Allergy and multiple sclerosis: a population-based case-control study

Asthma and chronic obstructive pulmonary disease (COPD) in people with multiple sclerosis: A systematic review and meta-analysis

BACKGROUND

Studies have found that multiple sclerosis (MS) has an impact on the initiation or the course of asthma and chronic obstructive pulmonary disease (COPD). This review amied to investigate the prevalence and odds of asthma and COPD among people with MS (pwMS).

METHOD

PubMed, Embase, Scopus, and Web of Science were systemically searched from inception to May 2023. R version 4.3.2 and random-effect model were used to calculate the pooled prevalence and odds ratio (OR), with their 95 % confidence interval (CI), in pwMS.

RESULTS

A total of 40 studies consisting of 287,702 pwMS were included. 37 studies indicated that the pooled prevalences of asthma and COPD among pwMS were 5.97 % (95 % CI: 4.62 %-7.69 %, I2=99 %) and 3.03 % (95 % CI: 1.82 %-5.00 %, I2=99 %), respectively. 24 studies on 236,469 pwMS and 85,328,673 healthy controls revealed that the overall odds of asthma and COPD in MS were 1.14 (95 % CI: 0.76-1.71, p-value=0.53, I2=97 %) and 1.28 (95 % CI: 1.11-1.47, p-value<0.01, I2=70 %), respectively.

CONCLUSION

MS can increased the risk of developing COPD, while asthma does not exhibit a significant relationship with MS. Our study highlights the importance of identifying pwMS who face greater risks of respiratory issues to monitor efficiently and initiate suitable preventative actions.

Berberine: A natural modulator of immune cells in multiple sclerosis

Berberine is a benzylisoquinoline alkaloid found in such plants as Berberis vulgaris, Berberis aristata, and others, revealing a variety of pharmacological properties as a result of interacting with different cellular and molecular targets. Recent studies have shown the immunomodulatory effects of Berberine which result from its impacts on immune cells and immune response mediators such as diverse T lymphocyte subsets, dendritic cells (DCs), and different inflammatory cytokines. Multiple sclerosis (MS) is a chronic disabling and neurodegenerative disease of the central nervous system (CNS) characterized by the recruitment of autoreactive T cells into the CNS causing demyelination, axonal damage, and oligodendrocyte loss. There have been considerable changes discovered in MS regards to the function and frequency of T cell subsets such as Th1 cells, Th17 cells, Th2 cells, Treg cells, and DCs. In the current research, we reviewed the outcomes of in vitro, experimental, and clinical investigations concerning the modulatory effects that Berberine provides on the function and numbers of T cell subsets and DCs, as well as important cytokines that are involved in MS.

A systematic review of morbidities suggestive of the multiple sclerosis prodrome

INTRODUCTION

The identification of a prodromal phase in multiple sclerosis (MS) could have major implications for earlier recognition and management of MS. The authors conducted a systematic review assessing studies of morbidities before, or at, MS onset or diagnosis.Areas covered: Two independent reviewers searched Medline, Embase, Psycinfo and CINAHL from inception to February 8^th, 2019. To be eligible, studies had to be published in English and report the relative occurrence of at least one morbidity or symptom before, or at, MS onset or diagnosis among MS cases in comparison to a control group not known to have MS. Findings were narratively synthesized. Study quality was assessed using the Newcastle-Ottawa scale (NOS, maximum score 9).Expert opinion: Twenty-nine studies were included, which comprised 83,590 MS cases and 396,343 controls. Most were case-control studies (25/29), 8/29 were of high quality (NOS≥8) and 19/29 examined the period before MS symptom onset. Most studies assessing anxiety, depression, migraine and lower cognitive performance found these conditions to be more prevalent before MS onset or diagnosis relative to controls. There was limited evidence to implicate other conditions. Thus, there is evidence that anxiety, depression, migraine and lower cognitive performance form part of the MS prodrome.

Food allergies are associated with increased disease activity in multiple sclerosis

OBJECTIVE

The association between allergy and multiple sclerosis (MS) is still unclear. In our study, we assessed the association between a self-reported history of allergic conditions with MS clinical and MRI disease activity.

