Obesity during childhood and adolescence increases susceptibility to multiple sclerosis after accounting for established genetic and environmental risk factors

Metformin as a therapeutic agent for obesity-associated immune dysfunction

Obesity is associated with impaired immune function, characterized by inflammation, and leading to poor response to infection, impaired vaccine response, increased susceptibility to autoimmune disease, and increased risk of cancer and cancer mortality. Worse, there is evidence that weight loss alone may be insufficient to reverse the immune dysfunction caused by obesity. It is therefore critically important to identify alternative therapeutic approaches to decrease the negative effects of obesity-associated inflammation. Here, we will review evidence that the antidiabetic drug metformin may be considered as a therapeutic agent for obesity-associated immune dysfunction. Metformin has immune-modulatory effects, stimulating or suppressing the immune response in both a cell-specific and disease-specific manner. Although the mechanism of action of metformin on the immune system remains to be fully elucidated, there is strong evidence that metformin enters select immune cells and disrupts electron transport, leading to both AMPK-dependent and AMPK-independent effects on immune cell differentiation and cytokine production. These effects of metformin on immune cells have been shown to improve immune responses to infection, autoimmunity, and cancer.

From progression to progress: The future of multiple sclerosis

Significant advances have been made in the diagnosis and treatment of multiple sclerosis in recent years yet challenges remain. The current classification of MS phenotypes according to disease activity and progression, for example, does not adequately reflect the underlying pathophysiological mechanisms that may be acting in an individual with MS at different time points. Thus, there is a need for clinicians to transition to a management approach based on the underlying pathophysiological mechanisms that drive disability in MS. A Canadian expert panel convened in January 2023 to discuss priorities for clinical discovery and scientific exploration that would help advance the field. Five key areas of focus included: identifying a mechanism-based disease classification system; developing biomarkers (imaging, fluid, digital) to identify pathologic processes; implementing a data-driven approach to integrate genetic/environmental risk factors, clinical findings, imaging and biomarker data, and patient-reported outcomes to better characterize the many factors associated with disability progression; utilizing precision-based treatment strategies to target different disease processes; and potentially preventing disease through Epstein-Barr virus (EBV) vaccination, counselling about environmental risk factors (e.g. obesity, exercise, vitamin D/sun exposure, smoking) and other measures. Many of the tools needed to meet these needs are currently available. Further work is required to validate emerging biomarkers and tailor treatment strategies to the needs of individual patients. The hope is that a more complete view of the individual's pathobiology will enable clinicians to usher in an era of truly personalized medicine, in which more informed treatment decisions throughout the disease course achieve better long-term outcomes.

The association between weight during early life and multiple sclerosis onset in a nationwide Dutch birth year cohort

BACKGROUND

The relationship between being overweight during early life and disease course in multiple sclerosis (MS) is unresolved. We investigated the association between being overweight or obese during early life (childhood and adolescence) and MS case status, age of first symptom onset and onset type in people with MS (pwMS) of the same birth year.

METHODS

We enrolled 363 PwMS and 125 healthy controls (HC) from Project Y, a Dutch population-based cross-sectional cohort study including all PwMS born in 1966 and age and sex-matched HC. The associations between weight during childhood and adolescence (non-overweight vs. overweight or obese) and MS, age at symptom onset and onset type (relapsing vs. progressive) were assessed using logistic and linear regressions. In addition, sex-separated associations were explored.

RESULTS

Being overweight or obese during childhood (OR = 2.82, 95% CI 1.17-6.80) and adolescence (OR = 2.45, 95% CI 1.13-5.34) was associated with developing MS. Furthermore, being overweight or obese during adolescence was associated with a younger age of onset (β = -0.11, p = 0.041). Of all 47 patients with a primary progressive (PP) onset type, only one patient (2.1%) was overweight or obese during childhood, whereas 45 patients with a relapsing remitting (RR) onset (14.3%) were overweight or obese during childhood (PP vs. RR p = 0.017; PP vs. HC p = 0.676; RR vs. HC, p = 0.015). However, using logistic regression analysis we did not find evidence of a significant association.

CONCLUSION

In a nationwide population-based birth year cohort, being overweight or obese during childhood or adolescence is associated with MS prevalence and an earlier age of onset, but does not seem to associate with the type of onset.

Childhood and adolescence factors and multiple sclerosis: results from the German National Cohort (NAKO)

BACKGROUND

Multiple Sclerosis (MS) represents the most common inflammatory neurological disease causing disability in early adulthood. Childhood and adolescence factors might be of relevance in the development of MS. We aimed to investigate the association between various factors (e.g., prematurity, breastfeeding, daycare attendance, weight history) and MS risk.

METHODS

Data from the baseline assessment of the German National Cohort (NAKO) were used to calculate adjusted hazard ratios (HR) and 95% confidence intervals (CI) for the association between childhood and adolescence factors and risk of MS. Analyses stratified by sex were conducted.

RESULTS

Among a total of 204,273 participants, 858 reported an MS diagnosis. Male sex was associated with a decreased MS risk (HR 0.48; 95% CI 0.41-0.56), while overweight (HR 2.03; 95% CI 1.41-2.94) and obesity (HR 1.89; 95% CI 1.02-3.48) at 18 years of age compared to normal weight were associated with increased MS risk. Having been breastfed for ≤ 4 months was associated with a decreased MS risk in men (HR 0.59; 95% CI 0.40-0.86) compared to no breastfeeding. No association with MS risk was observed for the remaining factors.

CONCLUSIONS

Apart from overweight and obesity at the age of 18 years, we did not observe considerable associations with MS risk. The proportion of cases that can be explained by childhood and adolescence factors examined in this study was low. Further investigations of the association between the onset of overweight and obesity in childhood and adolescence and its interaction with physical activity and MS risk seem worthwhile.

