Coeliac disease and asthma association in children: the role of antibiotic consumption

Causal association between allergic diseases and celiac disease: a bidirectional two-sample and multivariable Mendelian-randomization study

OBJECTIVE

This study aimed to assess the causality of allergic diseases and celiac disease.

METHODS

We collected summary-level data from publicly available genome-wide association studies to conduct our bidirectional two-sample and multivariable Mendelian randomization analysis. Furthermore, a series of sensitivity analyses were applied to validate our findings.

RESULTS

In bidirectional two-sample MR analyses, we found a significant causal effect of atopic dermatitis (AD) on CD (Inverse-variance weighted (IVW): odds ratio [OR] = 1.302, 95% confidence interval [CI] = 1.152-1.471, p < 0.001). We also found a significant causal effect of allergic rhinitis (AR) on CD (IVW: OR = 4.181, 95% CI = 1.495-11.697, p = 0.006). However, the MR-Egger method indicated a different causal effect direction compared to the IVW and weighted median method. After Bonferroni correction, the result of asthma on CD is suggestive of a causal effect (IVW: OR = 1.186, 95% CI = 1.021-1.378, p = 0.026). No causal effects were found when CD was considered as an exposure variable. In MVMR analyses, after separately and jointly adjusting for the influence of smoking and BMI, the causal effect of AD on CD remained robust.

CONCLUSIONS

Our study suggests that AD is a risk factor for CD and it is considered suggestive of a causal relationship between asthma and CD. Further research is needed to explore the potential mechanisms underlying this causal effect.

Causal relationships between autoimmune diseases and celiac disease: A Mendelian randomization analysis

The aim of this study was to investigate the causal relationship between autoimmune disorders and celiac disease (CeD) through Mendelian randomization (MR). Single nucleotide polymorphisms (SNPs) significantly associated with 13 autoimmune diseases were extracted from the summary statistics of European genome-wide association studies (GWAS), and their effects were examined by Inverse variance-weighted (IVW) in a large European GWAS on CeD. Finally, reverse MR was performed to investigate the causal effects of CeD on autoimmune traits. Following the application of Bonferroni correction for multiple testing, genetically determined seven autoimmune diseases are causally associated with CeD: Crohn's disease (CD) (OR [95%CI] = 1.156 [1.106 ± 1.208], P = 1.27E-10), primary biliary cholangitis (PBC) (1.229 [1.143 ± 1.321], P = 2.53E-08), primary sclerosing cholangitis (PSC) (1.688 [1.466 ± 1.944], P = 3.56E-13), rheumatoid arthritis (RA) (1.231 [1.154 ± 1.313], P = 2.74E-10), systemic lupus erythematosus (SLE) (1.127 [1.081 ± 1.176], P = 2.59E-08), type 1 diabetes (T1D) (1.41 [1.238 ± 1.606], P = 2.24E-07), and asthma (1.414 [1.137 ± 1.758], P = 1.86E-03). The IVW analysis indicated that CeD increased the risk for seven diseases: CD (1.078 [1.044 ± 1.113], P = 3.71E-06), Graves' disease (GD) (1.251 [1.127 ± 1.387], P = 2.34E-05), PSC (1.304 [1.227 ± 1.386], P = 8.56E-18), psoriasis (PsO) (1.12 [1.062 ± 1.182], P = 3.38E-05), SLE (1.301[1.22 ± 1.388], P = 1.25E-15), T1D (1.3[1.228 ± 1.376], P = 1.57E-19), and asthma (1.045 [1.024 ± 1.067], P = 1.82E-05). The sensitivity analyses deemed the results reliable without pleiotropy. There are positive genetic correlations between various autoimmune diseases and CeD, and the latter also affects the predisposition to multiple autoimmune disorders in the European population.

Allergy and autoimmunity in children: non-mutually exclusive diseases. A narrative review

