Co-occurrence of Asthma and the Inflammatory Bowel Diseases: A Systematic Review and Meta-analysis

A mode of action protein based approach that characterizes the relationships among most major diseases

Disease classification is important for understanding disease commonalities on both the phenotypical and molecular levels. Based on predicted disease mode of action (MOA) proteins, our algorithm PICMOA (Pan-disease Classification in Mode of Action Protein Space) classifies 3526 diseases across 20 clinically classified classifications (ICD10-CM major classifications). At the top level, all diseases can be classified into "infectious" and "non-infectious" diseases. Non-infectious diseases are classified into 9 classes. To demonstrate the validity of the classifications, for common pathways predicted based on MOA proteins, 77% of the top 10 most frequent pathways have literature evidence of association to their respective disease classes/subclasses. These results indicate that PICMOA will be useful for understanding common disease mechanisms and facilitating the development of drugs for a class of diseases, rather than a single disease. The MOA proteins, molecular functions, pathways for classes, and individual diseases are available at https://sites.gatech.edu/cssb/PICMOA/ .

Risk factors for inflammatory bowel disease: an umbrella review

Introduction

Inflammatory bowel disease (IBD) represents a cluster of chronic idiopathic inflammatory disorders situated at the nexus of intricate interplays. The primary aim of the present investigation is to perform an umbrella review of metaanalyses, systematically offering a comprehensive overview of the evidence concerning risk factors for IBD.

Methods

To achieve this, we searched reputable databases, including PubMed, Embase, Web of Science, and the Cochrane Database of Systematic Reviews, from inception through April 2023. Two authors independently assessed the methodological quality of each metaanalysis using the AMSTAR tool and adhered to evidence classification criteria.

Results

In total, we extracted 191 unique risk factors in meta-analyses, including 92 significantly associated risk factors. The top ten risk factors were human cytomegalovirus (HCMV) infection, IBD family history, periodontal disease, poliomyelitis, campylobacter species infection, hidradenitis suppurativa, psoriasis, use of proton pump inhibitors, chronic obstructive pulmonary disease, and western dietary pattern.

Discussion

In conclusion, this umbrella review extracted 62 risk factors and 30 protective factors, most of which were related to underlying diseases, personal lifestyle and environmental factors. The findings in this paper help to develop better prevention and treatment measures to reduce the incidence of IBD, delay its progression, and reduce the burden of IBD-related disease worldwide.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023417175.

Association between allergic diseases and mucosal healing in ulcerative colitis

Allergic diseases and ulcerative colitis (UC) share pathophysiological similarities. This study aimed to investigate the unclear association between allergic diseases and mucosal healing (MH), an important factor in the prognosis of UC. We studied 289 Japanese patients with UC. Information on allergic diseases (bronchial asthma, atopic dermatitis, pollen allergy, food allergy, and drug allergy), as diagnosed by physicians, was collected through self-reported questionnaires. The definition of MH was Mayo Endoscopic Score 0. The association between each allergic disease and its multimorbidity with MH was evaluated using multivariate logistic regression analyses. Pollen allergy was the most common allergic condition (36.3%). Pollen allergy and food allergy were independently associated with MH (pollen allergy adjusted OR: 1.82 [95% CI: 1.01-3.26]; food allergy adjusted OR: 3.47 [95% CI: 1.26-9.68]). The rates of MH for 0 and 3 or more allergic diseases were 24.6% and 4.2%, respectively. After adjustment for confounders, 3 or more allergic diseases were independently associated with MH (adjusted OR: 8.13 [95% CI: 2.17-34.04], p for trend = 0.020). This study demonstrates a significant positive association between specific allergic diseases (pollen and food allergies) and MH in UC patients, with a stronger association in cases of allergic multimorbidity.

Increased Risk of Chronic Respiratory Disease among Individuals with Inflammatory Bowel Disease in a Prospective Cohort Study

BACKGROUND

Cross-sectional evidence suggests a higher burden of chronic respiratory diseases in people with inflammatory bowel disease, but there is a lack of prospective evidence to clarify the direction of their associations. We aimed to investigate the association of inflammatory bowel disease with the risk of 2 major chronic respiratory diseases, chronic obstructive pulmonary disease, and asthma.

METHODS

We included 430,414 participants from UK Biobank and followed them from recruitment (2006-2010) to 2021. Chronic obstructive pulmonary disease and asthma cases were obtained from inpatient data and death register. Using Cox proportional hazards models, we estimated the multivariable-adjusted hazard ratios (HR) of developing chronic obstructive pulmonary disease and asthma in participants with inflammatory bowel disease compared with inflammatory bowel disease-free groups. We also investigated the association among Crohn's disease and ulcerative colitis with the risk of chronic obstructive pulmonary disease and asthma.

RESULTS

Over a median follow-up of 11.9 years, there were 11,196 incidents of chronic obstructive pulmonary disease and 9831 asthma cases. The adjusted HRs of developing chronic obstructive pulmonary disease (HR 1.54; 95% confidence interval [CI], 1.33-1.79) and asthma (HR 1.52; 95% CI, 1.29-1.79) were higher for those with inflammatory bowel disease when compared with inflammatory bowel disease-free participants. Participants with Crohn's disease and ulcerative colitis were also found to have a higher risk of chronic obstructive pulmonary disease (Crohn's disease: HR 1.71; 95% CI, 1.36-2.15; ulcerative colitis: HR 1.45; 95% CI, 1.20-1.75) and asthma (Crohn's disease: HR 1.73; 95% CI, 1.33-2.25; ulcerative colitis: HR 1.41; 95% CI, 1.15-1.73) when compared with those free of inflammatory bowel disease.

CONCLUSIONS

This study suggested that individuals with inflammatory bowel disease have a higher risk of developing chronic obstructive pulmonary disease and asthma, highlighting the importance of preventing chronic respiratory diseases among inflammatory bowel disease patients.

FABIO: TWAS fine-mapping to prioritize causal genes for binary traits

Transcriptome-wide association studies (TWAS) have emerged as a powerful tool for identifying gene-trait associations by integrating gene expression mapping studies with genome-wide association studies (GWAS). While most existing TWAS approaches focus on marginal analyses through examining one gene at a time, recent developments in TWAS fine-mapping methods enable the joint modeling of multiple genes to refine the identification of potentially causal ones. However, these fine-mapping methods have primarily focused on modeling quantitative traits and examining local genomic regions, leading to potentially suboptimal performance. Here, we present FABIO, a TWAS fine-mapping method specifically designed for binary traits that is capable of modeling all genes jointly on an entire chromosome. FABIO employs a probit model to directly link the genetically regulated expression (GReX) of genes to binary outcomes while taking into account the GReX correlation among all genes residing on a chromosome. As a result, FABIO effectively controls false discoveries while offering substantial power gains over existing TWAS fine-mapping approaches. We performed extensive simulations to evaluate the performance of FABIO and applied it for in-depth analyses of six binary disease traits in the UK Biobank. In the real datasets, FABIO significantly reduced the size of the causal gene sets by 27.9%-36.9% over existing approaches across traits. Leveraging its improved power, FABIO successfully prioritized multiple potentially causal genes associated with the diseases, including GATA3 for asthma, ABCG2 for gout, and SH2B3 for hypertension. Overall, FABIO represents an effective tool for TWAS fine-mapping of disease traits.

Prevalence of bronchiectasis in inflammatory bowel disease: a systematic review and meta-analysis

Objective

The aim of this study was to conduct a systematic review and meta-analysis of the incidence of inflammatory bowel disease-associated bronchiectasis (IBD-BE) and to explore the possible risk factors for IBD-BE, which could help to understand the pulmonary involvement in patients with IBD and to determine the global incidence of the disease.

Methods

We searched PubMed and EMBASE databases to identify information on the prevalence of IBD-BE among IBD patients in the published literature. Information was extracted on study design, country, year, IBD-BE testing method, IBD characteristics, number of IBD-BE cases and total number of IBD patients, and factors associated with IBD-BE. We conducted meta-analyses using random-effects or fixed-effects models to estimate the prevalence of IBD-BE among IBD patients.

Results

Out of a total of 682 studies, we identified 16 studies that reported prevalence. These studies used a heterogeneous approach to identify IBD-BE. In these 16 studies, there were 92,191 patients with IBD, of whom 372 cases of IBD-BE were identified. The results of the meta-analysis showed that the overall prevalence of IBD-BE in IBD derived from the use of a random effects model was 5.0% (95% CI 2.0-12.0%). In contrast, the prevalence of IBD-BE in studies using high-resolution chest computed tomography (HRCT) imaging was 12% (95% CI 4-39%) using a random-effects model. When only retrospective studies with sample sizes greater than 100 (n = 6) were considered, the prevalence was 1% (95% CI 0-1%). However, when only retrospective studies with sample sizes less than 100 were included (n = 4), the prevalence was 29% (95% CI 6-100%); in prospective studies (n = 6), the combined prevalence was 11% (95% CI 4-29%). we performed a subgroup analysis of the differences in the incidence of IBD-BE between the different studies, each of which we subgrouped by type of study, type of disease, duration of disease, and diagnostic modality, and the results showed no significance. Future studies should standardize methods to identify IBD-BE cases and investigate the natural history and clinical course given the relatively high prevalence among IBD.