Multiple sclerosis prevalence and its relationship with economic status in Afyonkarahisar, Turkey

BACKGROUND

Over the past decade, the prevalence of Multiple Sclerosis (MS) has increased in Turkey. However, the prevalence of MS in Middle Anatolia, specifically Afyonkarahisar, remains unknown. Additionally, the potential link between economic status and MS has not yet been explored in Turkey.

METHODS

A stratified sampling method was employed to select samples from the population residing in Afyonkarahisar City Center, taking into account demographic factors such as income level, sex, and age. The sample size was calculated using the formula N = p.q.Zα2/d2, where an average prevalence rate of 70/100,000 was considered based on previous studies. The minimum sample size was 29,858. Considering incomplete, inaccurate, and low-reliability data, data were collected from 30,500 individuals and 30,408 individuals were evaluated.

RESULTS

The prevalence of Multiple Sclerosis in the center of Afyonkarahisar was 105.2 per 100,000 individuals. Upon investigating the association between economic status and MS prevalence, the findings revealed rates of 193.6 per 100,000 in individuals with high income, contrasting with 80.2 per 100,000 in those with low income. Notably, a heightened prevalence of MS is evident among individuals with higher income levels.

CONCLUSION

This study revealed a significantly elevated prevalence of MS in Afyonkarahisar, the highest in Turkey. The inverse correlation between the prevalence of MS and socioeconomic status is intriguing. Possible reasons for the high prevalence include the relatively new and specific geologic and environmental conditions in the area.

Pediatric Onset Multiple Sclerosis and Obesity: Defining the Silhouette of Disease Features in Overweight Patients

Obesity has been suggested as an environmental risk factor for multiple sclerosis (MS) and may negatively effect the progression of the disease. The aim of this study is to determine any correlation between overweight/obesity and the clinical and neuroradiological features at the onset of pediatric onset multiple sclerosis (POMS). Were included patients referred to the POMS Unit of the Bambino Gesù Children's Hospital between June 2012 and June 2021. The diagnosis of MS with an onset of less than 18 years was required. For all included subjects, we considered for the analysis the following data at the onset of symptoms: general data (age, sex, functional system compromised by neurological signs, weight and height), brain and spinal magnetic resonance imaging (MRI), cerebrospinal fluid exams. We identified 55 pediatric cases of POMS and divided them into two groups according to the body mass index (BMI): 60% were healthy weight (HW) and 40% were overweight/obese (OW/O). OW/O patients experienced a two-year age difference in disease onset compared to the HW patients (12.7 ± 3.8 years vs. 14.6 ± 4.1 years; p < 0.05). Onset of polyfocal symptoms was seen more frequently in OW/O patients than in HW (72.7% vs. 21.2%; p < 0.05). The pyramidal functions were involved more frequently in the OW/O group than in the HW group (50% vs. 25%; p < 0.005). Black holes were detected more frequently in OW/O patients in onset MRI scans compared to the HW group (50% vs. 15.5%; p < 0.05). Our findings suggest that being overweight/obese affects the risk of developing MS at an earlier age and is associated with an unfavorable clinical-radiological features at onset. Weight control can be considered as a preventive/therapeutic treatment.

Characterizing causal relationships of visceral fat and body shape on multiple sclerosis risk

BACKGROUND

Epidemiologic studies have established obesity as a risk factor for multiple sclerosis (MS). These studies relied on body-mass index (BMI) and body size silhouettes as the primary measures of obesity. Unfortunately, the causal mechanisms through which obesity confers MS risk are not yet known.

OBJECTIVES

To investigate the causal effects of multiple specific measures of body fat on MS risk in populations of European descent, using Mendelian randomization (MR).

METHODS

MR is a genetic instrumental variable analysis utilizing genome-wide association (GWA) summary statistics to infer causality between phenotypes. MR analyses were performed to investigate the relationships between seven measures of body fat (BMI, waist-hip ratio, visceral adipose tissue [VAT], subcutaneous adipose tissue, and arm-, leg-, and trunk-fat to total body fat ratio) and MS risk.

RESULTS

Only BMI and VAT were significantly associated with MS risk in separate MR analyses (βBMI=0.27, pBMI<0.001; βVAT=0.28, pVAT=0.006). High correlation between BMI and VAT instruments suggest that two-sample MR associations for BMI and VAT likely capture the same causal mechanisms.

CONCLUSIONS

BMI and VAT were causally associated with MS risk in European populations, though their effects do not appear independent, suggesting overlap in the role of overall body mass and visceral obesity in MS pathogenesis.

Vascular multiple sclerosis: addressing the pathogenesis, genetics, pro-angiogenic factors, and vascular abnormalities, along with the role of vascular intervention

Dysfunction in the epithelium, breakdown of the blood-brain barrier, and consequent leukocyte and T-cell infiltration into the central nervous system define Vascular Multiple Sclerosis. Multiple sclerosis (MS) affects around 2.5 million individuals worldwide, is the leading cause of neurological impairment in young adults, and can have a variety of progressions and consequences. Despite significant discoveries in immunology and molecular biology, the root cause of MS is still not fully understood, as do the immunological triggers and causative pathways. Recent research into vascular anomalies associated with MS suggests that a vascular component may be pivotal to the etiology of MS, and there can be actually a completely new entity in the already available classification of MS, which can be called 'vascular multiple sclerosis'. Unlike the usual other causes of MS, vascular MS is not dependent on autoimmune pathophysiologic mechanisms, instead, it is caused due to the blood vessels pathology. This review aims to thoroughly analyze existing information and updates about the scattered available findings of genetics, pro-angiogenetic factors, and vascular abnormalities in this important spectrum, the vascular facets of MS.

