome establishment and immune maturation. Early-life exposures are increasingly being recognised to play an important role in IBD risk. The composition of functions of the gut microbiome in the prenatal, perinatal, and postnatal period may be crucial towards development of health or disease, including IBD, later in life. We herein present a comprehensive summary of the interplay between early-life factors and microbiome perturbations, and their association with risk of IBD. In addition, we provide an overview of host and external factors in early life that are known to impact gut microbiome maturation and exposures implicated in IBD risk. Considering the emerging concept of IBD prevention, we propose strategies to minimise maternal and offspring exposure to potentially harmful variables and recommend protective measures during pregnancy and the postpartum period. This holistic view of early-life factors and microbiome signatures among mothers and their offspring will help frame our current understanding of their importance towards IBD pathogenesis and frame the roadmap for preventive strategies.

Metabolomics and lipidomics strategies in modern drug discovery and development

Metabolomics and lipidomics have an increasingly pivotal role in drug discovery and development. In the context of drug discovery, monitoring changes in the levels or composition of metabolites and lipids relative to genetic variations yields functional insights, bolstering human genetics and (meta)genomic methodologies. This approach also sheds light on potential novel targets for therapeutic intervention. In the context of drug development, metabolite and lipid biomarkers contribute to enhanced success rates, promising a transformative impact on precision medicine. In this review, we deviate from analytical chemist-focused perspectives, offering an overview tailored to drug discovery. We provide introductory insight into state-of-the-art mass spectrometry (MS)-based metabolomics and lipidomics techniques utilized in drug discovery and development, drawing from the collective expertise of our research teams. We comprehensively outline the application of metabolomics and lipidomics in advancing drug discovery and development, spanning fundamental research, target identification, mechanisms of action, and the exploration of biomarkers.

ietanti-flamatoria or DAIN: A Crohn's disease management strategy tailored for Puerto Ricans

Diet has been increasingly shown to be of therapeutic benefit for patients with inflammatory bowel diseases (IBD), especially Crohn's disease (CD). Yet dietary guidelines are nonexistent. Moreover, diets tailored to Puerto Ricans with IBD living on the island, have not been developed and tested. The rising prevalence of IBD in Puerto Rico warrants exploring the use of diet as part of the treatment strategies for these patients [1]. Here, we describe the study design of "Dieta Anti-Inflamatoria" or DAIN, a parallel two-arm randomized pilot trial aiming at testing the efficacy of IBD-Anti-inflammatory diet (IBD-AID) adapted for adults with CD living in Puerto Rico (clinical trial registration number: NCT05627128). We tailored the IBD-AID to the local cuisine preferences and food availability by creating and adapting recipes consistent with the IBD-AID principles [2,3]. In focus groups with a Community Research Advisory Panel and one-on-one consultations with implementation experts, we identified several aspects of the intervention to adapt before the implementation. The objectives of the stakeholder/expert-informed adaptation were to improve feasibility and compliance while developing the culturally tailored dietary intervention. DAIN was designed for adults living in Puerto Rico with CD and geared to be affordable, appropriate, and acceptable for patients with mild-to-moderate CD. The significance of this work is the validation of culturally appropriate nutritional guidelines to help manage CD symptoms. DAIN provides a blueprint for a comprehensive nutritional program that can be adapted to regional preferences and local food availability allowing wider implementation of diet as an adjunct treatment in diverse clinical settings.

The microbiota of pregnant women with SARS-CoV-2 and their infants

BACKGROUND

Infants receive their first bacteria from their birthing parent. This newly acquired microbiome plays a pivotal role in developing a robust immune system, the cornerstone of long-term health.

RESULTS

We demonstrated that the gut, vaginal, and oral microbial diversity of pregnant women with SARS-CoV-2 infection is reduced, and women with early infections exhibit a different vaginal microbiota composition at the time of delivery compared to their healthy control counterparts. Accordingly, a low relative abundance of two Streptococcus sequence variants (SV) was predictive of infants born to pregnant women with SARS-CoV-2 infection.

CONCLUSIONS

Our data suggest that SARS-CoV-2 infections during pregnancy, particularly early infections, are associated with lasting changes in the microbiome of pregnant women, compromising the initial microbial seed of their infant. Our results highlight the importance of further exploring the impact of SARS-CoV-2 on the infant's microbiome-dependent immune programming. Video Abstract.