Conclusion

In this systematic review and meta-analysis, the prevalence of IBD-BE was 12% among studies with HRCT imaging, suggesting that bronchiectasis may be an underestimated common extraintestinal manifestation of IBD. Asymptomatic patients with IBD-BE may present with abnormalities on HRCT or pulmonary function tests. Future studies should standardize methods to identify IBD-BE cases and investigate the natural history and clinical course given the relatively high prevalence among IBD.

Atopic disease and inflammatory bowel disease: A bidirectional Mendelian randomization study

Observational studies have reported associations between atopic diseases, including allergic rhinitis (AR), asthma, atopic dermatitis (AD), and inflammatory bowel disease (IBD), but the causal relationship remains unknown. We utilized pooled data from genome-wide association studies, qualified instrumental variables were screened according to the 3 hypotheses of MR, and bidirectional causality between atopic diseases and IBD was assessed using 2-sample Mendelian randomization analysis (2SMR). The results of our study suggest that AR increased the risk of Crohn disease (CD) (IVW OR = 1.19, 95% CI = 1.02-1.39, P = .026), ulcerative colitis (UC) (IVW OR = 1.14, 95% CI = 1.01-1.29, P = .031) and overall IBD (IVW OR = 1.15, 95% CI = 1.03-1.28, P = .015); Asthma increased the risk of CD (IVW OR = 7.66, 95% CI = 1.58-37.20, P = .012), UC (IVW OR = 3.81, 95% CI = 1.09-13.32, P = .036) and overall IBD (IVW OR = 5.13, 95% CI = 1.48-17.70, P = .010); AD increased the risk of CD (IVW OR = 1.19, 95% CI = 1.02-1.39, P = .023) and overall IBD (IVW OR = 1.14, 95% CI = 1.03-1.28, P = .015) risk. In reverse causality, only CD increased the risk of AR (IVW OR = 1.02, 95% CI = 1.00-1.05, P = .031). This study shows that atopic diseases of AR and asthma are causally related to IBD and its subtypes, and AD is causally related to IBD (which may be attributed to CD). Of the reverse causality, only CD was causally related to AR.

Combination treatment with monoclonal antibodies for the management of severe asthma and immune-mediated inflammatory diseases: a comprehensive review

Biological drugs have revolutionized the management of severe asthma, and a tailored treatment approach made it possible to consider remission as an achievable treatment target. The incidence of autoimmune diseases is increasing in many parts of the world. Patients suffering from severe asthma, eligible or already treated with an asthma-approved biologic agent, may suffer from another immune-mediated inflammatory disease (IMID) that could require the simultaneous use of a second monoclonal antibody. The real-life studies available in the literature describing the concurrent administration of an asthma-approved biologic agent with another biologic for a different immune disease, obtained through a systematic search on online databases based on monoclonal antibodies, were collected and analyzed. 26 articles were included in this review according to the prespecified inclusion and exclusion criteria. All included papers were retrospective in nature. Study designs were case reports (n=18), case series (n=3), retrospective chart reviews (n=3), retrospective observational studies (n=1), and cohort studies (n=1). The study is intended to present, within the current literature, all the administered combinations of severe asthma-approved biologics with monoclonal antibodies for a different indication. Those were grouped according to the IMID for whom the second biologic agent, with a different mechanism of action, was prescribed. The combinations prescribed to the cohort of patients specifically treating uncontrolled severe asthma were deeper evaluated in the discussion section, since an analysis of these therapeutic combinations deriving from real-life experiences may be useful to optimize the management of patients with severe asthma, ultimately leading to improved patient care and outcomes. Prospective registries and future studies are required to assess the safety and efficacy of combination therapies for severe asthmatic patients who suffer from an IMID.

Pulmonary Manifestations of IBD: Case Report and Review of the Literature

This article explores the pulmonary complications associated with inflammatory bowel disease (IBD). It presents a detailed case study of a 22-year-old male with Crohn's disease exhibiting pulmonary symptoms. The review delves into the spectrum of pulmonary involvement in IBD, covering clinical presentations, diagnostic challenges, underlying pathophysiology, and management strategies. It highlights the significance of these extraintestinal manifestations on patient outcomes and quality of life. The article underscores the need for heightened clinical awareness and a systematic approach to diagnosis and management, integrating the expertise of multiple specialists. The review identifies gaps in current research, suggesting avenues for future investigation to enhance the understanding and treatment of these complex manifestations.

Comorbidity Between Inflammatory Bowel Disease and Asthma and Allergic Diseases: A Genetically Informed Study

BACKGROUND

Little is known about shared origins between inflammatory bowel disease (IBD) and allergic diseases (asthma, allergic rhinitis, and eczema). We aimed to expand current knowledge on the etiological sources of comorbidities between these disorders using a range of genetically informed methods.

METHODS

Within-individual and familial co-aggregation analysis was applied to 2 873 445 individuals born in Sweden from 1987 to 2014 and their first- and second-degree relatives. Quantitative genetic modeling was applied to 38 723 twin pairs to decompose the genetic and environmental sources for comorbidity. Polygenic risk score analysis between IBD and allergic diseases was conducted in 48 186 genotyped twins, and linkage disequilibrium score regression was applied using publicly available data to explore the genetic overlap.

RESULTS

IBD was associated with asthma (adjusted odds ratio [aOR], 1.35; 95% confidence interval [CI], 1.30 to 1.40), allergic rhinitis (aOR, 1.27; 95% CI, 1.20 to 1.34), and eczema (aOR, 1.47; 95% CI, 1.38 to 1.56), with similar estimates for ulcerative colitis or Crohn's disease. The ORs for familial co-aggregation decreased with decreasing genetic relatedness. Quantitative genetic modeling revealed little evidence of common genetic factors between IBD and allergic diseases (eg, IBD and allergic rhinitis; genetic correlation ra = 0.06; 95% CI, -0.03 to 0.15) but did reveal some evidence of unique environmental factors between IBD and eczema (re = 0.16; 95% CI, 0.00 to 0.32). Molecular genetic analyses were similarly null for IBD and allergic diseases, except for a slight association between Crohn's disease polygenic risk score and eczema (OR, 1.09; 95% CI, 1.06 to 1.12).

CONCLUSIONS

We found little evidence to support a shared origin between IBD and any allergic disease but weak evidence for shared genetic and unique environmental components for IBD and eczema.

Pediatric asthma comorbidities: Global impact and unmet needs

Real-world data on the range and impact of comorbid health conditions that affect pediatric asthma are scant, especially from developing countries. Lack of data hinders effective diagnosis, treatment, and overall management of these complex cases. We, hereby, describe the common pediatric asthma comorbid conditions in terms of evidence for association, potential mechanisms of impact on asthma control, and treatment benefit. Obesity, upper airway allergies, dysfunctional breathing, multiple sensitizations, depressive disorders, food allergy, and gastro-esophageal reflux are common associations with difficult-to-treat asthma. On the other hand, asthma symptoms and/or management may negatively impact the well-being of children through drug adverse effects, worsening of anaphylaxis symptoms, and disturbing mental health. Awareness of these ailments may be crucial for designing the optimum care for each asthmatic child individually and may ultimately improve the quality of life of patients and their families. A multidisciplinary team of physicians is required to identify and manage such comorbidities aiming to mitigate the over-use of asthma pharmacotherapy. Asthma research should target relevant real-world difficulties encountered at clinical practice and focus on interventions that would mitigate the impact of such comorbidities. Finally, policymakers and global healthcare organizations are urged to recognize pediatric asthma control as a healthcare priority and allocate resources for research and clinical interventions. In other words, global asthma control needs support by compassionate scientific partnership.

Dermatologic manifestations in pediatric patients with inflammatory bowel disease

BACKGROUND

Despite studies of dermatologic manifestations in adults with inflammatory bowel disease (IBD), little is known about the prevalence of IBD-associated skin lesions and their correlation with IBD severity in children. We aimed to address these knowledge gaps in our single-center cohort of children with IBD.

METHODS

Retrospective chart review of 528 children and adolescents (≤18 years old) with IBD and seen at Mayo Clinic (Rochester, MN) between 1999 and 2017 was conducted. The Chi-Square/Fischer's exact test (with p ≤ .05 to signify statistical significance) was applied to compare categorical outcomes between Crohn's disease (CD) and ulcerative colitis (UC) patients.