Demographic and Clinical Predictors of Disease Severity in Patients With Multiple Sclerosis: A Retrospective Cross-Sectional Analysis

OBJECTIVES

Multiple sclerosis (MS) is a disease of the central nervous system (CNS). Several factors, including sex, body mass index (BMI), disease duration, and age of onset, have been identified as predictors of disease severity. This study investigated the association between the aforementioned factors and MS severity, measured by the number of hospital visits and admissions, length of stay, and frequency of methylprednisolone use.

METHODS

This retrospective cross-sectional analysis used data obtained from BESTCare at the King Abdulaziz Medical City (KAMC). A total of 272 patients with MS and their demographic and clinical characteristics were included.

RESULTS

The study population consisted of 68.75% (n = 187) females and 31.25% (n = 85) males. The regression analyses indicated that disease duration was a significant predictor of the number of hospital visits and admissions (p < 0.01). The study found a significant association between BMI (unstandardized beta (B) = -0.25, 95% confidence interval (CI) = -0.47, -0.02, p = 0.033), age at diagnosis (unstandardized beta (B) = 0.15, 95% CI = 0.001, 0.31, p = 0.048), and length of hospital stay. Additionally, there was a significant correlation between disease duration and the number of methylprednisolone doses (unstandardized beta (B) = 0.45, 95% CI = 0.01, 0.89, p = 0.045).

CONCLUSION

Disease duration was found to be a significant predictor of hospital visits, admissions, and methylprednisolone use, while sex and BMI did not contribute to the variation in these outcomes. However, BMI and age of onset were significantly associated with length of hospital stay.

The role of diet in multiple sclerosis onset and course: results from a nationwide retrospective birth-year cohort

OBJECTIVE

To examine (1) the association between childhood diet and developing MS, age of onset and onset type and (2) the association between diet at age 50 and disability and MRI volumes in people with MS (PwMS).

METHODS

The study enrolled 361 PwMS born in 1966 and 125 age- and sex-matched healthy controls (HCs). Information on individual dietary components (fruit, vegetables, red meat, oily fish, whole-grain bread and candy, snacks and fast food) and MS risk factors at the age of 10 and 50 years were collected using questionnaires. Overall diet quality score was calculated for each participant. Multivariable regression analyses were used to evaluate the association between diet at childhood and developing MS, age of onset and onset type and to evaluate diet at age 50, disability and MRI outcomes.

RESULTS

Poorer overall diet quality and individual dietary components during childhood (less whole-grain bread, more candy, snacks and fast food and oily fish) were associated with developing MS and onset type (all p < 0.05), but not with the age of onset. Fruit consumption at age 50 was associated with lower disability (Q3 vs. Q1: -0.51; 95% CI: -0.89 to -0.13). Furthermore, several individual dietary components at age 50 were associated with MRI volumetric measures. Higher-diet quality at age 50 was only associated with lower lesion volumes in PwMS (Q2 vs. Q1: -0.3 mL; 95% CI: -0.5 to -0.02).

INTERPRETATION

We demonstrate significant associations between dietary factors in childhood and developing MS, age of onset and onset type and between dietary factors at age 50 and disability and MRI-derived volumes.

Dietary Patterns and Their Associations with Symptom Levels Among People with Multiple Sclerosis: A Real-World Digital Study

INTRODUCTION

The objective of the study was to investigate long-term food intake patterns and establish possible associations between the inferred dietary habits and levels of reported symptoms among people with multiple sclerosis (MS) in Denmark.

METHODS

The present study was designed as a prospective cohort study. Participants were invited to register daily food intake and MS symptoms and were observed during a period of 100 days. Dropout and inclusion probabilities were addressed using generalized linear models. Dietary clusters were identified among 163 participants using hierarchical clustering on principal component scores. Associations between the dietary clusters and the levels of self-assessed MS symptoms were estimated using inverse probability weighting. Furthermore, the effect of a person's position on the first and second principal dietary component axis on symptom burden was investigated.

RESULTS

Three dietary clusters were identified: a Western dietary cluster, a plant-rich dietary cluster and a varied dietary cluster. Analyses further indicated a vegetables-fish-fruit-whole grain axis and a red-meat-processed-meat axis. The plant-rich dietary cluster showed reduction in symptom burden in nine pre-defined MS symptoms compared to the Western dietary cluster (between 19 and 90% reduction). This reduction was significant for pain and bladder dysfunction as well as across all nine symptoms (pooled p value = 0.012). Related to the two dietary axes, high intake of vegetables resulted in 32-74% reduction in symptom burden compared to low levels of vegetable intake. Across symptoms, this was significant (pooled p value = 0.015), also regarding walking difficulty and fatigue.

CONCLUSIONS

Three dietary clusters were identified. Compared to levels of self-assessed MS-related symptoms, and adjusted for potential confounders, the results suggested less symptom burden with increased intake of vegetables. Although the research design limits the possibilities of establishing causal inference, the results indicate that general guidelines for healthy diet may be relevant as a tool in coping with MS symptoms.

Association of adverse childhood experiences with adulthood multiple sclerosis: A systematic review of observational studies

INTRODUCTION

Adverse childhood experiences (ACEs) are proposed to increase the risk of developing multiple sclerosis (MS) later in life. This systematic review aimed to explore the correlation between ACEs and MS development, age of onset, quality of life in MS patients and MS relapse rates.

METHODS

We searched a total of six databases in June 2022 and retrieved the relevant studies. The population included adult (18+) individuals who either had been diagnosed or were at risk for developing MS and also had exposure to ACEs. Our primary outcomes include the risks of MS development, age of MS onset, and MS relapse rate in patients who were exposed to different types of ACEs.