METHODS

A subset of 1349 patients enrolled in the Comprehensive Longitudinal Investigation of Multiple Sclerosis at the Brigham and Women's Hospital (CLIMB) study completed a self-administered questionnaire on environmental, food and drug allergies. Patients were distributed among four allergy groups: (1) environmental, (2) food, (3) drug, (4) no known allergies (NKA). Clinical (number of attacks, expanded disability status scale (EDSS), MS severity score (MSSS)) and radiological variables (presence of gadolinium-enhancing lesions and lesion count), and their associations with the different allergy groups or those with NKA, were assessed.

RESULTS

The food allergy group had a 1.38 times higher rate for cumulative number of attacks compared with the NKA group (P=0.0062); this difference remained significant in the adjusted analysis (relapse rate ratio 1.27, P=0.0305). The food allergy group showed more than twice the likelihood (OR 2.53, P=0.0096) of having gadolinium-enhancing lesions on MRI. The environmental and drug allergy groups did not show significant differences when compared with the NKA group. The EDSS and MSSS were not affected by any type of allergy.

CONCLUSIONS

MS patients with food allergy had more relapses and a higher likelihood of gadolinium-enhancing lesions compared with patients with no known allergy. Future prospective studies are needed to confirm our findings and investigate underlying biological mechanisms, which may unveil new therapeutic and preventative strategies for MS.

Association Between Exposure of Ipratropium and Salmeterol and Diagnosis of Multiple Sclerosis: A Matched Case-control Study

PURPOSE

Ipratropium and salmeterol were found to stimulate oligodendrocyte differentiation in a high-throughput drug screening assay; thus, they may play a role in the risk reduction of multiple sclerosis (MS). So far, they have not been examined in any clinical data. This study aims at investigating the association between ipratropium and salmeterol and reduced diagnosis of MS with the use of real-world clinical data.

METHODS

We conducted a 1:10 matched case-control study that compared the exposure of ipratropium and salmeterol between patients with MS and control patients over the past 2 years, using the MS Flowsheet Registry of OSF HealthCare Saint Francis Medical Center. Cases were matched to control patients, based on service year/quarter, age, sex, race, and payer type. The relationship was examined with a Poisson regression model and a generalized structural equation model.

FINDINGS

The sample in our analysis included 217 patients with MS and 2164 matched control patients. The mean (SD) age for both patients with MS and control patients was 41 (11.8) years with a range of 18 to 75 years. The MS group had consistently less prescriptions of ipratropium and salmeterol than the control group in the past 1, 2, and 3 years before the index date. Our multivariable analysis found that the control group had 3.2 more prescriptions (95% CI, 1.4-7.1; P = 0.006) of either ipratropium or salmeterol in the past 2 years than the MS group, even if controlling for other confounders. In the generalized structural equation model, we found that use of ipratropium and salmeterol was significantly associated with reduced diagnosis of MS (P = 0.036), whereas smokers and people with family history of MS were more likely to have a diagnosis of MS (P < 0.001).

IMPLICATIONS

The observed association between ipratropium and salmeterol use and reduced diagnosis of MS indicates that they might potentially serve as agents in the treatment of MS.

Prevalence of asthma in multiple sclerosis: A United States population-based study

BACKGROUND

Multiple sclerosis (MS) and asthma are complex multifactorial diseases which adversely impact daily functioning. However, the prevalence of asthma in those with MS is not clear. The objective of this study is to characterize the prevalence of asthma in those with MS, with considerations for age, gender, and race.

METHODS

We conducted a U.S. population-based, cross-sectional study of electronic health record information for 56.6 million Americans available in the IBM® Explorys EPM: Explore database. We evaluated the prevalence of asthma in MS (N = 141,880) and non-MS (N = 56,416,790) cohorts, stratifying by age, gender, and race (All, White Americans, and African Americans).

RESULTS

The prevalence of asthma was significantly greater among those with MS than the general population across age, gender, and racial subpopulations. Adjusting for age and gender, asthma was three times more common in MS. In the MS cohort, the prevalence of asthma had a U-shaped distribution with respect to age, with the greatest asthma prevalence among the young and the elderly (> 20% prevalence among those <30 or ≥80 years; prevalence range: 15 to 30%); this significantly differed from the fairly uniform distribution observed in the non-MS cohort (prevalence range: 4 to 9%). These patterns were relatively consistent when stratifying by gender and race.

