Multiple sclerosis and celiac disease: is there an increased risk?

Is Celiac Disease (CD) Prevalent in Patients with Multiple Sclerosis (MS): A Systematic Review and Meta-Analysis

Background. Celiac disease (CD) is an autoimmune disease, and its prevalence reported variously in different studies. The goal of this study is to evaluate the pooled prevalence of CD in subjects with MS. Methods. PubMed, Scopus, EMBASE, Web of Science, and Google Scholar along with gray literature were systematically searched. The search included all relevant studies which were published up to October 2022. Two researchers independently searched all databases and also references of included studies. Results. We found 8211 articles by literature search, and after deleting duplicates, 5594 remained. Fifteen articles remained for meta-analysis. Totally, 31418 patients were evaluated, and the total number of possible/confirmed cases was 124. Studies were published between 2004 and 2020, and the most published studies were from Italy. Five studies provided information regarding controls. The total number of controls was 22394, of whom 22 had CD. Mean age ranged from 35 to 55 years. The pooled prevalence of CD in MS patients was 0 ( $I^2=88.2$ %, $p<0.001$ ). The pooled odds of CD in subjects with MS are 0.46 (95% CI: 0.19-1.1) ( $I^2=0$ , $p=0.9$ ). Conclusion. The pooled prevalence of this systematic review showed that CD is not prevalent in MS cases.

Current Evidence on the Efficacy of Gluten-Free Diets in Multiple Sclerosis, Psoriasis, Type 1 Diabetes and Autoimmune Thyroid Diseases

In this review, we summarize the clinical data addressing a potential role for gluten in multiple sclerosis (MS), psoriasis, type 1 diabetes (T1D) and autoimmune thyroid diseases (ATDs). Furthermore, data on the prevalence of celiac disease (CD) and gluten-related antibodies in the above patient groups are presented. Adequately powered and properly controlled intervention trials investigating the effects of a gluten-free diet (GFD) in non-celiac patients with MS, psoriasis, T1D or ATDs are lacking. Only one clinical trial has studied the effects of a GFD among patients with MS. The trial found significant results, but it is subject to major methodological limitations. A few publications have found beneficial effects of a GFD in a subgroup of patients with psoriasis that were seropositive for anti-gliadin or deamidated gliadin antibodies, but no effects were seen among seronegative patients. Studies on the role of gluten in T1D are contradictive, however, it seems likely that a GFD may contribute to normalizing metabolic control without affecting levels of islet autoantibodies. Lastly, the effects of a GFD in non-celiac patients with ATDs have not been studied yet, but some publications report that thyroid-related antibodies respond to a GFD in patients with concomitant CD and ATDs. Overall, there is currently not enough evidence to recommend a GFD to non-celiac patients with MS, psoriasis, ATDs or T1D.

Transplantation of fecal microbiota rich in short chain fatty acids and butyric acid treat cerebral ischemic stroke by regulating gut microbiota

The gut microbiota and its short chain fatty acid (SCFA) metabolites have been established to play an important protective role against neurodegenerative diseases. Our previous study demonstrated that cerebral ischemic stroke triggers dysfunctional gut microbiota and increased intestinal permeability. In this study, we aimed to clarify the mechanism by which gut microbiota and SCFAs can treat cerebral ischemic stroke in rat middle cerebral artery occlusion models and use the information to develop new therapies. Our results show that oral administration of non-absorbable antibiotics reduced neurological impairment and the cerebral infarct volume, relieved cerebral edemas, and decreased blood lipid levels by altering the gut microbiota. We also found that ischemic stroke decreased intestinal levels of SCFAs. And that transplanting fecal microbiota rich in these metabolites was an effective means of treating the condition. Compared with other SCFAs, butyric acid showed the highest negative correlation with ischemic stroke. Supplementation with butyric acid treated models of ischemic stroke effectively by remodeling the gut microbiota, enriching the beneficial Lactobacillus, and repairing the leaky gut. In conclusion, interfering with the gut microbiota by transplanting fecal bacteria rich in SCFAs and supplementing with butyric acid were found to be effective treatments for cerebral ischemic stroke.

The intestinal barrier in multiple sclerosis: implications for pathophysiology and therapeutics

Biological barriers are essential for the maintenance of homeostasis in health and disease. Breakdown of the intestinal barrier is an essential aspect of the pathophysiology of gastrointestinal inflammatory diseases, such as inflammatory bowel disease. A wealth of recent studies has shown that the intestinal microbiome, part of the brain-gut axis, could play a role in the pathophysiology of multiple sclerosis. However, an essential component of this axis, the intestinal barrier, has received much less attention. In this review, we describe the intestinal barrier as the physical and functional zone of interaction between the luminal microbiome and the host. Besides its essential role in the regulation of homeostatic processes, the intestinal barrier contains the gut mucosal immune system, a guardian of the integrity of the intestinal tract and the whole organism. Gastrointestinal disorders with intestinal barrier breakdown show evidence of CNS demyelination, and content of the intestinal microbiome entering into the circulation can impact the functions of CNS microglia. We highlight currently available studies suggesting that there is intestinal barrier dysfunction in multiple sclerosis. Finally, we address the mechanisms by which commonly used disease-modifying drugs in multiple sclerosis could alter the intestinal barrier and the microbiome, and we discuss the potential of barrier-stabilizing strategies, including probiotics and stabilization of tight junctions, as novel therapeutic avenues in multiple sclerosis.