RESULTS

A total of 11 studies were included in our review. A study reported that among 300 women diagnosed with MS, 71 (24%) reported a history of childhood abuse; moreover, with further research, it was concluded that ACEs were associated with the development of MS. Abuse that occurred 2-3 times per week was associated with an 18.81-fold increased risk of having MS when compared to the unexposed sample. The relapse rate of MS was found to be substantially greater in severe cases of ACEs compared to individuals who did not report any ACEs.

CONCLUSIONS

Results support a significant association between ACEs and the development of MS; individuals with a positive history of ACEs develop MS symptoms earlier. Moreover, the severity of ACEs is also linked with increased relapse rates of MS.

Obesity, gut microbiota, and multiple sclerosis: Unraveling the connection

Obesity is associated with chronic mild-grade systemic inflammation and neuroinflammation. Obesity in early childhood and adolescence is also a significant risk factor for multiple sclerosis (MS) development. However, the underlying mechanisms that explain the link between obesity and MS development are not fully explored. An increasing number of studies call attention to the importance of gut microbiota as a leading environmental risk factor mediating inflammatory central nervous system demyelination, particularly in MS. Obesity and high-calorie diet are also associated with disturbances in gut microbiota. Therefore, gut microbiota alteration is a plausible connection between obesity and the increased risk of MS development. A greater understanding of this connection could provide additional therapeutic opportunities, like dietary interventions, microbiota-derived products, and exogenous antibiotics and probiotics. This review summarizes the current evidence regarding the relationships between MS, obesity, and gut microbiota. We discuss gut microbiota as a potential link between obesity and increased risk for MS. Additional experimental studies and controlled clinical trials targeting gut microbiota are warranted to unravel the possible causal relationship between obesity and increased risk of MS.

The State of the Art of Pediatric Multiple Sclerosis

Multiple sclerosis (MS) represents a chronic immune-mediated neurodegenerative disease of the central nervous system that generally debuts around the age of 20-30 years. Still, in recent years, MS has been increasingly recognized among the pediatric population, being characterized by several peculiar features compared to adult-onset disease. Unfortunately, the etiology and disease mechanisms are poorly understood, rendering the already limited MS treatment options with uncertain efficacy and safety in pediatric patients. Thus, this review aims to shed some light on the progress in MS therapeutic strategies specifically addressed to children and adolescents. In this regard, the present paper briefly discusses the etiology, risk factors, comorbidities, and diagnosis possibilities for pediatric-onset MS (POMS), further moving to a detailed presentation of current treatment strategies, recent clinical trials, and emerging alternatives. Particularly, promising care solutions are indicated, including new treatment formulations, stem cell therapies, and cognitive training methods.

Adipokines in multiple sclerosis patients are related to clinical and radiological measures

BACKGROUND

An imbalance of adipokines, hormones secreted by white adipose tissue, is suggested to play a role in the immunopathology of multiple sclerosis (MS). In people with MS (PwMS) of the same age, we aimed to determine whether the adipokines adiponectin, leptin, and resistin are associated with MS disease severity. Furthermore, we aimed to investigate whether these adipokines mediate the association between body mass index (BMI) and MS disease severity.

METHODS

Adiponectin, resistin, and leptin were determined in serum using ELISA. 288 PwMS and 125 healthy controls (HC) were included from the Project Y cohort, a population-based cross-sectional study of people with MS born in the Netherlands in 1966, and age and sex-matched HC. Adipokine levels and BMI were related to demographic, clinical and disability measures, and MRI-based brain volumes.

RESULTS

Adiponectin levels were 1.2 fold higher in PwMS vs. HC, especially in secondary progressive MS. Furthermore, we found a sex-specific increase in adiponectin levels in primary progressive (PP) male patients compared to male controls. Leptin and resistin levels did not differ between PwMS and HC, however, leptin levels were associated with higher disability (EDSS) and resistin strongly related to brain volumes in progressive patients, especially in several grey matter regions in PPMS. Importantly, correction for BMI did not significantly change the results.

CONCLUSION

In PwMS of the same age, we found associations between adipokines (adiponectin, leptin, and resistin) and a range of clinical and radiological metrics. These associations were independent of BMI, indicating distinct mechanisms.

Obesity increases blood-brain barrier permeability and aggravates the mouse model of multiple sclerosis

Obesity-induced insulin resistance (OIR) has been associated with an increased prevalence of neurodegenerative disorders such as multiple sclerosis. Obesity results in increased blood-brain barrier (BBB) permeability, specifically in the hypothalamic regions associated with the control of caloric intake. In obesity, the chronic state of low-grade inflammation has been implicated in several chronic autoimmune inflammatory disorders. However, the mechanisms that connect the inflammatory profile of obesity with the severity of experimental autoimmune encephalomyelitis (EAE) are poorly defined. In this study, we show that obese mice are more susceptible to EAE, presenting a worse clinical score with more severe pathological changes in the spinal cord when compared with control mice. Analysis of immune infiltrates at the peak of the disease shows that high-fat diet (HFD)- and control (chow)-fed groups do not present any difference in innate or adaptive immune cell compartments, indicating the increased severity occurs prior to disease onset. In the setting of worsening EAE in HFD-fed mice, we observed spinal cord lesions in myelinated regions and (blood brain barrier) BBB disruption. We also found higher levels of pro-inflammatory monocytes, macrophages, and IFN-γ⁺CD4⁺ T cells in the HFD-fed group compared to chow-fed animals. Altogether, our results indicate that OIR promotes BBB disruption, allowing the infiltration of monocytes/macrophages and activation of resident microglia, ultimately promoting CNS inflammation and exacerbation of EAE.

Internal comorbidities and complications of multiple sclerosis therapy - don't be caught off guard!