CONCLUSION

Asthma is significantly more common in those with MS than in the general population - particularly in the young and elderly - irrespective of gender and race. The results add to the growing MS comorbidity literature, and emphasizes the need for comorbidity management as a part of comprehensive MS patient care.

Different Expressions of Specific Transcription Factors of Th1 (T-bet) and Th2 cells (GATA-3) by Peripheral Blood Mononuclear Cells From Patients With Multiple Sclerosis

Introduction:

Multiple Sclerosis (MS) is an inflammatory disorder caused by self-reactive Th1 lymphocytes, while Th2 cells may confer protection. The Th1 and Th2 cell differentiation are regulated by specific transcription factors, especially T-bet and GATA-3, respectively. This investigation aimed to measure the T-bet and GATA-3 expression by Peripheral Blood Mononuclear Cells (PBMCs) obtained from MS patients after specific and non-specific in vitro stimulation.

Methods:

The PBMCs were separated from 22 patients with MS and 20 healthy individuals. They were cultured at 37°C for 24 h in the absence of a stimulator or in the presence of Myelin oligodendrocyte Glycoprotein (MOG) or Phytohemagglutinin (PHA) at a concentration of 10 μg/mL. Then the T-bet and GATA-3 expression was measured by real time-PCR.

Results:

The T-bet expression was enhanced, while the GATA-3 expression diminished. Therefore the expression of T-bet/GATA-3 ratio diminished in not-stimulated, MOG-stimulated and PHA-stimulated PBMCs from MS patients compared with equal cultures from the healthy individuals (P<0.01, P<0.01 and P<0.01, for T-bet; P<0.03, P<0.01 and P<0.02, for GATA-3; P<0.01, P<0.001 and P<0.01 for T-bet/GATA-3 ratio, respectively). The not-stimulated, MOG-stimulated, and PHA-stimulated PBMCs from men with MS expressed higher amounts of GATA-3 than equal cells from MS women (P<0.05, P<0.05 and P<0.01, respectively).

Conclusion:

These results probably indicate an imbalance in Th1/Th2 cells in the level of transcription factors with a tendency toward Th1 cells in MS. The clinical utilization of the transcription factors as novel biomarkers of MS should be evaluated in further studies.

Allergies, antibiotics use, and multiple sclerosis

BACKGROUND

The associations between allergies, antibiotics use, and multiple sclerosis (MS) remain controversial and their mediating or moderating effects have not yet been examined. We aimed to assess the direct and indirect influences of allergies and antibiotics use on MS development, and their interactions.

METHODS

A 1:3 matched case-control study was performed using the National Ambulatory Medical Care Survey database from 2006 to 2013 in the USA. Multiple sclerosis was identified based on the ICD-9 code (340.0) in any position. Cases were matched to their controls based on survey year, age, gender, race, payer type, region, and tobacco use. Allergy diseases and antibiotics prescriptions were extracted by ICD-9 code and drug classification code, respectively. Both generalized structural equation model and MacArthur approach were used to examine their intrinsic relationships.

RESULTS

The weighted prevalence of MS was 133.7 per 100,000 visits. A total of 829 MS patients and 2441 controls were matched. Both respiratory tract allergies (OR = 0.29, 95% CI: 0.18, 0.49) and other allergies (OR = 0.38, 95% CI: 0.19, 0.77) were associated with a reduction of the risk of MS. Patients with respiratory tract allergies were more likely to use penicillin (OR = 8.73, 95% CI: 4.12, 18.53) and other antibiotics (OR = 3.77, 95% CI: 2.72, 5.21), and those with other allergies had a higher likelihood of penicillin use (OR = 4.15, 95% CI: 1.27, 13.54); however, the link between antibiotics use and MS was not confirmed although penicillin use might mediate the relationship between allergies and MS.

CONCLUSIONS

The findings supported allergy as a protective factor for MS development. We also suggest antibiotics use might not be a suitable indicator of bacterial infection to investigate the cause of MS.