The role of gluten in multiple sclerosis: A systematic review

BACKGROUND

There is an increasing interest in diet as a modifying factor in multiple sclerosis (MS), and gluten has been suggested to affect MS.

OBJECTIVE

The aim of this systematic review is to qualitatively evaluate the evidence on the role of gluten in MS.

METHODS

A review protocol was submitted to PROSPERO. A systematic literature search was conducted in PubMed, Web of Science, Scopus, Embase, Cab Abstracts, and Google Scholar. Studies on patients with MS, clinically isolated syndrome, or celiac disease presenting with MS-related markers were included, if they investigated effects of diets containing specified amounts of gluten or associations between gluten sensitivities and MS.

RESULTS

Forty-nine publications presenting 50 studies/cases met the inclusion criteria. Study designs, methods, and outcomes varied broadly across studies. Two intervention studies found a positive effect of a gluten-free diet on disease-related markers in patients with MS. One prospective cohort study also found a positive effect of a gluten-free diet, while a survey found intake of cereal/bread to be protective against MS. Four observational studies did not find increased comorbidity of MS and celiac disease. Seventeen studies investigated the level of different gluten-sensitivity markers in patients with MS with inconsistent results. Finally, 12 cases and 13 posters/abstracts/master's theses contributed to shed light on the topic.

CONCLUSIONS

There is still not sufficient evidence to state whether gluten plays a role in MS, but limitations of current evidence have been identified and directions of future research have been suggested.

Intestinal Permeability in Relapsing-Remitting Multiple Sclerosis

Changes of intestinal permeability (IP) have been extensively investigated in inflammatory bowel diseases (IBD) and celiac disease (CD), underpinned by a known unbalance between microbiota, IP and immune responses in the gut. Recently the influence of IP on brain function has greatly been appreciated. Previous works showed an increased IP that preceded experimental autoimmune encephalomyelitis development and worsened during disease with disruption of TJ. Moreover, studying co-morbidity between Crohn's disease and MS, a report described increased IP in a minority of cases with MS. In a recent work we found that an alteration of IP is a relatively frequent event in relapsing-remitting MS, with a possible genetic influence on the determinants of IP changes (as inferable from data on twins); IP changes included a deficit of the active mechanism of absorption from intestinal lumen. The results led us to hypothesize that gut may contribute to the development of MS, as suggested by another previous work of our group: a population of CD8+CD161high T cells, belonging to the mucosal-associated invariant T (MAIT) cells, a gut- and liver-homing subset, proved to be of relevance for MS pathogenesis. We eventually suggest future lines of research on IP in MS: studies on IP changes in patients under first-line oral drugs may result useful to improve their therapeutic index; correlating IP and microbiota changes, or IP and blood-brain barrier changes may help clarify disease pathogenesis; exploiting the IP data to disclose co-morbidities in MS, especially with CD and IBD, may be important for patient care.

Serological prevalence of celiac disease in Brazilian population of multiple sclerosis, neuromyelitis optica and myelitis

PURPOSE

Comorbidity of celiac disease with demyelinating diseases of the central nervous system has been reported since the 1960s. The objective of this study was to determine the serological prevalence of celiac disease in the largest series of patients diagnosed with multiple sclerosis, neuromyelitis optica, or myelitis.

METHODS

A prevalence study was conducted with patients evaluated at Sarah Network of Rehabilitation Hospitals between March 2012 and September 2013. They were previously diagnosed with multiple sclerosis, neuromyelitis optica, or idiopathic myelitis. The serum levels of antibodies against tissue transglutaminase and endomysium were assessed.

RESULTS

Of the 379 patients evaluated, 249 (65.70%) were diagnosed with multiple sclerosis, 37 (9.56%) with neuromyelitis optica, and 96 (24.54%) with idiopathic myelitis. Two patients (0.53%), one with multiple sclerosis and other with myelitis, tested positive for both antibodies.

CONCLUSION

Our study do not confirm the relationship between celiac serological antibodies with multiple sclerosis, neuromyelitis optica and inflammatory myelitis of an unknown etiology.