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system, mainly affecting young adults. Factors positively influencing its course include early antiinflammatory treatment and the influencing of other comorbidities. The most common comorbidities occurring in MS patients with a higher frequency than in the general population are neurological, psychiatric, cardiovascular, metabolic and autoimmune. Just as comorbidity compensation affects the course of MS, in some cases, MS decompensation is associated with a worse course of associated diseases. Due to common risk factors and partially shared immunopathogenesis, treatment covering multiple conditions can be used, especially for some autoimmune diseases. On the other hand, some drugs may potentiate the development of other autoimmunity or disorder. A special topic is the side effects and complications of treatment (especially infections and malignancies) of disease-modifying therapies used in patients with MS. However, the potential treatment discontinuation carries significant risks and should always be discussed with the MS specialist. Therefore, close interdisciplinary collaboration is crucial.

Toward Precision Phenotyping of Multiple Sclerosis

The classification of multiple sclerosis (MS) has been established by Lublin in 1996 and revised in 2013. The revision includes clinically isolated syndrome, relapsing-remitting, primary progressive and secondary progressive MS, and has added activity (i.e., formation of white matter lesions or clinical relapses) as a qualifier. This allows for the distinction between active and nonactive progression, which has been shown to be of clinical importance. We propose that a logical extension of this classification is the incorporation of additional key pathological processes, such as chronic perilesional inflammation, neuroaxonal degeneration, and remyelination. This will distinguish MS phenotypes that may present as clinically identical but are driven by different combinations of pathological processes. A more precise description of MS phenotypes will improve prognostication and personalized care as well as clinical trial design. Thus, our proposal provides an expanded framework for conceptualizing MS and for guiding development of biomarkers for monitoring activity along the main pathological axes in MS.

Preventing Multiple Sclerosis: The Pediatric Perspective

Pediatric-onset multiple sclerosis (MS) is a predominantly relapsing-remitting neuroinflammatory disorder characterized by frequent relapses and high magnetic resonance imaging (MRI) lesion burden early in the disease course. Current treatment for pediatric MS relies on early initiation of disease-modifying therapies designed to prevent relapses and slow progression of disability. When considering the concept of MS prevention, one can conceptualize primary prevention (population- or at-risk population interventions that prevent the earliest facet of MS pathobiology and hence reduce disease incidence), or secondary prevention (prevention of disease consequence, such as reducing relapse frequency and lesion accrual, enhancing focal lesion repair, promoting CNS resilience against the more global facets of disease injury, and ultimately, preventing progression of neurological disability). Studying the pediatric MS population provides a unique opportunity to explore early-life exposures that contribute to the development of MS including perinatal and environmental risk determinants. Research is ongoing related to targeting these risk factors for potential MS primary prevention. Here we review these key risk factors, their proposed role in the pathogenesis of MS, and their potential implications for primary MS prevention.

Sex-Specific Environmental Impacts on Initiation and Progression of Multiple Sclerosis

The immunological mechanisms that contribute to multiple sclerosis (MS) differ between males and females. Females are 2–3 times more likely to develop MS compared to males, however the reason for this discrepancy is unknown. Once MS is established, there is a more inflammatory yet milder form of disease in females whereas males generally suffer from more severe disease and faster progression, neural degradation, and disability. Some of these differences relate to genetics, including genetic control of immune regulatory genes on the X-chromosome, as well as immune modulatory properties of sex hormones. Differences in MS development may also relate to how sex interacts with environmental risk factors. There are several environmental risk factors for MS including late-onset Epstein Barr virus infection, low serum vitamin D levels, low UV radiation exposure, smoking, obesity, and lack of physical activity. Most of these risk factors impact males and females differently, either due to biological or immunological processes or through behavioral differences. In this review, we explore these differences further and focus on how the interaction of environmental risk factors with sex hormones may contribute to significantly different prevalence and pathology of MS in males and females.

Effects of dietary restriction on gut microbiota and CNS autoimmunity

Multiple sclerosis (MS) is the most common central nervous system (CNS) autoimmune disease. It is due to the interplay of genetic and environmental factors. Current opinion is that diet could play a pathogenic role in disease onset and development. Dietary restriction (DR) without malnutrition markedly improves health and increases lifespan in multiple model organisms. DR regimens that utilize continuous or intermittent food restriction can induce anti-inflammatory, immuno-modulatory and neuroendocrine adaptations promoting health. These adaptations exert neuroprotective effects in the main MS animal model, experimental autoimmune encephalomyelitis (EAE). This review summarizes the current knowledge on DR-induced changes in gut microbial composition and metabolite production and its impact on underlying functional mechanisms. Studies demonstrating the protective effects of DR regimens on EAE and people with MS are also presented. This is a rapidly developing research field with important clinical implications for personalized dietary interventions in MS prevention and treatment.

Physical and Mental Health Comorbidities Among Adults With Multiple Sclerosis

OBJECTIVE

To compare the incidence of and adjusted hazard ratios for common cardiometabolic diseases, musculoskeletal disorders, and psychological morbidities among adults with and without multiple sclerosis (MS).

PATIENTS AND METHODS

Beneficiaries were included if they had an International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic code for MS (n=9815) from a national private insurance claims database (Clinformatics Data Mart; OptumInsight). Adults without MS were also included (n=1,474,232) as a control group. Incidence estimates of common cardiometabolic diseases, musculoskeletal disorders, and psychological morbidities were compared at 5 years of continuous enrollment. Survival models were used to quantify unadjusted and adjusted hazard ratios for incident morbidities.