Evaluating the association of allergies with multiple sclerosis susceptibility risk and disease activity in a pediatric population

BACKGROUND

Multiple sclerosis (MS) and allergies are both considered to be related to imbalanced Th1 and Th2 immune responses. Previous studies evaluating the relationship between MS and allergies provide conflicting results.

OBJECTIVE

To assess allergies and asthma as risk factors for MS and as predictors of MS relapses in a pediatric cohort.

METHODS

The environment and genetic risk factors for pediatric MS study is a national case-control project with 16 participating US sites. An environmental questionnaire is used that includes history of allergies in the first five years of life. Case-control data are entered in the pediatric MS Network database and cases at 12 of the 16 sites enter relapse data prospectively. Annualized relapse rate was calculated for patients with follow-up and adjusted for age at disease onset, gender, race, ethnicity, and use of disease-modifying therapy (DMT).

RESULTS

We included 271 cases (mean age at disease onset of 15.7years and 62% female) and 418 controls. Relapse data were available for 193 cases. There was no difference in prevalence of allergies or asthma between cases and controls. Patients with food allergies had fewer relapses compared to patients without food allergies (0.14 vs 0.48, p=0.01).

CONCLUSIONS

While allergies and asthma are not associated with pediatric MS, cases with food allergies have fewer relapses compared to those without food allergies.

Inverse comorbidity in multiple sclerosis: Findings in a complete nationwide cohort

BACKGROUND

Inverse comorbidity is disease occurring at lower rates than expected among persons with a given index disease. The objective was to identify inverse comorbidity in MS.

METHODS

We performed a combined case-control and cohort study in a total nationwide cohort of cases with clinical onset of MS 1980-2005. We randomly matched each MS-case with five population controls. Comorbidity data were obtained from multiple, independent nationwide registries. Cases and controls were followed from January 1977 to the index date, and from the index date through December 2012. We controlled for false discovery rate and investigated each of eight pre-specified comorbidity categories: psychiatric, cerebrovascular, cardiovascular, lung, and autoimmune comorbidities, diabetes, cancer, and Parkinson's disease.

RESULTS

A total of 8947 MS-cases and 44,735 controls were eligible for inclusion. We found no inverse associations with MS before the index date. After the index date, we found a decreased occurrence of chronic lung disease (asthma and chronic obstructive pulmonary disease) (HR 0.80 (95% CI 0.75-0.86, p<0.00025)) and overall cancer (HR 0.88 (95% CI 0.81-0.95, p=0.0005)) among MS-cases.

CONCLUSION

This study showed a decreased risk of cancers and pulmonary diseases after onset of MS. Identification of inverse comorbidity and of its underlying mechanisms may provide important new entry points into the understanding of MS.

Risk factors in multiple sclerosis: a population-based case-control study in Sicily. Background and methods

Incidence of multiple sclerosis (MS) has steeply increased over time during the last 30 years in the city of Catania. We carried out a population-based case-control study to evaluate the possible role of both environmental and genetic factors. From 1975 to 2004 in Catania, 367 MS patients diagnosed according to the Poser's criteria had the onset of disease. A sample of MS patients was randomly selected from this incident cohort. Three controls matched by age and sex were randomly selected from the rosters of 14 GPs. Controls were proportionally selected according to the distribution by municipality of the target population using a multistage sampling methods. All cases and controls underwent a face-to-face interview to record information concerning environmental factors and a blood sample was taken for serological and genetic analysis. 164 MS patients (64 % women; mean age of 46.4 ± 10.7) and 481 controls (69 % women; mean age of 47.7 ± 14.8) were enrolled in the study. The distribution of the whole population and the selected controls by municipalities was similar. A blood sample was taken from 150 MS cases and from 337 controls. At the end of the enrolment, we obtained a representative sample of the MS cases and population controls avoiding possible selection bias. Participation rate was very high also concerning the collection of biological specimens.