RESULTS

In total, 425 IBD patients (64.9% CD, 53% males) and ≥1 dermatologic diagnosis were included. Presence of ≥1 cutaneous infection was recorded in 42.8% of participants. Acne was the most common non-infectious dermatologic condition (30.8%), followed by eczema (15.8%) and perianal skin tags (14.6%). Angular cheilitis (p = .024), keratosis pilaris (KP, p = .003), and perianal skin complications (i.e., skin tags, fistula, and abscesses; all p < .001) were more frequently diagnosed among children with CD, while fungal skin infections (p = .017) were more frequently diagnosed in UC patients. Severity of IBD correlated with higher prevalence of perianal fistula (p = .003), perianal abscess (p = .041), psoriasis (p < .001), and pyoderma gangrenosum (PG, p = .003).

CONCLUSIONS

Both IBD-specific and IBD-nonspecific dermatologic conditions are very prevalent in childhood IBD, the most common being infectious. Children with CD are more likely to experience angular cheilitis, KP, and perianal skin findings than those with UC. Perianal disease, psoriasis, and PG are associated with more severe IBD.

No Association Between Allergic Diseases and Constipation in Japanese Ulcerative Colitis Patients: A Cross-Sectional Study

BACKGROUND

Constipation is a common gastrointestinal symptom in patients with ulcerative colitis (UC). Several studies on the general population have demonstrated a link between allergic diseases and constipation. However, evidence regarding the association between allergic diseases and constipation in UC is limited. This study aims to evaluate this issue in Japanese patients with UC.

METHODS

This cross-sectional study recruited consecutive 387 patients with UC. We used a self-administered questionnaire to estimate the prevalence of physician-diagnosed allergic diseases. The definition of constipation was based on Rome I criteria and/or medication for constipation.

RESULTS

The prevalence of constipation was 12.5%. The prevalence rates of asthma, atopic dermatitis, pollen allergy, food allergy, and drug allergy were 11.8%, 9.0%, 36.3%, 6.2%, and 8.3%, respectively. Allergic diseases were not associated with constipation (adjusted odds ratio [OR] with asthma (adjusted OR 0.98 [95% confidence interval [CI] 0.27-2.80]), atopic dermatitis (adjusted OR 0.67 [95% CI 0.10-2.56]), pollen allergy (adjusted OR 0.92 [95% CI 0.41-1.97]), food allergy (adjusted OR 0.76 [95% CI 0.11-2.95]), and drug allergy (adjusted OR 1.06 [95% CI 0.28-3.24]). Additionally, the number of allergic diseases was not associated with the prevalence of constipation.

CONCLUSIONS

In Japanese UC patients, no association between allergic diseases and constipation was found.

Poly-omic risk scores predict inflammatory bowel disease diagnosis

Inflammatory bowel disease (IBD) is characterized by complex etiology and a disrupted colonic ecosystem. We provide a framework for the analysis of multi-omic data, which we apply to study the gut ecosystem in IBD. Specifically, we train and validate models using data on the metagenome, metatranscriptome, virome, and metabolome from the Human Microbiome Project 2 IBD multi-omic database, with 1,785 repeated samples from 130 individuals (103 cases and 27 controls). After splitting the participants into training and testing groups, we used mixed-effects least absolute shrinkage and selection operator regression to select features for each omic. These features, with demographic covariates, were used to generate separate single-omic prediction scores. All four single-omic scores were then combined into a final regression to assess the relative importance of the individual omics and the predictive benefits when considered together. We identified several species, pathways, and metabolites known to be associated with IBD risk, and we explored the connections between data sets. Individually, metabolomic and viromic scores were more predictive than metagenomics or metatranscriptomics, and when all four scores were combined, we predicted disease diagnosis with a Nagelkerke's R2 of 0.46 and an area under the curve of 0.80 (95% confidence interval: 0.63, 0.98). Our work supports that some single-omic models for complex traits are more predictive than others, that incorporating multiple omic data sets may improve prediction, and that each omic data type provides a combination of unique and redundant information. This modeling framework can be extended to other complex traits and multi-omic data sets.IMPORTANCEComplex traits are characterized by many biological and environmental factors, such that multi-omic data sets are well-positioned to help us understand their underlying etiologies. We applied a prediction framework across multiple omics (metagenomics, metatranscriptomics, metabolomics, and viromics) from the gut ecosystem to predict inflammatory bowel disease (IBD) diagnosis. The predicted scores from our models highlighted key features and allowed us to compare the relative utility of each omic data set in single-omic versus multi-omic models. Our results emphasized the importance of metabolomics and viromics over metagenomics and metatranscriptomics for predicting IBD status. The greater predictive capability of metabolomics and viromics is likely because these omics serve as markers of lifestyle factors such as diet. This study provides a modeling framework for multi-omic data, and our results show the utility of combining multiple omic data types to disentangle complex disease etiologies and biological signatures.

The re-emerging role of linoleic acid in paediatric asthma

Asthma is the most common chronic disease within the paediatric population. Although it is multifactorial, its onset may be linked to early-life exposures with subsequent impact on immune system development. Microbial and dietary metabolic products have been implicated in the development and exacerbation of paediatric asthma. Linoleic acid is the most common omega-6 polyunsaturated fatty acid in the Western diet. In this review, we summarise the literature regarding the involvement of linoleic acid in the development of and its impact on existing paediatric asthma. First, we summarise the existing knowledge surrounding the relationship between human microbial metabolism and allergic diseases in children. Next, we examine cellular or animal model-based mechanistic studies that investigated the impact of dietary- and microbial-derived linoleic acid metabolites on asthma. Finally, we review the literature investigating the impact of linoleic acid metabolites on the development and exacerbation of childhood asthma. While there is conflicting evidence, there is growing support for a role of linoleic acid in the onset and pathophysiology of asthma. We recommend that additional cellular, animal, and longitudinal studies are performed that target linoleic acid and its metabolites.

Causal relationship between asthma and ulcerative colitis and the mediating role of interleukin-18: a bidirectional Mendelian study and mediation analysis

Objective

Numerous observational investigations have documented a correlation between asthma and ulcerative colitis(UC). In this Mendelian Randomization (MR) study, we utilized extensive summary data from Genome-Wide Association Studies (GWAS) to further estimate the association between adult-onset asthma and the risk of UC, and to investigate the role of Interleukin-18 (IL-18) as a potential mediator.

Materials and methods

A two-step, two-sample MR study was conducted through mediation analysis. For this study, we employed a two-sample MR analysis using the inverse variance-weighted (IVW), weighted median, weighted mode, and MR-Egger regression techniques. We utilized publicly accessible summary statistics from a GWAS meta-analysis of adult-onset asthma in the UK Biobank (n=327,253; cases=26,582; controls=300,671) as the exposure factor. The outcomes were derived from GWAS data of individuals with European ancestry (n=26,405; cases=6,687; controls=19,718). GWAS data for IL-18 were obtained from individuals of European ancestry (n=9,785,222; cases=3,636; controls=9,781,586).

Results

The MR analysis indicates that adult-onset asthma is associated with an increased risk of UC, with an odds ratio (OR) of 1.019 (95% CI 1.001-1.045, P=0.006). However, there is no strong evidence to suggest that UC significantly impacts the risk of adult-onset asthma. IL-18 may act as a potential mediator in the causal relationship between adult-onset asthma and UC, with a mediation proportion of 3.9% (95% CI, 0.6%-6.9%).

Conclusion

In summary, our study established a causal relationship between asthma and UC, in which IL-18 contributes to a small extent. However, the primary factors underlying the influence of asthma on UC remain unclear. Future research should focus on identifying other potential mediators. In clinical practice, it is important to pay greater attention to intestinal lesions in patients with asthma.

Medication-Wide Study: Exploring Medication Use 10 Years Before a Diagnosis of Inflammatory Bowel Disease

INTRODUCTION

There is growing interest in the prediagnostic phase of inflammatory bowel disease (IBD) and in the overlap of IBD with other diseases. We described and compared use of any prescription medication between individuals with and without IBD in a 10-year period preceding diagnosis.

METHODS

Based on cross-linked nationwide registers, we identified 29,219 individuals diagnosed with IBD in Denmark between 2005 and 2018 and matched to 292,190 IBD-free individuals. The primary outcome was use of any prescription medication in years 1-10 before IBD diagnosis/matching date. Participants were considered as medication users if they redeemed ≥1 prescription for any medication in the World Health Organization Anatomical Therapeutic Chemical (ATC) main groups or subgroups before diagnosis/matching.

RESULTS

The IBD population had a universally increased use of medications compared with the matched population before IBD diagnosis. At 10 years before diagnosis, the proportion of users was 1.1-fold to 1.8-fold higher in the IBD population in 12 of 14 ATC main groups of medication ( P -value < 0.0001). This applied across age, sex, and IBD subtypes, although it was the most pronounced for Crohn's disease (CD). Two years before diagnosis, the IBD population had a steep increase in medication use for several organ systems. When analyzing therapeutic subgroups of medication, the CD population exhibited 2.7, 2.3, 1.9, and 1.9 times more users of immunosuppressants, antianemic preparations, analgesics, and psycholeptics, respectively, than the matched population 10 years before diagnosis ( P -value < 0.0001).