Dietary Intake of Pregnant Women with and without Inflammatory Bowel Disease in the United States

BACKGROUND

Pregnancy is a vulnerable time where the lives of mother and baby are affected by diet, especially high-risk pregnancies in women with inflammatory bowel disease (IBD). Limited research has examined diet during pregnancy with IBD.

AIMS

Describe and compare the diet quality of pregnant women with and without IBD, and examine associations between dietary intake and guidelines during pregnancy.

METHODS

Three 24 h recalls were utilized to assess the diets of pregnant women with IBD (n = 88) and without IBD (n = 82) during 27-29 weeks of gestation. A customized frequency questionnaire was also administered to measure pre- and probiotic foods.

RESULTS

Zinc intake (p = 0.02), animal protein (g) (p = 0.03), and ounce equivalents of whole grains (p = 0.03) were significantly higher in the healthy control (HC) group than the IBD group. Nutrients of concern with no significant differences between groups included iron (3% IBD and 2% HC met the goals), saturated fat (only 1% of both groups met the goals), choline (23% IBD and 21% HC met the goals), magnesium (38% IBD and 35% HC met the goals), calcium (48% IBD and 60% HC met the goals), and water intake (49% IBD and 48% HC met the goals).

CONCLUSIONS

Most pregnant women in this cohort fell short of the dietary nutrients recommended in pregnancy, especially concerning for women with IBD.

Maternal Mental Health and Offspring Brain Development: An Umbrella Review of Prenatal Interventions

The idea that risk for psychiatric disorders may be transmitted intergenerationally via prenatal programming places interest in the prenatal period as a critical moment during which intervention efforts may have a strong impact, yet studies testing whether prenatal interventions also protect offspring are limited. The present umbrella review of systematic reviews and meta-analyses (SRMAs) of randomized controlled trials aimed to synthesize the available evidence and highlight promising avenues for intervention. Overall, the literature provides mixed and limited evidence in support of prenatal interventions. Thirty SRMAs were included. Of the 23 SRMAs that reported on prenatal depression interventions, 16 found a significant effect (average standard mean difference = -0.45, SD = 0.25). Similarly, 13 of the 20 SRMAs that reported on anxiety outcomes documented significant reductions (average standard mean difference = -0.76, SD = 0.95 or -0.53/0.53 excluding one outlier). Only 4 SRMAs reported child outcomes, and only 2 (of 10) analyses showed significant effects of prenatal interventions (massage and telephone support on neonatal resuscitation [relative risk = 0.43] and neonatal intensive care unit admissions [relative risk = 0.91]). Notably missing, perhaps due to our strict inclusion criteria (inclusion of randomized controlled trials only), were interventions focusing on key facets of prenatal health (e.g., whole diet, sleep). Structural interventions (housing, access to health care, economic security) were not included, although initial success has been documented in non-SRMAs. Most notably, none of the SRMAs focused on offspring mental health or neurodevelopmental outcomes. Given the possibility that interventions deployed in this period will positively impact the next generation, randomized trials that focus on offspring outcomes are urgently needed.

Breastfeeding Is Associated with Lower Likelihood of Helicobacter Pylori Colonization in Babies, Based on a Prospective USA Maternal-Infant Cohort

BACKGROUND

Mother-to-child transmission of Helicobacter pylori (H. pylori) is the primary source of intrafamilial spread in early childhood in regions of high H. pylori prevalence. However, early-in-life H. pylori colonization and associated protective or risk factors have not been fully evaluated in lower prevalence regions, such as the USA.

AIMS

Therefore, from a well-characterized prospective US cohort, we selected women who provided fecal samples during pregnancy and had paired fecal samples from their babies up to 24 months postpartum. We evaluated maternal and baby factors associated with likelihood of H. pylori colonization in the babies. Fecal antigen testing was used to determine H. pylori status. We also evaluated the association between maternal breastmilk cytokines and H. pylori colonization in breastfed babies.

RESULTS

Among included mother-baby pairs (n = 66), H. pylori prevalence was 31.8% in mothers and 19.7% in their babies. Dominant breastfeeding (adjusted odds ratio [aOR] 0.17, 95% CI 0.03-0.98) and maternal IBD (aOR 0.05, 95% CI 0.01-0.27) were associated with significantly lower likelihood of H. pylori colonization among babies; no other clinical factors were associated with H. pylori colonization in the babies. Matrix metalloproteinase-10 (MMP-10) and tumor necrosis factor-related activation-induced cytokine expression were significantly higher in breastmilk of mothers with H. pylori positive vs negative babies.