In last decades a simultaneous increase in the prevalence of atopic and autoimmune disorders in pediatric population has been observed. Despite the Th1-Th2 paradigm, supporting the polarization of the immune system with Th1 response involved in autoimmune diseases and Th2 response leading to hypersensitivity reactions, recent evidence suggests a possible coexistence of common pathogenic pathways as result of shared immune dysregulation. Similar genes and other mechanisms such as epithelial barrier damage, gut microbiota dysbiosis and reduced number of T regs and IL-10 contribute to the onset of allergy and autoimmunity. IgA deficiency is also hypothesized to be the crosslink between celiac disease and allergy by lowering gut mucous membrane protection from antigens and allergens. The present narrative review aims to give an overview of the co-occurrence of allergic and autoimmune disorders (celiac disease, inflammatory bowel diseases, type 1 diabetes mellitus, thyroid disease, juvenile idiopathic arthritis) in pediatric population, based on the available evidence. We also highlighted the common pathogenic pathways that may underpin both. Our findings confirm that allergic and autoimmune diseases are commonly associated, and clinicians should therefore be aware of the possible coexistence of these conditions in order to ameliorate disease management and patient care. Particular attention should be paid to the association between atopic dermatitis or asthma and celiac disease or type 1 diabetes and vice versa, for therapeutic interventions. Further studies are needed to better clarify mechanisms involved in the pathogenesis and eventually identify new therapeutic strategies.

Revealing polygenic pleiotropy using genetic risk scores for asthma

In this study we examined how genetic risk for asthma associates with different features of the disease and with other medical conditions and traits. Using summary statistics from two multi-ancestry genome-wide association studies of asthma, we modeled polygenic risk scores (PRSs) and validated their predictive performance in the UK Biobank. We then performed phenome-wide association studies of the asthma PRSs with 371 heritable traits in the UK Biobank. We identified 228 total significant associations across a variety of organ systems, including associations that varied by PRS model, sex, age of asthma onset, ancestry, and human leukocyte antigen region alleles. Our results highlight pervasive pleiotropy between asthma and numerous other traits and conditions and elucidate pathways that contribute to asthma and its comorbidities.

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.

Risk perception and knowledge of COVID-19 in patients with celiac disease

BACKGROUND

We recently demonstrated that the odds of contracting coronavirus disease 2019 (COVID-19) in patients with celiac disease (CeD) is similar to that of the general population. However, how patients with CeD perceive their COVID-19 risk may differ from their actual risk.

AIM

To investigate risk perceptions of contracting COVID-19 in patients with CeD and determine the factors that may influence their perception.

METHODS

We distributed a survey throughout 10 countries between March and June 2020 and collected data on demographics, diet, COVID-19 testing, and risk perceptions of COVID-19 in patients with CeD. Participants were recruited through various celiac associations, clinic visits, and social media. Risk perception was assessed by asking individuals whether they believe patients with CeD are at an increased risk of contracting COVID-19 when compared to the general population. Logistic regression was used to determine the influencing factors associated with COVID-19 risk perception, such as age, sex, adherence to a gluten-free diet (GFD), and comorbidities such as cardiac conditions, respiratory conditions, and diabetes. Data was presented as adjusted odds ratios (aORs)

RESULTS

A total of 10737 participants with CeD completed the survey. From them, 6019 (56.1%) patients with CeD perceived they were at a higher risk or were unsure if they were at a higher risk of contracting COVID-19 compared to the non-CeD population. A greater proportion of patients with CeD perceived an increased risk of contracting COVID-19 when compared to infections in general due to their CeD (56.1% vs 26.7%, P < 0.0001). Consequently, 34.8% reported taking extra COVID-19 precautions as a result of their CeD. Members of celiac associations were less likely to perceive an increased risk of COVID-19 when compared to non-members (49.5% vs 57.4%, P < 0.0001). Older age (aOR: 0.99; 95%CI: 0.99 to 0.99, P < 0.001), male sex (aOR: 0.84; 95%CI: 0.76 to 0.93, P = 0.001), and strict adherence to a GFD (aOR: 0.89; 95%CI: 0.82 to 0.96, P = 0.007) were associated with a lower perception of COVID-19 risk and the presence of comorbidities was associated with a higher perception of COVID-19 risk (aOR: 1.38; 95%CI: 1.22 to 1.54, P < 0.001).

CONCLUSION

Overall, high levels of risk perceptions, such as those found in patients with CeD, may increase an individual’s pandemic-related stress and contribute to negative mental health consequences. Therefore, it is encouraged that public health officials maintain consistent communication with the public and healthcare providers with the celiac community. Future studies specifically evaluating mental health in CeD could help determine the consequences of increased risk perceptions in this population.

Respiratory

Lung disease rivals the position for the top cause of death worldwide. Causes and pathology of the myriad lung diseases are varied, yet nutrition can either affect the outcome or support treatment in the majority of cases. This chapter explores the modifiable risk factors, from lifestyle changes to dietary intake to specific nutrients, anti-nutrients, and toxins helpful for the nutritionist or dietitian working with lung disease patients. General lung health is discussed, and three major disease states are explored in detail, including alpha-1 antitrypsin deficiency, asthma, and idiopathic pulmonary fibrosis. Although all lung diseases have diverse causes, many integrative and functional medical nutrition therapies are available and are not being utilized in practice today. This chapter begins the path toward better nutrition education for the integrative and functional medicine professional.