Factors associated with onset, relapses or progression in multiple sclerosis: A systematic review

Multiple sclerosis (MS) is a chronic disease of the central nervous system with an unidentified etiology. We systematically reviewed the literature on the possible risk factors associated with MS disease onset, relapses and progression from 1960 to 2012 by accessing six databases and including relevant systematic reviews, meta-analyses, case-control or cohort studies. The focus was on identifying modifiable risk factors. Fifteen systematic reviews and 169 original articles were quality assessed and integrated into a descriptive review. Best evidence, which included one or more prospective studies, suggested that lower exposure to sunlight and/or lower serum vitamin D levels were associated with an increased risk of developing MS onset and subsequent relapses, but a similar quality of evidence was lacking for disease progression. Prospective studies indicated that cigarette smoking may increase the risk of MS as well as accelerate disease progression, but whether smoking altered the risk of a relapse was largely unknown. Infections were implicated in both risk of developing MS and relapses, but data for progression were lacking. Specifically, exposure to the Epstein-Barr virus, particularly if this manifested as infectious mononucleosis during adolescence, was associated with increased MS risk. Upper respiratory tract infections were most commonly associated with an increase in relapses. Relapse rates typically dropped during pregnancy, but there was no strong evidence to suggest that pregnancy itself altered the risk of MS or affected long-term progression. Emerging research with the greatest potential to impact public health was the suggestion that obesity during adolescence may increase the risk of MS; if confirmed, this would be of major significance.

Deleterious versus protective autoimmunity in multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory and neurodegenerative disorder of central nervous system, in which myelin specific CD4(+) T cells have a central role in orchestrating pathological events involved in disease pathogenesis. There is compelling evidence that Th1, Th9 and Th17 cells, separately or in cooperation, could mediate deleterious autoimmune response in MS. However, the phenotype differences between Th cell subpopulations initially employed in MS pathogenesis are mainly reflected in the different patterns of inflammation introduction, which results in the development of characteristic pathological features (blood-brain barrier disruption, demyelination and neurodegeneration), clinically presented with MS symptoms. Although, autoimmunity was traditionally seen as deleterious, some studies indicated that autoimmunity mediated by Th2 cells and T regulatory cells could be protective by nature. The concept of protective autoimmunity in MS pathogenesis is still poorly understood, but could be of great importance in better understanding of MS immunology and therefore, creating better therapeutic strategies.

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.

Beta2-adrenergic agonist use and the risk of multiple sclerosis: a total population-based case-control study

OBJECTIVE

The aim of this study was to investigate whether the use of fenoterol, a beta2-adrenergic agonist, was associated with multiple sclerosis (MS) risk by conducting a total population-based case-control study in Taiwan.

METHODS

A total of 578 patients with newly diagnosed MS who had a severely disabling disease (SDD) certificate between January 1, 2002 and December 1, 2008 comprised the case group. These cases were compared with 2890 gender-, age-, residence-, and insurance premium-matched controls. Fenoterol use was analyzed using a conditional logistic regression model that controlled for asthma, chronic obstructive pulmonary disease (COPD), salbutamol and steroid use.

RESULTS

Compared with the group of people who did not use fenoterol, the adjusted odds ratios were 0.67 (95% confidence interval (CI) = 0.48-0.93, p = 0.016) for the group prescribed fenoterol below 2.25 cumulative defined daily dose (cDDD) and 0.49 (95% CI = 0.33-0.71, p < 0.001) for the group with a cumulative fenoterol use of more than 2.25 cDDD. The dose-response relationship was similar within the non-asthma patients. The associations were similar between males and females, but differences between age groups were observed.

CONCLUSIONS

The results of this study suggest that fenoterol use may reduce the risk of MS.

Prevalence of atopic disorders in rheumatic diseases

OBJECTIVES

The aim of this study was to assess the point prevalences of hay fever, asthma, and atopic dermatitis in OA, RA, and AS, and to compare with healthy controls.

METHODS

A total of 935 patients and healthy controls were included. Demographic and clinical features were recorded, and a questionnaire assessing the existence of atopic disorders like asthma, hay fever, and atopic dermatitis in all groups was applied. "Either atopy" implied that an individual was either diagnosed with or had symptoms of one or more of these disorders, such as asthma, hay fever, or atopic dermatitis.

RESULTS

When compared to the controls, only patients with AS had an increased risk for hay fever (OR 1.52, 95 % CI 1.00-2.41). Patients with RA had increased risks for hay fever, atopic dermatitis, and either atopy compared to the patients with OA (2.14, 95 % CI 1.18-3.89; 1.77, 95 % CI 1.00-3.18; and 3.45, 95 % CI 1.10-10.87, respectively). Steroid use had no effect on the prevalence of atopic disorders in patients with RA.