RESULTS

Adults with MS had a higher incidence of any common cardiometabolic disease (51.6% [2663 of 5164] vs 36.4% [328,690 of 904,227]), musculoskeletal disorder (68.8% [3411 of 4959] vs 47.5% [512,422 of 1,077,737]), and psychological morbidity (49.4% [3305 of 6691] vs 30.8% [380,893 of 1,235,388]) than adults without MS, and differences were clinically meaningful (all P<.001). Fully adjusted survival models revealed that adults with MS had a greater risk for any (hazard ratio [HR], 1.37; 95% CI, 1.32 to 1.43) and all (HR, 1.19 to 1.48) common cardiometabolic diseases, any (HR, 1.59; 95% CI, 1.53 to 1.64) and all (HR, 1.22 to 2.77) musculoskeletal disorders, and any (HR, 1.57; 95% CI, 1.51 to 1.62) and all (HR, 1.20 to 2.51) but one (impulse control disorders) psychological morbidity.

CONCLUSION

Adults with MS have a significantly higher risk for development of common cardiometabolic diseases, musculoskeletal disorders, and psychological morbidities (all P<.001) than adults without MS. Efforts are needed to facilitate the development of improved clinical screening algorithms and early interventions to reduce risk of chronic physical and mental disease onset/progression in this higher risk population.

Dietary restriction in multiple sclerosis: evidence from preclinical and clinical studies

Dietary restriction (DR) interventions, which encompass both chronic and intermittent reductions in energy intake, are emerging as potential therapeutic approaches for dampening neuroinflammation and demyelination in multiple sclerosis (MS). Mechanisms mediating the beneficial effects of DR include the regulation of pro- and anti-inflammatory signalling molecules and gut microbiome remodelling. This article summarises the preclinical evidence supporting the role of DR in attenuating disease in animal models of MS and the developing clinical evidence indicating the safety and feasibility of such DR interventions in people with MS (pwMS).

Association of Body Mass Index in Adolescence and Young Adulthood and Long-term Risk of Multiple Sclerosis: A Population-Based Study

BACKGROUND AND OBJECTIVES

To prospectively investigate the long-term relationship between body mass index (BMI) in adolescents and young adults and risk for multiple sclerosis (MS) at the population level.

METHODS

We used data from the population-based compulsory Norwegian tuberculosis screening program during 1963 to 1975, including objectively measured height and weight from ≈85% of all eligible citizens. This was combined with data from the Norwegian MS registry and biobank up to November 2020. BMI was standardized according to age and sex, and risk for MS was calculated with Cox proportional hazard models.

RESULTS

During 30,829,506 years of follow-up, we found 1,409 cases of MS among 648,734 participants in eligible age groups (14-34 years). Overall, obesity was associated with increased MS risk (hazard ratio [HR] 1.53 [95% confidence interval (CI) 1.25-1.88]), and the risk was similar in men (HR 1.4 [95% CI 0.95-2.06] and women (HR 1.59 [95% CI 1.25-2.02]). Risk was highest for the youngest age groups (age 14-16: HR 1.73 [95% CI 1.19-2.53]; 17-19: HR 1.61 [95% CI 1.08-2.39]; 20-24: HR 1.56 [95% CI 1.04-2.36]) and was no longer present for those >30 years of age.

DISCUSSION

High BMI in individuals 14 to 24 years of age was associated with increased MS risk later in life in both male and female individuals.

Apparent changes in the epidemiology and severity of multiple sclerosis

Multiple sclerosis (MS) is an immunological disease that causes acute inflammatory lesions and chronic inflammation in the CNS, leading to tissue damage and disability. As awareness of MS has increased and options for therapy have come into use, a large amount of epidemiological data have been collected, enabling studies of changes in incidence and disease course over time. Overall, these data seem to indicate that the incidence of MS has increased, but the course of the disease has become milder, particularly in the 25 years since the first disease-modifying therapies (DMTs) became available. A clear understanding of these trends and the reasons for them is important for understanding the factors that influence the development and progression of MS, and for clinical management with respect to prevention and treatment decisions. In this Review, we consider the evidence for changes in the epidemiology of MS, focusing on trends in the incidence of the disease over time and trends in the disease severity. In addition, we discuss the factors influencing these trends, including refinement of diagnostic criteria and improvements in health-care systems that have increased diagnosis in people with mild disease, and the introduction and improvement of DMT.

Critical Role of Astrocyte NAD+ Glycohydrolase in Myelin Injury and Regeneration

Western-style diets cause disruptions in myelinating cells and astrocytes within the mouse CNS. Increased CD38 expression is present in the cuprizone and experimental autoimmune encephalomyelitis models of demyelination and CD38 is the main nicotinamide adenine dinucleotide (NAD⁺)-depleting enzyme in the CNS. Altered NAD⁺ metabolism is linked to both high fat consumption and multiple sclerosis (MS). Here, we identify increased CD38 expression in the male mouse spinal cord following chronic high fat consumption, after focal toxin [lysolecithin (LL)]-mediated demyelinating injury, and in reactive astrocytes within active MS lesions. We demonstrate that CD38 catalytically inactive mice are substantially protected from high fat-induced NAD⁺ depletion, oligodendrocyte loss, oxidative damage, and astrogliosis. A CD38 inhibitor, 78c, increased NAD⁺ and attenuated neuroinflammatory changes induced by saturated fat applied to astrocyte cultures. Conditioned media from saturated fat-exposed astrocytes applied to oligodendrocyte cultures impaired myelin protein production, suggesting astrocyte-driven indirect mechanisms of oligodendrogliopathy. In cerebellar organotypic slice cultures subject to LL-demyelination, saturated fat impaired signs of remyelination effects that were mitigated by concomitant 78c treatment. Significantly, oral 78c increased counts of oligodendrocytes and remyelinated axons after focal LL-induced spinal cord demyelination. Using a RiboTag approach, we identified a unique in vivo brain astrocyte translatome profile induced by 78c-mediated CD38 inhibition in mice, including decreased expression of proinflammatory astrocyte markers and increased growth factors. Our findings suggest that a high-fat diet impairs oligodendrocyte survival and differentiation through astrocyte-linked mechanisms mediated by the NAD⁺ase CD38 and highlights CD38 inhibitors as potential therapeutic candidates to improve myelin regeneration.SIGNIFICANCE STATEMENT Myelin disturbances and oligodendrocyte loss can leave axons vulnerable, leading to permanent neurologic deficits. The results of this study suggest that metabolic disturbances, triggered by consumption of a diet high in fat, promote oligodendrogliopathy and impair myelin regeneration through astrocyte-linked indirect nicotinamide adenine dinucleotide (NAD⁺)-dependent mechanisms. We demonstrate that restoring NAD⁺ levels via genetic inactivation of CD38 can overcome these effects. Moreover, we show that therapeutic inactivation of CD38 can enhance myelin regeneration. Together, these findings point to a new metabolic targeting strategy positioned to improve disease course in multiple sclerosis and other conditions in which the integrity of myelin is a key concern.