Association between early life (prenatal and postnatal) antibiotic administration and coeliac disease: a systematic review

OBJECTIVE

Whether prenatal or postnatal exposure to antibiotics is associated with an increased risk of coeliac disease (CD) is unclear. We systematically reviewed studies on the association between early life antibiotic exposure and the risk of CD or CD autoimmunity.

DESIGN

Systematic review of observational studies.

DATA SOURCES

The PubMed and Embase databases were searched up to December 2018, with no language restrictions. Additional references were obtained from reviewed articles.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Cohort, cross-sectional and case-control studies that assessed the association between prenatal and/or postnatal antibiotic exposure and the odds of developing CD (as defined by authors of the original studies) or CD autoimmunity were eligible for inclusion.

RESULTS

Six studies were included. In two large cohort studies that focused on prenatal antibiotic exposure, no association with the risk of CD was found (adjusted OR=1.16; 95% CI 0.94 to 1.43 and adjusted HR=1.33; 95% CI 0.69 to 2.56) in the Norwegian and Swedish cohorts, respectively. In three studies that evaluated the association of postnatal antibiotic exposure with the risk of CD, the results were contradictory, with only the Italian cohort study reporting a significant positive association (adjusted incidence rate ratio=1.24; 95% CI 1.07 to 1.43). A large, multicentre cohort study that evaluated the association between postnatal antibiotic exposure and CD autoimmunity in human leukocyte antigen (HLA)-positive subjects found no association.

CONCLUSIONS

We found no evidence of an association between prenatal or postnatal antibiotic exposure and CD.

Follow up on atopy and the gastrointestinal tract - a review of a common association 2018

Primary atopic disorders can be classified as heritable genetic disorders presenting with deregulated pathogenic allergic effector responses irrespective of sensitization. In the last decade, there are parallel rises in the burden of atopic and gastrointestinal (GI) diseases. Areas covered: There is increasing recognition of an association between atopy and GI disease through immune dysregulation, the microbiome and shared genetic pathways. Since the first article on atopy and the GI tract in 2014 in this journal, many more studies have shed light on the shared pathways in these diseases, particularly in the field of eosinophilic GI disease, functional GI disorders, and inflammatory bowel disease. Expert opinion: Understanding the links with common mechanisms in atopy and GI diseases that may lead to better targeting of treatment through manipulation of immune mechanisms, the microbiome, genetics, food allergens and specific GI diseases such as inflammatory bowel disease, functional GI disorders.

Extraintestinal Manifestations of Celiac Disease: Early Detection for Better Long-Term Outcomes

Population-based screening studies have shown celiac disease to be one of the most common chronic gastrointestinal diseases. Nevertheless, because of the diverse clinical presentation, the great majority of patients remain unrecognized. Particularly difficult to identify are the multifaceted extraintestinal symptoms that may appear at variable ages. Although the pathogenesis and long-term outcome of these manifestations are still poorly established, there is some evidence that unrecognized celiac disease predisposes to severe complications if not diagnosed and prevented with an early-initiated gluten-free diet. Therefore, it is of utmost importance that physicians of different disciplines learn to recognize celiac disease in individuals with non-gastrointestinal symptoms. In the future, more studies are needed to clarify the factors affecting development and prognosis of the extraintestinal manifestations.

Celiac Disease by the Age of 13 Years Is Not Associated With Probiotics Administration in Infancy

Probiotics are theoretically promising in primary prevention of celiac disease (CD), but research evidence on the topic is scarce. We used the data and material of a clinical double-blind randomized placebo-controlled trial on primary allergy prevention (n = 1223) to investigate in an exploratory study whether administration of a mix of pro- and prebiotics during late pregnancy and first 6 months of life was associated with prevalence of CD during 13-year follow-up. Children who fulfilled diagnostic criteria for CD (n = 11) and subjects with a serum sample available for analyzing CD antibodies (n = 867) were included. CD or elevated tissue transglutaminase IgA antibodies were not associated with probiotics or placebo. Nor were there any associations with the mode of delivery, the duration of exclusive or total breast-feeding, or respiratory infections during the first 2 years of life. Allergic diseases or sensitization by the age of 2 or 5 years were not clearly associated with the development of CD.