DISCUSSION

Our findings demonstrate universally increased medication use years before IBD, especially CD, diagnosis and indicates multiorgan involvement in IBD.

Lung Involvement in Inflammatory Bowel Diseases: Shared Pathways and Unwanted Connections

Inflammatory bowel diseases (IBDs) are chronic, relapsing inflammatory disorders of the gastrointestinal tract, frequently associated with extraintestinal manifestations (EIMs) that can severely affect IBD patients' quality of life, sometimes even becoming life-threatening. Respiratory diseases have always been considered a rare and subsequently neglected extraintestinal manifestations of IBD. However, increasing evidence has demonstrated that respiratory involvement is frequent in IBD patients, even in the absence of respiratory symptoms. Airway inflammation is the most common milieu of IBD-related involvement, with bronchiectasis being the most common manifestation. Furthermore, significant differences in prevalence and types of involvement are present between Crohn's disease and ulcerative colitis. The same embryological origin of respiratory and gastrointestinal tissue, in addition to exposure to common antigens and cytokine networks, may all play a potential role in the respiratory involvement. Furthermore, other causes such as drug-related toxicity and infections must always be considered. This article aims at reviewing the current evidence on the association between IBD and respiratory diseases. The purpose is to raise awareness of respiratory manifestation among IBD specialists and emphasize the need for identifying respiratory diseases in early stages to promptly treat these conditions, avoid worsening morbidity, and prevent lung damage.

De novo identification of complex traits associated with asthma

Introduction

Asthma is a heterogeneous inflammatory disease often associated with other complex phenotypes. Identifying asthma-associated diseases and uncovering the molecular mechanisms mediating their interaction can help detangle the heterogeneity of asthma. Network analysis is a powerful approach for untangling such inter-disease relationships.

Methods

Here, we integrated information on physical contacts between common single nucleotide polymorphisms (SNPs) and gene expression with expression quantitative trait loci (eQTL) data from the lung and whole blood to construct two tissue-specific spatial gene regulatory networks (GRN). We then located the asthma GRN (level 0) within each tissue-specific GRN by identifying the genes that are functionally affected by asthma-associated spatial eQTLs. Curated protein interaction partners were subsequently identified up to four edges or levels away from the asthma GRN. The eQTLs spatially regulating genes on levels 0-4 were queried against the GWAS Catalog to identify the traits enriched (hypergeometric test; FDR ≤ 0.05) in each level.

Results

We identified 80 and 82 traits significantly enriched in the lung and blood GRNs, respectively. All identified traits were previously reported to be comorbid or associated (positively or negatively) with asthma (e.g., depressive symptoms and lung cancer), except 8 traits whose association with asthma is yet to be confirmed (e.g., reticulocyte count). Our analysis additionally pinpoints the variants and genes that link asthma to the identified asthma-associated traits, a subset of which was replicated in a comorbidity analysis using health records of 26,781 asthma patients in New Zealand.

Discussion

Our discovery approach identifies enriched traits in the regulatory space proximal to asthma, in the tissue of interest, without a priori selection of the interacting traits. The predictions it makes expand our understanding of possible shared molecular interactions and therapeutic targets for asthma, where no cure is currently available.

Atopic dermatitis is associated with the clinical course of inflammatory bowel disease

OBJECTIVES

There are a few studies about the relationship between inflammatory bowel disease (IBD) and atopic dermatitis (AD). It is implied that both diseases have common pathophysiologic mechanisms and can affect each other. However, little information is available on the effect of AD on the clinical course of patients with IBD.

METHODS

This is a multi-center, retrospective, observational study. We define AD as a chronic eczematoid dermatosis diagnosed by dermatologists. Patients with concurrent IBD and AD were defined as a case group. Age, gender, and IBD subtype-matched patients without AD were included as a reference group.

RESULTS

The numbers of patients in the case and reference groups were 61 and 122 respectively. There was a significantly shorter biologics-free survival in the case group than that in the reference group according to the multivariable-adjusted Cox regression analysis with the onset age, disease duration, smoking status, use of steroid, use of immunomodulator, initial C-reactive protein, initial erythrocyte sedimentation rate, presence of other allergic diseases and initial disease severity [hazard ratio (HR) 1.828, 95% confidence interval (CI) 1.022-3.271, p = .042]. The trend was consistent in the subgroup analysis with ulcerative colitis (HR 3.498, 95% CI 1.066-11.481, p = .039), but not with Crohn's disease (HR 1.542, 95% CI 0.720-3.301, p = .265).

CONCLUSIONS

AD showed a significant effect on the biologics-free survival of patients with IBD and especially the UC subtype. Further mechanistic research is required to elucidate the pathogenesis of AD on the clinical course of IBD.

Inflammatory bowel disease and asthma. Results from the RHINE study

BACKGROUND

Asthma and inflammatory bowel disease (IBD) are common inflammatory diseases. The aim of this study was to investigate the associations of IBD with asthma and respiratory symptoms.

METHODS

This study is based on 13,499 participants from seven northern European countries that filled in a postal questionnaire on asthma, respiratory symptoms, IBD including ulcerative colitis and Crohn's disease and various lifestyle variables.

RESULTS

There were 195 participants with IBD. The prevalence of asthma (14.5 vs 8.1%, p = 0.001), different respiratory symptoms (range 11.9-36.8% vs range 6.0-18.6%, p < 0.005), non-infectious rhinitis (52.1 vs. 41.6%, p = 0.004) and chronic rhinosinusitis (11.6 vs 6.0%, p = 0.001) were higher in subjects with IBD than in those without IBD. In multivariable regression analysis, the association between IBD and asthma was statistically significant (OR 1.95 (95% CI 1.28-2.96)) after adjusting for confounders such as sex, BMI, smoking history, educational level and physical activity. There was a significant association between asthma and ulcerative colitis (adjusted OR 2.02 (95% CI 1.27-2.19)), and asthma but not Crohn's disease (adjusted OR 1.66 (95% CI 0.69-3.95)). A significant gender interaction was found with a significant association between IBD and asthma in women but not in men ((OR 2.72 (95% CI 1.67-4.46) vs OR 0.87 (95% CI 0.35-2.19), p = 0.038).

CONCLUSIONS

Patients with IBD, particularly those with ulcerative colitis and female, have a higher prevalence of asthma and respiratory symptoms. Our findings indicate that it is important to consider respiratory symptoms and disorders when examining patients with manifest or suspected IBD.

Influence of diabetes mellitus on inflammatory bowel disease course and treatment outcomes. A systematic review with meta-analysis

BACKGROUND

Diabetes Mellitus (DM) may occur in IBD and influence the disease progression.

AIM

To compare disease course and treatment outcomes in IBD patients with and without DM.

METHODS

This is a systematic review with meta-analysis comparing patients with IBD plus DM with patients with IBD only.

PRIMARY ENDPOINTS

need for surgery, IBD-related complications, hospitalizations, sepsis, mortality. Quality of life and costs were assessed.

RESULTS

Five studies with 71,216 patients (49.1% with DM) were included. Risk for IBD-related complications (OR=1.12, I2 98% p = 0.77), mortality (OR=1.52, I2 98% p = 0.37) and IBD-related surgery (OR=1.20, I2 81% p = 0.26) did not differ. Risk of IBD-related hospitalizations (OR=2.52, I2 0% p < 0.00001) and sepsis (OR=1.56, I2 88% p = 0.0003) was higher in the IBD+DM group. Risk of pneumonia and urinary tract infections was higher in the IBD+DM group (OR=1.72 and OR=1.93), while risk of C. Difficile infection did not differ (OR=1.22 I2 88% p = 0.37). Mean Short Inflammatory Bowel Disease Questionnaire score was lower in the IBD+DM group (38.9 vs. 47, p = 0.03). Mean health care costs per year were $10,598.2 vs $3747.3 (p < 0.001).

CONCLUSION

DM might negatively affect the course of IBD by increasing the risk of hospitalization and infections, but not IBD-related complications and mortality.

Association of rheumatoid arthritis with bronchial asthma and asthma-related comorbidities: A population-based national surveillance study

Background

The aim of this study was to investigate the impact of rheumatoid arthritis (RA) on the prevalence of bronchial asthma and asthma-related comorbidities. We also aimed to identify the influence of RA on interrelationship between asthma and asthma-related comorbidities.

Methods

From the Korean National Health and Nutrition Examination Survey, participants &gt;40 years of age who completed questionnaires and spirometry tests were enrolled. Patient data on RA, asthma, allergic rhinitis, atopic dermatitis, chronic obstructive pulmonary disease (COPD), sinusitis, otitis media, and body mass index (BMI) were collected. Logistic regression and network analyses were performed.