Adipokines as Immune Cell Modulators in Multiple Sclerosis

Multiple sclerosis (MS), a chronic inflammatory and demyelinating disease of the central nervous system (CNS), is a major clinical and societal problem, which has a tremendous impact on the life of patients and their proxies. Current immunomodulatory and anti-inflammatory therapies prove to be relatively effective; however, they fail to concomitantly stop ongoing neurological deterioration and do not reverse acquired disability. The proportion to which genetic and environmental factors contribute to the etiology of MS is still incompletely understood; however, a recent association between MS etiology and obesity was shown, with obesity greatly increasing the risk of developing MS. An altered balance of adipokines, which are white adipose tissue (WAT) hormones, plays an important role in the low-grade chronic inflammation during obesity by their pervasive modification of local and systemic inflammation. Vice versa, inflammatory factors secreted by immune cells affect adipokine function. To explore the role of adipokines in MS pathology, we will here review the reciprocal effects of adipokines and immune cells and summarize alterations in adipokine levels in MS patient cohorts. Finally, we will discuss proof-of-concept studies demonstrating the therapeutic potential of adipokines to target both neuroinflammation and neurodegeneration processes in MS.

Childhood obesity and multiple sclerosis: A Mendelian randomization study

BACKGROUND

Higher childhood body mass index (BMI) has been associated with an increased risk of multiple sclerosis (MS).

OBJECTIVE

To evaluate whether childhood BMI has a causal influence on MS, and whether this putative effect is independent from early adult obesity and pubertal timing.

METHODS

We performed Mendelian randomization (MR) using summary genetic data on 14,802 MS cases and 26,703 controls. Large-scale genome-wide association studies provided estimates for BMI in childhood (n = 47,541) and adulthood (n = 322,154). In multivariable MR, we examined the direct effects of each timepoint and further adjusted for age at puberty. Findings were replicated using the UK Biobank (n = 453,169).

RESULTS

Higher genetically predicted childhood BMI was associated with increased odds of MS (odds ratio (OR) = 1.26/SD BMI increase, 95% confidence interval (CI): 1.07-1.50). However, there was little evidence of a direct effect after adjusting for adult BMI (OR = 1.03, 95% CI: 0.70-1.53). Conversely, the effect of adult BMI persisted independent of childhood BMI (OR = 1.43; 95% CI: 1.01-2.03). The addition of age at puberty did not alter the findings. UK Biobank analyses showed consistent results. Sensitivity analyses provided no evidence of pleiotropy.

CONCLUSION

Genetic evidence supports an association between childhood obesity and MS susceptibility, mediated by persistence of obesity into early adulthood but independent of pubertal timing.

Dietary factors in experimental autoimmune encephalomyelitis and multiple sclerosis: A comprehensive review

BACKGROUND

Dietary intervention in multiple sclerosis carries potential therapeutic implications. While studies utilizing animal models of multiple sclerosis (MS) have demonstrated intriguing findings, well-designed clinical trials are few in number.

OBJECTIVE

The objective of this study is to review the animal model and clinical literature regarding dietary factors in experimental autoimmune encephalitis (EAE) and MS.

METHODS

This manuscript provides a comprehensive review of current animal model and clinical knowledge related to dietary factors in MS.

RESULTS

While there is currently little data for any specific diet in MS, there is growing evidence that certain dietary factors may influence the disease.

CONCLUSIONS

Definitive information regarding dietary factors as a modifiable risk factor in MS will require larger randomized clinical trials.

Multiple Sclerosis: Lipids, Lymphocytes, and Vitamin D

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system. We review the two core MS features, myelin instability, fragmentation, and remyelination failure, and dominance of pathogenic CD4⁺ Th17 cells over protective CD4⁺ Treg cells. To better understand myelin pathology, we describe myelin biosynthesis, structure, and function, then highlight stearoyl-CoA desaturase (SCD) in nervonic acid biosynthesis and nervonic acid's contribution to myelin stability. Noting that vitamin D deficiency decreases SCD in the periphery, we propose it also decreases SCD in oligodendrocytes, disrupting the nervonic acid supply and causing myelin instability and fragmentation. To better understand the distorted Th17/Treg cell balance, we summarize Th17 cell contributions to MS pathogenesis, then highlight how 1,25-dihydroxyvitamin D₃ signaling from microglia to CD4⁺ T cells restores Treg cell dominance. This signaling rapidly increases flux through the methionine cycle, removing homocysteine, replenishing S-adenosyl-methionine, and improving epigenetic marking. Noting that DNA hypomethylation and inappropriate DRB1*1501 expression were observed in MS patient CD4⁺ T cells, we propose that vitamin D deficiency thwarts epigenetic downregulation of DRB1*1501 and Th17 cell signature genes, and upregulation of Treg cell signature genes, causing dysregulation within the CD4⁺ T cell compartment. We explain how obesity reduces vitamin D status, and how estrogen and vitamin D collaborate to promote Treg cell dominance in females. Finally, we discuss the implications of this new knowledge concerning myelin and the Th17/Treg cell balance, and advocate for efforts to address the global epidemics of obesity and vitamin D deficiency in the expectation of reducing the impact of MS.