CONCLUSIONS

Patients with OA, RA, and AS seem to have similar risks for asthma, atopic dermatitis, and either atopy to healthy controls. However, the prevalence of hay fever may increase in AS. Patients with RA have a higher risk of atopy than patients with OA.

Comparison of carbamazepine rash in multiple sclerosis and epilepsy

OBJECTIVES

Studies on the comorbidity of multiple sclerosis (MS) and allergic disorders have shown conflicting results. Carbamazepine (CBZ) is widely used in MS to control pain. We have compared the incidence of rash from CBZ use in MS and epilepsy.

MATERIALS AND METHODS

Consecutive adult patients with MS and epilepsy were studied retrospectively. A detailed survey of medical records concerning CBZ treatment was performed.

RESULTS

A total of 495 patients with epilepsy and 442 patients with MS were included. Sixty-five per cent of patients with epilepsy and 20% of patients with MS had used CBZ. In CBZ-exposed patients, rash occurred in 15/89 (17%) in MS and in 43/323 (13%) in epilepsy, a difference which was not significant. Women below 50 years experienced more skin reactions than older women and men. The unadjusted odds ratio (OR) for rash in the MS vs epilepsy group was 1.32 (CI 0.70-2.51, P = 0.40). Adjusting groups for gender and age reduced the OR to 1.11 (CI 0.56-2.19, P = 0.76).

CONCLUSION

Compared with epilepsy, which is only rarely caused by immunological mechanisms, the autoimmune disorder MS was not associated with a different occurrence of CBZ skin reactions. The trend towards an increased occurrence of rashes in MS can partly be explained by a higher predisposition to CBZ rash in women of fertile age.

Micro-RNA dysregulation in multiple sclerosis favours pro-inflammatory T-cell-mediated autoimmunity

Pro-inflammatory T cells mediate autoimmune demyelination in multiple sclerosis. However, the factors driving their development and multiple sclerosis susceptibility are incompletely understood. We investigated how micro-RNAs, newly described as post-transcriptional regulators of gene expression, contribute to pathogenic T-cell differentiation in multiple sclerosis. miR-128 and miR-27b were increased in naïve and miR-340 in memory CD4(+) T cells from patients with multiple sclerosis, inhibiting Th2 cell development and favouring pro-inflammatory Th1 responses. These effects were mediated by direct suppression of B lymphoma Mo-MLV insertion region 1 homolog (BMI1) and interleukin-4 (IL4) expression, resulting in decreased GATA3 levels, and a Th2 to Th1 cytokine shift. Gain-of-function experiments with these micro-RNAs enhanced the encephalitogenic potential of myelin-specific T cells in experimental autoimmune encephalomyelitis. In addition, treatment of multiple sclerosis patient T cells with oligonucleotide micro-RNA inhibitors led to the restoration of Th2 responses. These data illustrate the biological significance and therapeutic potential of these micro-RNAs in regulating T-cell phenotypes in multiple sclerosis.

Environmental factors in early childhood are associated with multiple sclerosis: a case-control study

BACKGROUND

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS) with increasing incidence mainly in high-income countries. One explanation of this phenomenon may be a higher prevalence of allergic and autoimmune diseases in industrialized countries as a consequence of otherwise beneficial advances in sanitation (hygiene hypothesis). We investigated environmental factors in early childhood associated with MS.

METHODS

A case-control study was performed of 245 MS patients and 296 population-based controls in Berlin. The study participants completed a standardized questionnaire on environmental factors in childhood and youth, including aspects of personal and community hygiene. Multivariable logistic regression analysis was performed to investigate factors in childhood and youth associated with the occurrence of MS.

RESULTS

Mean age was 46 years (range, 20-80) in the MS group and 42 years (range 18-80) in the control group, of which 73.9% in the MS and 61.5% in the control group were female. The multivariable analysis showed that having at least two older siblings (OR 0.54; p = 0.05, for individuals with two older siblings compared to individuals without older siblings), attending a day-care center (OR 0.5; p = 0.004) and growing up in an urban center with more than 100, 000 inhabitants (OR 0.43; p = 0.009) were factors independently associated with a lower chance for MS.