CONCLUSIONS

Consistent with data from high H. pylori prevalence regions, our findings suggest dominant breastfeeding may protect against early H. pylori colonization. Downregulation of pro-inflammatory cytokines such as MMP-10 may be relevant in mediating this protection among breastfed babies, but more data are needed.

A Review on Inflammatory Bowel Diseases: Recent Molecular Pathophysiology Advances

Inflammatory bowel diseases are considered immune disorders with a complex genetic architecture involving constantly changing endogenous and exogenous factors. The rapid evolution of genomic technologies and the emergence of newly discovered molecular actors are compelling the research community to reevaluate the knowledge and molecular processes. The human intestinal tract contains intestinal human microbiota consisting of commensal, pathogenic, and symbiotic strains leading to immune responses that can contribute and lead to both systemic and intestinal disorders including IBD. In this review, we attempted to highlight some updates of the new IBD features related to genomics, microbiota, new emerging therapies and some major established IBD risk factors.

Food as Treatment of Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD), namely, Crohn's disease (CD) and ulcerative colitis (UC), are lifelong and incurable chronic inflammatory diseases affecting 6.8 million people worldwide. By 2030, the prevalence of IBD is estimated to reach 1% of the population in Western countries, and thus there is an urgent need to develop effective therapies to reduce the burden of this disease. Microbiome dysbiosis is at the heart of the IBD pathophysiology, and current research and development efforts for IBD treatments have been focused on gut microbiome regulation. Diet can shape the intestinal microbiome. Diet is also preferred over medication, is safe, and has been proven to be an effective strategy for the management of IBD. Therefore, although often overlooked, dietary interventions targeting the microbiome represent ideal treatments for IBD. Here, I summarize the latest research on diet as a treatment for IBD from infancy to adulthood, compile evidence of the mechanisms of action behind diet as treatment, and, lastly, provide insights into future research focusing on culturally tailored diets for ethnic minority groups with increased incidence of IBD yet underrepresented in nutrition research.

Dietary manipulation of the gut microbiome in inflammatory bowel disease patients: Pilot study

Diet is a modifiable, noninvasive, inexpensive behavior that is crucial in shaping the intestinal microbiome. A microbiome "imbalance" or dysbiosis in inflammatory bowel disease (IBD) is linked to inflammation. Here, we aim to define the impact of specific foods on bacterial species commonly depleted in patients with IBD to better inform dietary treatment. We performed a single-arm, pre-post intervention trial. After a baseline period, a dietary intervention with the IBD-Anti-Inflammatory Diet (IBD-AID) was initiated. We collected stool and blood samples and assessed dietary intake throughout the study. We applied advanced computational approaches to define and model complex interactions between the foods reported and the microbiome. A dense dataset comprising 553 dietary records and 340 stool samples was obtained from 22 participants. Consumption of prebiotics, probiotics, and beneficial foods correlated with increased abundance of Clostridia and Bacteroides, commonly depleted in IBD cohorts. We further show that specific foods categorized as prebiotics or adverse foods are correlated to levels of cytokines in serum (i.e., GM-CSF, IL-6, IL-8, TNF-alpha) that play a central role in IBD pathogenesis. By using robust predictive analytics, this study represents the first steps to detangle diet-microbiome and diet-immune interactions to inform personalized nutrition for patients suffering from dysbiosis-related IBD.

The Concept of Intrauterine Programming and the Development of the Neonatal Microbiome in the Prevention of SARS-CoV-2 Infection

The process of intrauterine programming is related to the quality of the microbiome formed in the fetus and the newborn. The implementation of probiotics, prebiotics, and psychobiotics shows immunomodulatory potential towards the organism, especially the microbiome of the pregnant woman and her child. Nutrigenomics, based on the observation of pregnant women and the developing fetus, makes it possible to estimate the biological effects of active dietary components on gene expression or silencing. Nutritional intervention for pregnant women should consider the nutritional status of the patient, biological markers, and the potential impact of dietary intervention on fetal physiology. The use of a holistic model of nutrition allows for appropriately targeted and effective dietary prophylaxis that can impact the physical and mental health of both the mother and the newborn. This model targets the regulation of the immune response of the pregnant woman and the newborn, considering the clinical state of the microbiota and the pathomechanism of the nervous system. Current scientific reports indicate the protective properties of immunobiotics (probiotics) about the reduction of the frequency of infections and the severity of the course of COVID-19 disease. The aim of this study was to test the hypothesis that intrauterine programming influences the development of the microbiome for the prevention of SARS-CoV-2 infection based on a review of research studies.