A systematic review of the incidence and prevalence of comorbidity in multiple sclerosis: overview

Background:

Comorbidity is an area of increasing interest in multiple sclerosis (MS).

Objective:

The objective of this review is to estimate the incidence and prevalence of comorbidity in people with MS and assess the quality of included studies.

Methods:

We searched the PubMed, SCOPUS, EMBASE and Web of Knowledge databases, conference proceedings, and reference lists of retrieved articles. Two reviewers independently screened abstracts. One reviewer abstracted data using a standardized form and the abstraction was verified by a second reviewer. We assessed study quality using a standardized approach. We quantitatively assessed population-based studies using the I² statistic, and conducted random-effects meta-analyses.

Results:

We included 249 articles. Study designs were variable with respect to source populations, case definitions, methods of ascertainment and approaches to reporting findings. Prevalence was reported more frequently than incidence; estimates for prevalence and incidence varied substantially for all conditions. Heterogeneity was high.

Conclusion:

This review highlights substantial gaps in the epidemiological knowledge of comorbidity in MS worldwide. Little is known about comorbidity in Central or South America, Asia or Africa. Findings in North America and Europe are inconsistent. Future studies should report age-, sex- and ethnicity-specific estimates of incidence and prevalence, and standardize findings to a common population.

The incidence and prevalence of comorbid gastrointestinal, musculoskeletal, ocular, pulmonary, and renal disorders in multiple sclerosis: A systematic review

Background:

As new disease-modifying therapies emerge a better knowledge of the risk of comorbid disease in multiple sclerosis (MS) is needed.

Objective:

To estimate the incidence and prevalence of comorbid gastrointestinal, musculoskeletal, ocular, pulmonary, and renal disorders in MS.

Methods:

We systematically reviewed the world literature by searching PUBMED, EMBASE, SCOPUS, the Web of Knowledge, and reference lists of retrieved articles. For selected articles, one reviewer abstracted data using a standardized form. The abstraction was verified by a second reviewer. The quality of all selected studies was assessed. For population-based studies we quantitatively assessed studies using the I² statistic, and conducted random effects meta-analyses.

Results:

Study designs were heterogeneous with respect to populations, case definitions, and methods of ascertainment. Incidence of the studied comorbidities was rarely reported. Irritable bowel syndrome and chronic lung disease had a prevalence of more than 10% in the MS population. Irritable bowel syndrome, fibromyalgia, cataracts and glaucoma were more common than expected in the MS population.

Conclusion:

Although they have been the subject of less study than other comorbidities, irritable bowel syndrome, arthritis, and chronic lung disease are common in the MS population and occur more often than expected when compared to the general population.

A systematic review of the incidence and prevalence of autoimmune disease in multiple sclerosis

Background:

As new therapies emerge which increase the risk of autoimmune disease it is increasingly important to understand the incidence of autoimmune disease in multiple sclerosis (MS).

Objective:

The purpose of this review is to estimate the incidence and prevalence of comorbid autoimmune disease in MS.

Methods:

The PUBMED, EMBASE, SCOPUS and Web of Knowledge databases, conference proceedings, and reference lists of retrieved articles were searched, and abstracts were independently screened by two reviewers. The data were abstracted by one reviewer using a standardized data collection form, and the findings were verified by a second reviewer. We assessed quality of the included studies using a standardized approach and conducted meta-analyses of population-based studies.

Results:

Sixty-one articles met the inclusion criteria. We observed substantial heterogeneity with respect to the populations studied, methods of ascertaining comorbidity, and reporting of findings. Based solely on population-based studies, the most prevalent autoimmune comorbidities were psoriasis (7.74%) and thyroid disease (6.44%). Our findings also suggest an increased risk of inflammatory bowel disease, likely uveitis and possibly pemphigoid.

Conclusion:

Fewer than half of the studies identified were of high quality. Population-based studies that report age, sex and ethnicity-specific estimates of incidence and prevalence are needed in jurisdictions worldwide.

Higher relative risk for multiple sclerosis in a pediatric and adolescent diabetic population: analysis from DPV database

OBJECTIVE Type 1 diabetes and multiple sclerosis (MS) are typical autoimmune diseases in children and young adults. We assessed the co-occurrence of type 1 diabetes and MS by estimating the relative risk (RR) for MS in a pediatric and adolescent diabetic population and looked for possible influencing factors. RESEARCH DESIGN AND METHODS Within the Diabetes Patienten Verlaufsdokumentation (DPV)-Wiss Project, from January 1995 to October 2012, data from 56,653 patients with type 1 diabetes were collected in 248 centers in Germany and Austria. Published data on German and Mid-European MS prevalence were taken for comparison. Multivariable regression analysis was used to identify confounders for co-occurrence of type 1 diabetes and MS. RESULTS The RR for MS in patients with type 1 diabetes was estimated at 3.35-4.79 (95% CI 1.56-7.21 and 2.01-11.39, respectively). Immigration status in all patients (P < 0.05) and the presence of thyroid antibodies in male patients only (P = 0.05) were identified as influencing factors on MS incidence within the DPV database. The month-of-birth pattern revealed that risk was higher during the spring and summer months in the population with type 1 diabetes and MS in comparison with the population with type 1 diabetes. CONCLUSIONS The present cohort study demonstrates a higher risk of co-occurrence of MS in a pediatric and adolescent diabetic population. Immigration status and thyroid antibodies in male patients were independent risk indicators for the incidental rate of MS. Diabetic patients born during spring and summer had a higher risk for the development of MS. We suggest that environmental factors modulate the individual's risk for the co-occurrence of both diseases.