Results

A total of 14,272 subjects were enrolled, among which, 334 (2.4%) had RA. RA was significantly associated with asthma (OR 2.32; 95% CI 1.51–3.57), allergic rhinitis (OR 1.51; 95% CI 1.08–2.10), and sinusitis (OR 1.64; 95% CI 1.08–2.50). The network analysis of total patients revealed a positive interrelationship between asthma and allergic rhinitis, sinusitis, otitis media, atopic dermatitis, BMI, and RA. The interrelationship between asthma and sinusitis was stronger in the RA group. Of note, the relationship between asthma and BMI was distinctively found only in the RA group (r = 0.214, P &lt; 0.05). In patients with asthma, the prevalence of obesity was 64% in the presence of RA, and 40% in the absence of RA (P = 0.034).

Conclusion

This study supports the positive association of RA with asthma, allergic rhinitis, and sinusitis. Our analysis suggests a notable interrelationship between the presence of asthma and higher BMI values in patients with RA, indicating that asthma is more obesity-related in patients with RA.

Gastrointestinal consequences of lipopolysaccharide-induced lung inflammation

BACKGROUND

Respiratory inflammation is the body's response to lung infection, trauma or hypersensitivity and is often accompanied by comorbidities, including gastrointestinal (GI) symptoms. Why respiratory inflammation is accompanied by GI dysfunction remains unclear. Here, we investigate the effect of lipopolysaccharide (LPS)-induced lung inflammation on intestinal barrier integrity, tight-junctions, enteric neurons and inflammatory marker expression.

METHODS

Female C57bl/6 mice (6-8 weeks) were intratracheally administered LPS (5 µg) or sterile saline, and assessed after either 24 or 72 h. Total and differential cell counts in bronchoalveolar lavage fluid (BALF) were used to evaluate lung inflammation. Intestinal barrier integrity was assessed via cross sectional immunohistochemistry of tight junction markers claudin-1, claudin-4 and EpCAM. Changes in the enteric nervous system (ENS) and inflammation in the intestine were quantified immunohistochemically using neuronal markers Hu + and nNOS, glial markers GFAP and S100β and pan leukocyte marker CD45.

RESULTS

Intratracheal LPS significantly increased the number of neutrophils in BALF at 24 and 72 h. These changes were associated with an increase in CD45 + cells in the ileal mucosa at 24 and 72 h, increased goblet cell expression at 24 h, and increased expression of EpCAM at 72 h. LPS had no effect on the expression of GFAP, S100β, nor the number of Hu + neurons or proportion of nNOS neurons in the myenteric plexus.

CONCLUSIONS

Intratracheal LPS administration induces inflammation in the ileum that is associated with enhanced expression of EpCAM, decreased claudin-4 expression and increased goblet cell density, these changes may contribute to systemic inflammation that is known to accompany many inflammatory diseases of the lung.

Dachengqi Decoction alleviates intestinal inflammation in ovalbumin-induced asthma by reducing group 2 innate lymphoid cells in a microbiota-dependent manner

Background and aim

Dachengqi Decoction (DCQD) as a classic traditional Chinese medicine has been reported to be effective in treating asthma, but its mechanism remains unknown. This study aimed to reveal the mechanisms of DCQD on the intestinal complications of asthma mediated by group 2 innate lymphoid cells (ILC2) and intestinal microbiota.

Experimental procedure

Ovalbumin (OVA) was used to construct asthmatic murine models. IgE, cytokines (e.g., IL-4, IL-5), fecal water content, colonic length, histopathologic appearance, and gut microbiota were evaluated in asthmatic mice treated with DCQD. Finally, we administered DCQD to antibiotic-treated asthmatic mice to measure the ILC2 in the small intestine and colon.

Results and conclusion

DCQD decreased pulmonary IgE, IL-4, and IL-5 levels in asthmatic mice. The fecal water content, the colonic length weight loss, and the epithelial damage of jejunum, ileum, and colon of asthmatic mice were ameliorated by DCQD. Meanwhile, DCQD greatly improved intestinal dysbiosis by enriching Allobaculum, Romboutsia and Turicibacter in the whole intestine, and Lactobacillus gasseri only in the colon. However, DCQD caused less abundant Faecalibaculum and Lactobacillus vaginalis in the small intestine of asthmatic mice. A higher ILC2 proportion in different gut segments of asthmatic mice was reversed by DCQD. Finally, significant correlations appeared between DCQD-mediated specific bacteria and cytokines (e.g., IL-4, IL-5) or ILC2. These findings indicate that DCQD alleviated the concurrent intestinal inflammation in OVA-induced asthma by decreasing the excessive accumulation of intestinal ILC2 in a microbiota-dependent manner across different gut locations.

Geosocial Features and Loss of Biodiversity Underlie Variable Rates of Inflammatory Bowel Disease in a Large Developing Country: A Population-Based Study

BACKGROUND

The epidemiology of inflammatory bowel disease (IBD) in developing countries may uncover etiopathogenic factors. We investigated IBD prevalence in Brazil by investigating its geographic, spatial, and temporal distribution, and attempted to identify factors associated with its recent increase.

METHODS

A drug prescription database was queried longitudinally to identify patients and verify population distribution and density, race, urbanicity, sanitation, and Human Development Index. Prevalence was calculated using the number of IBD patients and the population estimated during the same decade. Data were matched to indices using linear regression analyses.

RESULTS

We identified 162 894 IBD patients, 59% with ulcerative colitis (UC) and 41% with Crohn's disease (CD). The overall prevalence of IBD was 80 per 100 000, with 46 per 100 000 for UC and 36 per 100 000 for CD. Estimated rates adjusted to total population showed that IBD more than triplicated from 2008 to 2017. The distribution of IBD demonstrated a South-to-North gradient that generally followed population apportionment. However, marked regional differences and disease clusters were identified that did not fit with conventionally accepted IBD epidemiological associations, revealing that the rise of IBD was variable. In some areas, loss of biodiversity was associated with high IBD prevalence.

CONCLUSIONS

When distribution is considered in the context of IBD prevalence, marked regional differences become evident. Despite a background of Westernization, hotspots of IBD are recognized that are not explained by population density, urbanicity, sanitation, or other indices but apparently are explained by biodiversity loss. Thus, the rise of IBD in developing countries is not uniform, but rather is one that varies depending on yet unexplored factors like geoecological conditions.

Paediatric asthma and non-allergic comorbidities: A review of current risk and proposed mechanisms

It is increasingly recognized that children with asthma are at a higher risk of other non-allergic concurrent diseases than the non-asthma population. A plethora of recent research has reported on these comorbidities and progress has been made in understanding the mechanisms for comorbidity. The goal of this review was to assess the most recent evidence (2016-2021) on the extent of common comorbidities (obesity, depression and anxiety, neurodevelopmental disorders, sleep disorders and autoimmune diseases) and the latest mechanistic research, highlighting knowledge gaps requiring further investigation. We found that the majority of recent studies from around the world demonstrate that children with asthma are at an increased risk of having at least one of the studied comorbidities. A range of potential mechanisms were identified including common early life risk factors, common genetic factors, causal relationships, asthma medication and embryologic origins. Studies varied in their selection of population, asthma definition and outcome definitions. Next, steps in future studies should include using objective measures of asthma, such as lung function and immunological data, as well as investigating asthma phenotypes and endotypes. Larger complex genetic analyses are needed, including genome-wide association studies, gene expression-functional as well as pathway analyses or Mendelian randomization techniques; and identification of gene-environment interactions, such as epi-genetic studies or twin analyses, including omics and early life exposure data. Importantly, research should have relevance to clinical and public health translation including clinical practice, asthma management guidelines and intervention studies aimed at reducing comorbidities.

Aeroallergen-related Diseases Predate the Diagnosis of Inflammatory Bowel Disease

OBJECTIVE

This study aimed to determine whether having a diagnosis of asthma or allergic rhinitis (AR) increased the risk of being diagnosed with inflammatory bowel disease (IBD) and whether there was increased incidence of these diseases after a diagnosis of IBD.

DESIGN

This is a retrospective, historical cohort-based study. We used the administrative data of Manitoba Health and the population-based University of Manitoba IBD Epidemiology Database. We used numbers of prescriptions for drugs used to treat asthma and to treat AR to identify diagnoses of asthma and AR, respectively.We calculated relative risks (RRs) to assess incidence of IBD compared with matched controls after diagnoses of asthma and AR and hazard ratios to determine the incidence of asthma and AR after IBD diagnosis.

RESULTS

Compared with controls, a diagnosis of asthma or AR preceding a diagnosis of IBD was increased in cases (RR, 1.62; 95% confidence interval [CI], 1.50-1.75; and RR, 2.10; 95% CI, 1.97-2.24) with a similar outcome by subtype of IBD (Crohn's disease vs ulcerative colitis) and by sex. On sensitivity analysis, diagnoses of asthma or AR were comparable when considering at least 5, 10, 15 or 20 drug prescriptions. Persons with IBD were more likely to develop asthma or AR than controls after being diagnosed with IBD (hazard ratio for asthma, 1.31, 95% CI, 1.18-1.45; and hazard ratio for AR, 2.62, 95% CI, 2.45-2.80).