Inflammatory Bowel Disease and Reproductive Health: From Fertility to Pregnancy-A Narrative Review

Despite the fact that knowledge on obstetrical management of Inflammatory Bowel Diseases (IBDs) has greatly improved over the years, many patients still actively avoid pregnancy for fear of adverse maternal or neonatal outcomes, of adverse effects of pregnancy on the disease activity, of eventual IBD inheritance, or of an increased risk of congenital malformations. Indeed, though data prove that fertility is hardly affected by the disease, a reduced birth rate is nevertheless observed in patients with IBD. Misconceptions on the safety of drugs during gestation and breastfeeding may influence patient choice and negatively affect their serenity during pregnancy or lactation. Moreover, physicians often showed concerns about starting IBD medications before and during pregnancy and did not feel adequately trained on the safety of IBD therapies. IBD-expert gastroenterologists and gynecologists should discuss pregnancy and breastfeeding issues with patients when starting or changing medications in order to provide appropriate information; therefore, pre-conception counselling on an individualized basis should be mandatory for all patients of reproductive age to reassure them that maintaining disease remission and balancing the eventual obstetrical risks is possible.

Dietary Patterns and Gut Microbiota: The Crucial Actors in Inflammatory Bowel Disease

It is widely believed that diet and the gut microbiota are strongly related to the occurrence and progression of inflammatory bowel disease (IBD), but the effects of the interaction between dietary patterns and the gut microbiota on IBD have not been well elucidated. In this article, we aim to explore the complex relation between dietary patterns, gut microbiota, and IBD. We first comprehensively summarized the dietary patterns associated with IBD and found that dietary patterns can modulate the occurrence and progression of IBD through various signaling pathways, including mammalian target of rapamycin (mTOR), mitogen-activated protein kinases (MAPKs), signal transducer and activator of transcription 3 (STAT3), and NF-κB. Besides, the gut microbiota performs a vital role in the progression of IBD, which can affect the expression of IBD susceptibility genes, such as dual oxidase 2 (DUOX2) and APOA-1 , the intestinal barrier (in particular, the expression of tight junction proteins), immune function (especially the homeostasis between effector and regulatory T cells) and the physiological metabolism, in particular, SCFAs, bile acids (BAs), and tryptophan metabolism. Finally, we reviewed the current knowledge on the interaction between dietary patterns and the gut microbiota in IBD and found that dietary patterns modulate the onset and progression of IBD, which is partly attributed to the regulation of the gut microbiota (especially SCFAs-producing bacteria and Escherichia coli). Faecalibacteria as "microbiomarkers" of IBD could be used as a target for dietary interventions to alleviate IBD. A comprehensive understanding of the interplay between dietary intake, gut microbiota, and IBD will facilitate the development of personalized dietary strategies based on the regulation of the gut microbiota in IBD and expedite the era of precision nutritional interventions for IBD.

Results of the Seventh Scientific Workshop of ECCO: Precision Medicine in IBD-Prediction and Prevention of Inflammatory Bowel Disease

Inflammatory bowel disease [IBD] is a complex chronic disorder with no clear aetiology and no known cure. Despite recent advances in overall disease management and improved therapeutics, patients with IBD still experience a substantial burden. Furthermore, as the incidence continues to increase in developing areas of the world, it is expected that the burden of IBD to society will increase and exert tremendous pressure on health care systems worldwide. Therefore, new strategies to prevent the global increase of IBD are urgently required. Data are being progressively acquired on the period preceding disease diagnosis, which support the concept that IBD has a preclinical period that may reveal the triggers of disease and may be amenable to early intervention. Having a better knowledge of this preclinical period will increase the potential not only for improved understanding of disease pathogenesis and improved therapeutics, but also for disease prediction and prevention.

The role of precision nutrition in the modulation of microbial composition and function in people with inflammatory bowel disease

Inflammatory bowel diseases, principally Crohn's disease and ulcerative colitis, are multifactorial chronic conditions. Alterations in gut microbial patterns partly affect disease onset and severity. Moreover, the evolution of dietary patterns, and their effect on gut microbial behaviour, have been shown to play a crucial role in disease processes. This Viewpoint reviews the role of dietary patterns, their influence on the structure and function of the gut microbiome, and their effects on inflammation and immunity in individuals with inflammatory bowel disease. We also discuss innovative dietary intervention strategies, summarise findings that have been used to develop recommendations for clinical practice, and provide suggestions for the design of future studies for development of precision nutrition in patients with inflammatory bowel disease.

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.