CONCLUSIONS

The hygiene hypothesis may play a role in the occurrence of MS and could explain disease distribution and increasing incidence.

The ‘hygiene hypothesis’ and the development of multiple sclerosis

SUMMARY We review evidence linking inadequate microbial exposure in early life to the development of multiple sclerosis (MS). There is some supportive, but not conclusive evidence for a role of a hygienic environment in early life and MS. Population-level studies of MS are consistent with the hygiene hypothesis but are limited by methodological issues. Late infection with Epstein–Barr virus (EBV) has been prospectively associated with MS and must be incorporated into any model where the hygiene hypothesis is implicated in the development of MS. One possibility is that inadequate microbial exposure in early life contributes to a dysregulated host immune response to EBV. Two areas of particular interest include the potential role for helminthic infection in biasing the human immune response away from the immune profile associated with MS and also the role of microbial exposure in training the development of the EBV-specific immune response.

The effect of Kawasaki disease on childhood allergies - a sibling control study

OBJECTIVE

Kawasaki disease (KD) is a multisystem inflammatory vasculitis of childhood, with widespread T-helper cell type 1 immune activation. We hypothesize that children who suffered from KD will have a lower risk of developing allergic diseases.

STUDY DESIGN

This was a cross-sectional study, recruiting children with a history of KD, together with well sibling controls. All children underwent the standardized core ISAAC questionnaire for allergy, physical examination and skin prick test evaluation. McNemar's test was employed to evaluate the effect of Kawasaki disease on allergy. Multivariable analysis based on mixed-effects logistic regression model was used to adjust for potential confounding effect of age and gender.

RESULTS

One hundred and eighty-six children (93 KD sibling pairs) completed the above evaluation. Allergic rhinitis was more common in patients with KD (crude OR 2.40; 95% CI 1.11-5.62, p=0.024) when compared with controls. The effect was further intensified after accounting for the potential confounding effect of age and gender (adjusted OR=2.90; 95% CI 1.27-6.60). Children in whom KD occurred beyond the age of 12 months had more allergic rhinitis (crude OR 4.00, 95% CI 1.29-16.44, p=0.012), 'any' allergies (crude OR 3.75, 95% CI 1.19-15.52, p=0.019) and Blomia tropicalis sensitization (crude OR 2.57, 95% CI 1.02-7.28, p=0.043) when compared with their sibling controls. Interestingly, children in whom KD course resulted in no coronary artery abnormalities have more allergic rhinitis (crude OR 8.50, 95% CI 2.02-75.85, p=0.003) and 'any' allergies (crude OR 5.00, 95% CI 1.41-26.94, p=0.011), when compared with their sibling controls.

CONCLUSION

Kawasaki disease may be a risk factor for subsequent allergic diseases. We postulate that KD occurs more frequently in children at risk of immune disequilibrium, with an abnormal inflammatory response initially, and subsequently more allergic manifestations.

Association between allergies and multiple sclerosis: a systematic review and meta-analysis

Multiple sclerosis (MS) is an inflammatory disease of the central nervous system that expresses a typical type 1 immune response (Th1). Allergies, on the other hand, present with high levels of type 2 (Th2) cytokines. Some authors observed that Th1 and Th2 diseases could coexist in the same subject. Besides its biological plausibility, the association between MS and allergies remains controversial. The aim of this systematic review and meta-analysis was to determine if there is an association between allergic diseases and MS. All clinical and epidemiological studies on patients with MS published up to July 2009, that assessed the association between allergic diseases and MS were reviewed. A total of 1010 articles were retrieved from search, and ten epidemiological studies were included in the analysis. The results showed that there is no evidence supporting an association between allergic diseases (OR: 0.91; CI 95%: 0.68-1.23), asthma (OR: 0.83; CI 95%: 0.48-1.44), allergic rhinitis (OR: 0.81; CI 95%: 0.59-1.12), eczema (OR: 0.93; CI 95%: 0.71-1.23) and MS. Additional prospective studies in this field might help to elucidate the nature of these associations.