CONCLUSIONS

The association between asthma, AR, and IBD suggest the possibility that whatever triggers the onset of these atopic diseases may trigger the onset of IBD as well, and aeroallergens are plausible culprits.

Probiotics: Protecting Our Health from the Gut

The gut microbiota (GM) comprises billions of microorganisms in the human gastrointestinal tract. This microbial community exerts numerous physiological functions. Prominent among these functions is the effect on host immunity through the uptake of nutrients that strengthen intestinal cells and cells involved in the immune response. The physiological functions of the GM are not limited to the gut, but bidirectional interactions between the gut microbiota and various extraintestinal organs have been identified. These interactions have been termed interorganic axes by several authors, among which the gut-brain, gut-skin, gut-lung, gut-heart, and gut-metabolism axes stand out. It has been shown that an organism is healthy or in homeostasis when the GM is in balance. However, altered GM or dysbiosis represents a critical factor in the pathogenesis of many local and systemic diseases. Therefore, probiotics intervene in this context, which, according to various published studies, allows balance to be maintained in the GM, leading to an individual's good health.

Airway involvement in inflammatory bowel disease: Inflammatory bowel disease patients have bronchial wall thickening

BACKGROUND

Recent epidemiological studies have revealed a high co-occurrence of asthma or COPD and IBD. Herein, we examined the impact of IBD on the bronchial wall structure using three-dimensional computed tomography (3D-CT).

METHODS

Subjects who were diagnosed with IBD and had undergone chest CT were recruited from consecutive medical records. Screening chest CT scan data during the same period were used as normal controls. Airway dimensions were measured by validated software.

RESULTS

Overall, 136 IBD and 99 control subjects were recruited. The bronchial walls of patients with IBD were significantly thicker than those of control subjects. Multiple linear regression analysis showed that Crohn's disease and ulcerative colitis were independent determinants of wall area percentage after adjusting for age, sex, and smoking status.

CONCLUSIONS

Airway walls in patients with IBD were thicker than those in normal control subjects. Airway involvement in IBD may be more frequent than recognized.

Bypassing the Gut-Lung Axis via Microbial Metabolites: Implications for Chronic Respiratory Diseases

The gut microbiome engages in constant interactions with the immune system, laying down the fundamentals of what we perceive as health or disease. The gut microbiota acts locally in the intestines and distally in other organs, such as the lungs. This influence (termed “the gut–lung axis”) constitutes the basis for harnessing the microbiome to prevent or treat chronic respiratory diseases. Within this context, two approaches gained the most attention: the diet interventions (which shape the microbiome) and the probiotics (which exert beneficial effects directly on the host). Microbial products, which constitute a means of communication along the gut–lung axis, are only now emerging as a new class of potential therapeutics. Here, we provide a comprehensive overview of microbial products active in the airways, describe the immunological mechanisms they trigger, and discuss their clinical advantages and pitfalls.

A systematic review and functional bioinformatics analysis of genes associated with Crohn's disease identify more than 120 related genes

BACKGROUND

Crohn's disease is one of the two categories of inflammatory bowel diseases that affect the gastrointestinal tract. The heritability estimate has been reported to be 0.75. Several genes linked to Crohn's disease risk have been identified using a plethora of strategies such as linkage-based studies, candidate gene association studies, and lately through genome-wide association studies (GWAS). Nevertheless, to our knowledge, a compendium of all the genes that have been associated with CD is lacking.

METHODS

We conducted functional analyses of a gene set generated from a systematic review where genes potentially related to CD found in the literature were analyzed and classified depending on the genetic evidence reported and putative biological function. For this, we retrieved and analyzed 2496 abstracts comprising 1067 human genes plus 22 publications regarding 133 genes from GWAS Catalog. Then, each gene was curated and categorized according to the type of evidence associated with Crohn's disease.

RESULTS

We identified 126 genes associated with Crohn's disease risk by specific experiments. Additionally, 71 genes were recognized associated through GWAS alone, 18 to treatment response, 41 to disease complications, and 81 to related diseases. Bioinformatic analysis of the 126 genes supports their importance in Crohn's disease and highlights genes associated with specific aspects such as symptoms, drugs, and comorbidities. Importantly, most genes were not included in commercial genetic panels suggesting that Crohn's disease is genetically underdiagnosed.

CONCLUSIONS

We identified a total of 126 genes from PubMed and 71 from GWAS that showed evidence of association to diagnosis, 18 to treatment response, and 41 to disease complications in Crohn's disease. This prioritized gene catalog can be explored at http://victortrevino.bioinformatics.mx/CrohnDisease .

Modification of the chemically induced inflammation assay reveals the Janus face of a phenol rich fulvic acid

Inflammation is an essential process as a reaction towards infections or wounding. Exposure to hazardous environmental pollutants can lead to chronic inflammations, where the resolving phase is delayed or blocked. Very contradictory studies have been reported on the pro- and anti-inflammatory effects of humic substances (HSs) leading to significant disagreements between researchers. To a certain extent, this can be attributed to the chemical heterogeneity of this group of xenobiotics. Here we show for the first time that pro- and anti-inflammatory effects can occur by one HSs. We adapted an assay that uses green fluorescence-labeled zebrafish larvae and CuSO₄ to indue an inflammation. In wild-type larvae, exposure to 50 µM CuSO₄ for 2 h activated the production of reactive oxygen species, which can be monitored with a fluorescence dye (H2DCFDA) and a microplate reader. This allows not only the use of wild-type fish but also a temporal separation of copper exposure and inflammatory substance while retaining the high throughput. This modified assay was then used to evaluate the inflammatory properties of a fulvic acid (FA). We found, that the aromatic structure of the FA protects from inflammation at 5 and 50 mg C/L, while the persistent free radicals enhance the copper-induced inflammation at ≥ 300 mg C/L.

Dysbiosis in Inflammatory Bowel Disease: Pathogenic Role and Potential Therapeutic Targets

Microbe-host communication is essential to maintain vital functions of a healthy host, and its disruption has been associated with several diseases, including Crohn's disease and ulcerative colitis, the two major forms of inflammatory bowel disease (IBD). Although individual members of the intestinal microbiota have been associated with experimental IBD, identifying microorganisms that affect disease susceptibility and phenotypes in humans remains a considerable challenge. Currently, the lack of a definition between what is healthy and what is a dysbiotic gut microbiome limits research. Nevertheless, although clear proof-of-concept of causality is still lacking, there is an increasingly evident need to understand the microbial basis of IBD at the microbial strain, genomic, epigenomic, and functional levels and in specific clinical contexts. Recent information on the role of diet and novel environmental risk factors affecting the gut microbiome has direct implications for the immune response that impacts the development of IBD. The complexity of IBD pathogenesis, involving multiple distinct elements, suggests the need for an integrative approach, likely utilizing computational modeling of molecular datasets to identify more specific therapeutic targets.

Asthma and the risk of gastrointestinal disorders: a Mendelian randomization study

BACKGROUND

The question of whether asthma is causally related to gastrointestinal disorders remained unanswered so far. Thus, this study investigated whether there is such a relation and whether the time of onset of asthma plays a role in the occurrence of the following gastrointestinal disorders: peptic ulcer disease (PUD), gastroesophageal reflux disease (GORD), irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD) including the distinction between Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

Using summary data of genome-wide association studies (GWASs), we ran Mendelian randomization analyses based on up to 456,327 European participants. Outlier assessment, a series of sensitivity analyses and validation of IBD results in a second GWAS were performed to confirm the results.

RESULTS

Presented ORs represent the average change in the outcome per 2.72-fold increase in the prevalence of the exposure. Genetically predicted childhood-onset asthma was positively associated with PUD, GORD, and IBS with similar odds ratios near 1.003 and adjusted P-values from 0.007 (GORD) to 0.047 (PUD). Furthermore, it was inversely related to IBD (OR = 0.992, 95% CI: 0.986, 0.998, adjusted P = 0.023) and suggestively associated with its UC subtype (OR = 0.990, 95% CI: 0.982, 0.998, adjusted P = 0.059). There were no associations between genetically predicted adult-onset asthma and the mentioned gastrointestinal disorders.

CONCLUSIONS

This study provides evidence that the presence of asthma onset in childhood increases the risk for GORD, PUD, and IBS but decreases the risk for IBD in adults. The lower risk for IBD may be attributed to a lower risk primarily for UC.