[Gluten-related disorders and demyelinating diseases]

Gluten-related disorders are a spectrum of systemic immune mediated conditions that occur at any age in genetically susceptible individuals upon ingesting gluten. Celiac disease and gluten sensitivity are the most important conditions of the spectrum. They may be associated with other autoimmune diseases, such as multiple sclerosis and neuromyelitis optica. Treatment with a gluten-free diet can provide considerable benefits to the patients having both a gluten-related disorder and one of these 2 demyelinating diseases of the central nervous system.

Gluten sensitivity in multiple sclerosis: experimental myth or clinical truth?

Patients with neurological disease of unknown etiology sometimes present with antigliadin and antitissue transglutaminase antibodies. The association between these antibodies and multiple sclerosis has been previously suggested. The purpose of this study was to determine the prevalence of these antibodies in multiple sclerosis patients. We determined the level of serum immunoglobulin A and immunoglobulin G antigliadin and antitissue transglutaminase antibodies in 98 patients with multiple sclerosis. We found a highly significant increase in titers of immunoglobulin G antibodies against gliadin and tissue transglutaminase in the multiple sclerosis patients. Seven patients had a positive IgG AGA, whereas only 2 controls presented positive titers (P = 0.03). Four patients had positive IgG anti-tTG while all the controls tested negative (P = 0.02). However, immunoglobulin A antibodies against gliadin and tissue transglutaminase were not statistically higher in the multiple sclerosis group in comparison to the control group. Our findings support the associations between antibodies against gliadin and tissue transglutaminase to multiple sclerosis. The specific role of these antibodies in the pathogenesis of multiple sclerosis remains uncertain and requires additional research. A gluten free diet should be considered in specific cases of patients who present with gluten antibodies.

Frequency of celiac disease is not increased among multiple sclerosis patients

We evaluated the presence of IgA and IgG celiac disease-related antibodies in a sample of 217 patients with multiple sclerosis (MS) and in a sample of 200 controls not affected by neurological disorders. None of the 217 patients with MS presented IgG and IgA anti-gliadin, anti-endomysial antibodies, anti-tissue transglutaminase and anti-reticulin, whereas only one of the selected controls presented specific antibodies; this subject resulted to be effectively affected by celiac disease. Our data did not show an increased frequency of celiac disease among patients with MS.

A population-based study of coeliac disease, neurodegenerative and neuroinflammatory diseases

BACKGROUND

It has been suggested that coeliac disease (CD) is associated with several neurological diseases. However, the evidence of such an association is inconclusive as earlier research has often been based on small numbers with retrospective data collection.

AIM

To use Cox regression to examine the risk of neurological disease in individuals with CD.

METHODS

Through Swedish national registers we identified some 14 000 individuals with a diagnosis of CD (1964-2003) and 70 000 reference individuals matched for age, sex, calendar year and county.

RESULTS

Coeliac disease was associated with later polyneuropathy [hazard ratio (HR) = 3.4; 95% CI = 2.3-5.1]. We found no statistically significant association between CD and subsequent multiple sclerosis (HR = 0.9; 95% CI = 0.3-2.3), Parkinson's disease (HR = 1.2; 95% CI = 0.8-1.9), Alzheimer's disease (HR = 1.5; 95% CI = 0.9-2.6), hereditary ataxia (HR = 1.3; 95% CI = 0.5-3.6), the symptom ataxia (HR = 1.9; 95% CI = 0.6-6.2), Huntington's disease (HR = 1.7; 95% CI = 0.3-8.6), myasthenia gravis (HR = 0.8; 95% CI = 0.2-3.8) or spinal muscular atrophy (HR = 0.5; 95% CI = 0.1-3.8). Prior polyneuropathy was associated with subsequent CD (odds ratio = 5.4; 95% CI = 3.6-8.2).

CONCLUSIONS

The association between CD and polyneuropathy indicates shared risks. We suggest that individuals with polyneuropathy routinely undergo screening for CD. There is no notable association between CD and other neurological outcomes investigated in this study.