Genetics, environment, and asthma associated with celiac disease in the extended family of an affected child

INTRODUCTION

Celiac disease (CD) is an autoimmune enteropathy associated with gluten ingestion. In extended families of celiac patients that live in close proximity of one another, shared genetic and environmental factors can predispose them to CD.

AIM

The aim of this study was to provide evidence about the genetic and environmental factors involved in the development of CD in the extended family of a pediatric patient.

METHODS

The medical history, environmental conditions, and participant weight, height, and peripheral blood samples were evaluated. The HLA-DQ2/DQ8 haplotypes were genotyped through qPCR testing and the IgA anti-gliadin and anti-transglutaminase antibodies were quantified using the ELISA test.

RESULTS

Twelve close-living maternal relatives of the index case participated in the study. Eight of them presented with the HLA-DQ2 haplotype, inherited from the grandfather, and 7/12 and 9/12 were positive for IgA anti-gliadin and IgA anti-transglutaminase antibodies, respectively. The main intestinal symptoms stated by the participants were abdominal bloating, excess flatulence, constipation, and gastroesophageal reflux. The most frequent extra-intestinal symptoms were fatigue, stress, and anxiety. In addition, 6/13 participants had bronchial asthma.

CONCLUSION

The extended family living in close proximity of one another shared a genetic predisposition, environmental conditions, and asthma, which could have predisposed them to celiac disease.

Association of Asthma with Rheumatoid Arthritis: A Population-Based Case-Control Study

BACKGROUND

T_H1 and T_H2 cells have counterregulatory relationships. However, the relationship between asthma, a T_H2-predominant condition, and risk of systemic inflammatory diseases such as rheumatoid arthritis (RA), a T_H1 condition, is poorly understood.

OBJECTIVE

We aimed to determine whether asthma was associated with increased risks of incident RA among adults.

METHODS

We conducted a retrospective population-based case-control study that examined existing incident RA cases and controls matched by age, sex, and registration year from the general population in Olmsted County, Minnesota, between January 2002 and December 2007. We performed comprehensive medical record reviews to ascertain asthma status using predetermined asthma criteria. The frequency of a history of asthma before the index date was compared between cases and controls. Logistic regression models were used to adjust for confounding factors.

RESULTS

We enrolled 221 RA cases and 218 controls. Of the 221 RA cases, 156 (70.6%) were females, 207 (93.7%) were white, the median age at the index date was 52.5 years, and 53 (24.0%) had a history of asthma. Controls had similar characteristics except that 35 of 218 controls (16.1%) had a history of asthma. After adjustment for sex, age, smoking, body mass index, socioeconomic status, and comorbidity, asthma was significantly associated with increased risks of RA (adjusted odds ratio, 1.74; 95% CI, 1.05-2.90; P = .03).

CONCLUSIONS

Despite the counterregulatory relationship between T_H1 and T_H2 cells, patients with asthma had a significantly higher risk of developing RA than healthy individuals.

Prevalence, incidence and associated comorbidities of treated hypothyroidism: an update from a European population

OBJECTIVE

Estimates of the prevalence of hypothyroidism in unselected populations date from the late 1990s. We present an update on the prevalence and incidence of overt hypothyroidism in Piedmont, northwest Italy and examine the association between hypothyroidism and multiple chronic comorbidities.

DESIGN AND METHODS

Data were obtained from drug prescription and hospital discharge databases. Individuals who had received at least two levothyroxine prescriptions in 2012 were defined as having hypothyroidism; those who had undergone thyroidectomy or I¹³¹ irradiation in the previous 5 years were defined as having iatrogenic hypothyroidism and those who had either obtained exemption from treatment co-payment or had been discharged from hospital with a chronic comorbidity (diabetes and connective tissue diseases) were identified as having one of these conditions.

RESULTS

The overall crude prevalence was 31.1/1000 (2.3/1000 for iatrogenic hypothyroidism) and the overall crude incidence was 7/1000. The average daily dose of thyroxine (122 µg) roughly corresponded to 1.7 µg/kg. There was a strong association between hypothyroidism and diabetes (type 1, type 2 or gestational) and with autoimmune diseases, with the odds ratio ranging from 1.43 (1.02-1.99) for psoriatic arthritis to 4.99 (3.06-8.15) for lupus erythematosus.

CONCLUSIONS

As compared with previous estimates, the prevalence of hypothyroidism rose by about 35%, driven mainly by non-iatrogenic forms. The increase may be due to either population aging or improved diagnostic capability or both. The frequent co-occurrence of hypothyroidism with other multiple chronic conditions characterizes it more as a comorbidity rather than an isolated chronic disease.