Modeling approaches for probing cross-feeding interactions in the human gut microbiome

Microbial communities perform emergent activities that are essentially different from those carried by their individual members. The gut microbiome and its metabolites have a significant impact on the host, contributing to homeostasis or disease. Food molecules shape this community, being fermented through cross-feeding interactions of metabolites such as lactate, acetate, and amino acids, or products derived from macromolecule degradation. Mathematical and experimental approaches have been applied to understand and predict the interactions between microorganisms in complex communities such as the gut microbiota. Rational and mechanistic understanding of microbial interactions is essential to exploit their metabolic activities and identify keystone taxa and metabolites. The latter could be used in turn to modulate or replicate the metabolic behavior of the community in different contexts. This review aims to highlight recent experimental and modeling approaches for studying cross-feeding interactions within the gut microbiome. We focus on short-chain fatty acid production and fiber fermentation, which are fundamental processes in human health and disease. Special attention is paid to modeling approaches, particularly kinetic and genome-scale stoichiometric models of metabolism, to integrate experimental data under different diet and health conditions. Finally, we discuss limitations and challenges for the broad application of these modeling approaches and their experimental verification for improving our understanding of the mechanisms of microbial interactions.

Allergic manifestations in autoimmune gastrointestinal disorders

Allergic disorders target a young population, are increasing in both incidence and prevalence and are associated with significant disease burden. They result from the complex interplay between (epi)genetic and environmental factors, resulting in a Th2 inflammatory process targeting the epithelium of the respiratory tract (allergic rhinitis and asthma), skin (atopic dermatitis), and gastrointestinal tract (food allergy). Although the exact pathogenic mechanisms remain elusive, an altered immune system response in the gut is increasingly recognized as a relevant step. Allergic and gastrointestinal autoimmune disorders share several epidemiological, pathogenic and risk factors and several treatment modalities. Here we revise the current literature and show that allergic disorders are highly prevalent in gastrointestinal autoimmune diseases, including celiac disease, inflammatory bowel disease, autoimmune pancreatitis, and autoimmune cholangiopathies. No data are available for some autoimmune diseases, such as autoimmune gastritis and autoimmune enteropathy. To ensure the comprehensive care of patients with autoimmune gastrointestinal disorders, along with disease-specific factors, the presence of allergic disorders should be evaluated and treated when present, possibly targeting shared molecular pathways. Future studies are needed to define the exact pathogenic mechanisms underpinning the association between allergic and autoimmune diseases of the gastrointestinal tract.

Microbial-derived indoles inhibit neutrophil myeloperoxidase to diminish bystander tissue damage

During episodes of acute inflammation, polymorphonuclear leukocytes (PMNs) are actively recruited to sites of inflammation or injury where they provide anti-microbial and wound-healing functions. One enzyme crucial for fulfilling these functions is myeloperoxidase (MPO), which generates hypochlorous acid from Cl^- and hydrogen peroxide. The potential exists, however, that uncontrolled the extracellular generation of hypochlorous acid by MPO can cause bystander tissue damage and inhibit the healing response. Previous work suggests that the microbiota-derived tryptophan metabolites 1H-indole and related molecules ("indoles") are protective during intestinal inflammation, although their precise mechanism of action is unclear. In the present work, we serendipitously discovered that indoles are potent and selective inhibitors of MPO. Using both primary human PMNs and recombinant human MPO in a cell-free system, we revealed that indoles inhibit MPO at physiologic concentrations. Particularly, indoles block the chlorinating activity of MPO, a reliable marker for MPO-associated tissue damage, as measured by coulometric-coupled HPLC. Further, we observed direct interaction between indoles and MPO using the established biochemical techniques microscale thermophoresis and STD-NMR. Utilizing a murine colitis model, we demonstrate that indoles inhibit bystander tissue damage, reflected in decreased colon 3-chlorotyrosine and pro-inflammatory chemokine expression in vivo. Taken together, these results identify microbiota-derived indoles that acts as endogenous immunomodulatory compounds through their actions on MPO, suggesting a symbiotic association between the gut microbiota and host innate immune system. Such findings offer exciting new targets for future pharmacological intervention.

Identification of Risk Factors for Coexisting Sinusitis and Inflammatory Bowel Disease

Background

This study aimed to analyze the association of coexisting sinusitis and inflammatory bowel disease (IBD), establish significant factors involved in their development, and enable further biological correlation between these 2 diseases.

Methods

The IBD and Sinusitis Study at UChicago Medicine (TISSUe) is a retrospective, single-center study. We reviewed patients to confirm IBD and chronic sinusitis diagnoses. Case-control propensity score matching was performed using matched controls with IBD only or sinusitis only. Statistical methods included chi-squared test and Wilcoxon rank sum test. Logistic regression analysis was performed, and factors were considered significant if P &lt; .05.

Results

Stratifying 214 patients with coexisting IBD and sinusitis, 176 patients had IBD first and 38 patients had sinusitis first. Multivariable analysis of factors associated with subsequent disease with matched controls determined that duration of disease, UC, steroid exposure ever, and younger age of IBD diagnosis were associated with subsequent sinusitis in patients with IBD; steroid exposure ever and duration of sinusitis were significantly associated with subsequent IBD in patients with sinusitis.

Conclusion

This study suggests that IBD maintenance therapies are not associated with increased risk of sinusitis, as proposed by adverse events in clinical trial data; rather, UC diagnosis and duration of disease may be more influential in sinusitis development. While further studies are necessary, this study also demonstrates that sinusitis precedes IBD in some patients, probing its biological association with IBD and possible classification as an extraintestinal manifestation.

Immune-mediated diseases and risk of Crohn's disease or ulcerative colitis: a prospective cohort study

BACKGROUND

Although immune-mediated diseases (IMDs) including inflammatory bowel diseases (IBDs) are known to cluster, to what extent this is due to common environmental influences is unknown.

AIM

To examine the incidence of IBD in individuals with another IMD.

METHODS

We used data from the prospective Nurses' Health Study II cohort (1995-2017) to examine the effect of diagnoses of several common IMDs on subsequent risk of Crohn's disease (CD) or ulcerative colitis (UC) using Cox proportional hazards models, adjusting for detailed diet and lifestyle confounders.

RESULTS

We documented 132 cases of CD and 186 cases of UC over 2 016 163 person-years of follow-up (median age at IBD diagnosis 50 years). Compared to participants with no history of IMD, the HRs of CD for those with 1 and ≥ 2 IMDs were 2.57 (95% CI 1.77-3.74) and 2.74 (95% CI 1.36 to 5.49), respectively (P_trend  < 0.0001). This association was only modestly attenuated by adjustment for environmental risk factors (HR 2.35 and 2.46, respectively). The risk of UC was not increased, with multivariable-adjusted HRs of 1.22 (95% CI 0.85-1.76) and 1.33 (95% CI 0.67-2.65) for those with 1 and ≥ 2 IMDs, respectively, compared to those with none (P_trend 0.16) (P_{heterogeneity} comparing CD and UC 0.037). Asthma, atopic dermatitis, psoriasis and rosacea were individually associated with higher risk of CD (HR ranging from 2.15 to 3.39) but not UC.

CONCLUSIONS

Individuals with one or more IMDs are at an increased risk for CD but not UC.

Alteration of Lung and Gut Microbiota in IL-13-Transgenic Mice Simulating Chronic Asthma

Increasing evidence suggests a potential role of microbial colonization in the inception of chronic airway diseases. However, it is not clear whether the lung and gut microbiome dysbiosis is coincidental or a result of mutual interaction. In this study, we investigated the airway microbiome in interleukin 13 (IL-13)-rich lung environment and related alterations of the gut microbiome. IL-13- overexpressing transgenic (TG) mice presented enhanced eosinophilic inflammatory responses and mucus production, together with airway hyperresponsiveness and subepithelial fibrosis. While bronchoalveolar lavage fluid and cecum samples obtained from 10-week-old IL-13 TG mice and their C57BL/6 wild-type (WT) littermates showed no significant differences in alpha diversity of lung and gut microbiome, they presented altered beta diversity in both lung and gut microbiota in the IL-13 TG mice compared to the WT mice. Lung-specific IL-13 overexpression also altered the composition of the gut as well as the lung microbiome. In particular, IL-13 TG mice showed an increased proportion of Proteobacteria and Cyanobacteria and a decreased amount of Bacteroidetes in the lungs, and depletion of Firmicutes and Proteobacteria in the gut. The patterns of polymicrobial interaction within the lung microbiota were different between WT and IL-13 TG mice. For instance, in IL-13 TG mice, lung Mesorhizobium significantly affected the alpha diversity of both lung and gut microbiomes. In summary, chronic asthma-like pathologic changes can alter the lung microbiota and affect the gut microbiome. These findings suggest that the lung-gut microbial axis might actually work in asthma.

Identification and Evaluation of Controlled Trials in Pediatric Cardiology: Crowdsourced Scoping Review and Creation of Accessible Searchable Database

Cardiac disease in children is associated with significant morbidity and mortality as well as increased health resource utilisation. There is a perception that there is a paucity of high-quality studies, particularly randomized controlled trials (RCTs), in the field of pediatric cardiology. We sought to identify, examine, and map the range of RCTs conducted in children with cardiac conditions, including the development of a searchable open-access database. A literature search was conducted encompassing MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials from inception to 2018. All English-language RCTs enrolling children (age 0-21 years) with cardiac conditions were included. Data extraction and risk of bias assessments were performed in duplicate via crowdsourcing for each eligible study and entered into an online database. A total of 933 RCTs met eligibility criteria. Median trial recruitment was 49 patients (interquartile range 30-86) with 18.9% of studies (n = 176) including > 100 patients. A wide variety of populations and interventions were encompassed with congenital heart disease (79.8% of RCTs) and medications (63.3% of RCTs) often studied. Just over one-half of the trials (53.4%) clearly identified a primary outcome, and fewer than half (46.6%) fully documented a robust randomization process. Trials were summarised in a searchable online database (https://pediatrics.knack.com/cardiology-rct-database#cardiology-rcts/). Contrary to a commonly held perception, there are nearly 1,000 published RCTs in pediatric cardiology. The open-access database created as part of this project provides a resource that facilitates an efficient comprehensive review of the literature for clinicians and researchers caring for children with cardiac issues.

Patients with asthma have a higher risk of rheumatoid arthritis: A systematic review and meta-analysis

OBJECTIVE

This study aimed to investigate whether patients with asthma have a higher risk of incident rheumatoid arthritis (RA) using systematic review and meta-analysis technique.

METHODS

Potentially eligible studies were identified from Medline and EMBASE databases from inception to May 2020 using search strategy that comprised of terms for "Asthma" and "Rheumatoid arthritis". Eligible cohort study must consist of one cohort of patients with asthma and another cohort of individuals without asthma. Then, the study must effect estimates with 95% confidence intervals (95% CIs) comparing incident RA between the groups. Eligible case-control studies must include cases with RA and controls without RA. Then, the study must explore their history of asthma. Odds ratio (OR) with 95% CIs of the association between asthma status and RA must be reported. Point estimates with standard errors were retrieved from each study and were combined together using the generic inverse variance method.

RESULTS

A total of 22,442 articles were identified. After two rounds of independent review by three investigators, six cohort studies and fourteen case-control studies met the eligibility criteria and were included into the meta-analysis. Meta-analysis of cohort studies found that patients with asthma had a significantly higher risk of RA compared with individuals without asthma with the pooled hazard ratio of 1.42 (95% CI, 1.18 - 1.70). Meta-analysis of case-control studies revealed that patients with asthma had a higher risk of RA compared with individuals without asthma with the pooled odds ratio of 1.33 (95%CI, 0.97 - 1.83). Funnel plot for the meta-analysis of case-control studies was asymmetric, suggesting the presence of publication bias.

CONCLUSIONS

This systematic review and meta-analysis found a significant association between asthma and higher risk of incident RA.

Patients with asthma have a higher risk of systemic lupus erythematosus: a systematic review and meta-analysis

OBJECTIVE

This study aimed to investigate the association between asthma and risk of systemic lupus erythematosus (SLE) using systematic review and meta-analysis technique.

METHODS

Potentially eligible studies were identified from Medline and EMBASE databases from inception to March 2020 using search strategy that comprised of terms for "asthma" and "systemic lupus erythematosus." Qualified cohort study must consist of one cohort of patients with asthma and another cohort of individuals without asthma. Then, the study must report relative risk (RR) with 95% confidence intervals (95% CIs) of incident SLE between the two groups. Qualified case-control studies must consist of cases with SLE and controls without SLE. Then, the study must explore their history of asthma. Odds ratio (OR) with 95% CIs of the association between asthma status and SLE must be reported. Point estimates and standard errors were extracted from each study and were combined using the generic inverse variance method.

RESULTS

A total of 21,486 articles were identified. After two rounds of independent review by three investigators, three cohort studies and seven case-control studies met the eligibility criteria and were included into the meta-analysis. Patients with asthma had a significantly higher risk of SLE compared with individuals without asthma with the pooled odds ratio of 1.37 (95% CI 1.14-1.65; I² 67%). Funnel plot was symmetric and did not suggest the presence of publication bias.

CONCLUSIONS

The current study found a significant association between asthma and increased risk of SLE. Key Points • Studies have suggested an elevated risk of systemic lupus erythematosus among patients with asthma; however, the results from existing studies are inconsistent. • This meta-analysis included data from three cohort studies and seven case--control studies. • A significant association between asthma and elevated risk of systemic lupus erythematosus was observed, with the pooled odds ratio of 1.37 (95% CI 1.14-1.65; I² 67%).

Impact of immune-mediated diseases in inflammatory bowel disease and implications in therapeutic approach

Inflammatory bowel diseases (IBD) belong to the group of immune-mediated diseases (IMIDs). The effect of associated IMIDs in the prognosis in IBD is nowadays unknown. To describe IMIDs associated to IBD patients and evaluate differences linked to the presence or absence of IMIDs. A unicentric retrospective descriptive study was designed. A cohort of 1,448 patients were categorized according to the presence of IMIDs. Clinical characteristics were obtained from IBD database. Univariate and multivariate analysis were performed. 385 patients were diagnosed with associated IMIDs while 1,063 had no associated IMIDs. A prevalence of 26.6% IMIDs associated to IBD was observed. Asthma, skin psoriasis and rheumatoid diseases were most commonly found. Factors associated to the presence of IMIDs were women (OR 1.48; 95 CI 1.17-1.87) and Crohn's disease (OR 1.35; 95 CI 1.07-1.70). Patients with associated IMIDs required more immunomodulator (OR 1.61; 95 CI 1.27-2.43) and biological treatment (OR 1.81; 95 CI 1.47-2.43). More surgical risk was observed in multivariate analysis in those patients diagnosed with IMIDs prior to the onset of IBD (OR 3.71; 95% CI 2.1-6.56). We considered the presence of IMIDs a poor prognostic factor and suggest a closer monitoring of these patients.

Risk of Prevalent Asthma among Children Affected by Inflammatory Bowel Disease: A Population-Based Birth Cohort Study

Literature on the risk of asthma among children with inflammatory bowel disease (IBD) is limited and has reported discording results. To the best of our knowledge, no previous study has evaluated the association between asthma and childhood onset IBD, focusing on pediatric IBD with onset between 10 and 17 years, early-onset IBD (EO-IBD) between 0 and 9 years, and very early-onset IBD (VEO-IBD) between 0 and 5 years, all conditions characterized by different clinical progressions. A nested matched case-control design on a longitudinal cohort of 213,515 newborns was adopted. Conditional binomial regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) of asthma among children with IBD compared with controls. We found 162 children with IBD and 1620 controls. Overall, childhood onset IBD was associated with increased risks of being affected by asthma (OR: 1.49 95% CI 1.05–2.12), although a significant risk was only present among males (OR: 1.60 95% CI 1.02–2.51). Children with Crohn’s disease and ulcerative colitis had similarly increased risks, although they failed to attain statistical significance. Risks of asthma based on age at IBD onset were inversely related to age, with the lowest non-significant risks for pediatric IBD and EO-IBD, while children affected by VEO-IBD had the highest risk of asthma (OR: 2.75 95% CI 1.26–6.02). Our study suggests the presence of a higher prevalence of asthma among both male children with IBD and children with VEO-IBD. It could be advisable to pay greater attention to possible respiratory symptoms among these categories at higher risk.

Comorbidities in adolescents with inflammatory bowel disease: findings from a population-based cohort study

BACKGROUND

Inflammatory bowel diseases are associated with various immune- and non-immune-mediated conditions. We aimed to assess the association of inflammatory bowel diseases with comorbidities at late adolescence.

METHODS

Jewish Israeli adolescents who underwent a general health evaluation prior to enlistment to the Israeli Defense Forces from 2002 to 2016 were included.

RESULTS

Overall, 891 subjects (595 Crohn's disease, 296 ulcerative colitis, median age 17.1 years) and 1,141,841 controls were analyzed. Crohn's disease was associated with arthritis (odds ratio (OR) 4.7, 95% confidence interval (CI) 2.4-9.1), thyroid disease (OR 2.6, 95% CI 1.2-5.5), atopic dermatitis (OR 2, 95% CI 1.1-3.6), autoimmune hepatitis (OR 4.4, 95% CI 2.3-8.6), nephrolithiasis (OR 3.6, 95% CI 1.2-11.4), and pancreatitis (OR 41.8, 95% CI 17.2-101.9). Ulcerative colitis was associated with arthritis (OR 3.6, 95% CI 1.0-9.8), thyroid disease (OR 4.8, 95% CI 1.2-19.4), autoimmune hepatitis (OR 8, 95% CI 4-16.2), and pancreatitis (OR 51, 95% CI 16.1-158.9). Primary sclerosing cholangitis was associated with both diseases. Asthma, celiac, type 1 diabetes, psoriasis, and bone fractures were not more common in both diseases. Male predominance was noted for most associations.

CONCLUSIONS

At adolescence, both Crohn's disease and ulcerative colitis are associated with multiple comorbidities, not limited to autoimmune disorders.