Multiple sclerosis among first- and second-generation immigrants in Denmark: a population-based cohort study

Multiple sclerosis is a disease with a highly variable incidence worldwide. While knowledge about multiple sclerosis risk factors has grown over the years, the aetiology of multiple sclerosis has still not been fully established. We examined multiple sclerosis incidence rates among first-generation immigrants in Denmark, a high-incidence country, and their Danish-born children (second-generation immigrants), to evaluate the importance and timing of exposure to environmental factors in the aetiology of multiple sclerosis. By means of the Danish Civil Registration System we identified 9 121 187 individuals living in Denmark between 1968 and 2015, including 1 176 419 first-generation and 184 282 second-generation immigrants. Study participants were followed for multiple sclerosis in the Danish Multiple Sclerosis Registry from 1968 to 2015. The relative risk (RR) of multiple sclerosis according to immigration status was estimated by means of multiple sclerosis incidence rate ratios obtained in log-linear Poisson regression analysis. Altogether, 16 905 cases of multiple sclerosis were identified in the study cohort, 578 among first-generation and 106 among second-generation immigrants. Multiple sclerosis risk among first-generation immigrants whose parents were born in low, intermediate and high multiple sclerosis risk areas were 21% (RR = 0.21; 95% CI: 0.16-0.28), 43% (RR = 0.43; 95% CI: 0.36-0.50) and 75% (RR = 0.75; 95% CI: 0.67-0.83), respectively, of that among ethnic Danes (test for trend P < 0.0001). First-generation immigrants arriving in Denmark before age 15 years had a multiple sclerosis risk higher than that in their country of birth but lower than that in Denmark, reaching on average 69% of the multiple sclerosis risk among ethnic Danes (RR = 0.69; 95% CI: 0.55-0.87). Multiple sclerosis risk among individuals who came to Denmark at a later age remained closer to that of their country of birth, corresponding to 45% of the multiple sclerosis risk among ethnic Danes (RR = 0.45; 95% CI: 0.41-0.49). Our study supports the idea that environmental factors exerting their role in childhood or adolescence may be of aetiological relevance in multiple sclerosis.

High fat diet consumption results in mitochondrial dysfunction, oxidative stress, and oligodendrocyte loss in the central nervous system

Metabolic syndrome is a key risk factor and co-morbidity in multiple sclerosis (MS) and other neurological conditions, such that a better understanding of how a high fat diet contributes to oligodendrocyte loss and the capacity for myelin regeneration has the potential to highlight new treatment targets. Results demonstrate that modeling metabolic dysfunction in mice with chronic high fat diet (HFD) consumption promotes loss of oligodendrocyte progenitors across the brain and spinal cord. A number of transcriptomic and metabolomic changes in ER stress, mitochondrial dysfunction, and oxidative stress pathways in HFD-fed mouse spinal cords were also identified. Moreover, deficits in TCA cycle intermediates and mitochondrial respiration were observed in the chronic HFD spinal cord tissue. Oligodendrocytes are known to be particularly vulnerable to oxidative damage, and we observed increased markers of oxidative stress in both the brain and spinal cord of HFD-fed mice. We additionally identified that increased apoptotic cell death signaling is underway in oligodendrocytes from mice chronically fed a HFD. When cultured under high saturated fat conditions, oligodendrocytes decreased both mitochondrial function and differentiation. Overall, our findings show that HFD-related changes in metabolic regulators, decreased mitochondrial function, and oxidative stress contribute to a loss of myelinating cells. These studies identify HFD consumption as a key modifiable lifestyle factor for improved myelin integrity in the adult central nervous system and in addition new tractable metabolic targets for myelin protection and repair strategies.

Leptin levels are associated with multiple sclerosis risk

BACKGROUND

Obesity early in life has been linked to increased risk of developing multiple sclerosis (MS). Leptin and insulin are both associated with obesity, making them suitable candidates for investigating this connection.

OBJECTIVE

To determine if leptin and insulin are risk factors for relapsing-remitting multiple sclerosis (RRMS).

METHODS

In this nested case-control study using blood samples from Swedish biobanks, we compared concentrations of leptin and insulin in 649 individuals who later developed RRMS with 649 controls matched for biobank, sex, age and date of sampling. Only pre-symptomatically drawn samples from individuals below the age of 40 years were included. Conditional logistic regression was performed on z-scored values to calculate odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

A 1-unit leptin z-score increase was associated with increased risk of MS in individuals younger than 20 years (OR = 1.4, 95% CI = 1.1-1.9) and in all men (OR = 1.4, 95% CI = 1.0-2.0). In contrast, for women aged 30-39 years, there was a lower risk of MS with increased leptin levels (OR = 0.74, 95% CI = 0.54-1.0) when adjusting for insulin levels.

CONCLUSION

We show that the pro-inflammatory adipokine leptin is a risk factor for MS among young individuals.

Association of Obesity With Multiple Sclerosis Risk and Response to First-line Disease Modifying Drugs in Children

Importance

Obesity reportedly increases the risk of pediatric multiple sclerosis (MS), but little is known about its association with disease course.

Objective

To investigate the association of obesity with pediatric MS risk and with first-line therapy response among children with MS.

Design, Setting, and Participants

This single-center retrospective study used the medical records and database at the Center for MS in Childhood and Adolescence, Göttingen, Germany. The study included 453 patients with relapsing-remitting pediatric MS and body mass index (BMI) measurement taken within 6 months of diagnosis. Onset of the disease occurred between April 28, 1990, and June 26, 2016, and the mean disease duration was 38.4 months. Data were collected from July 14, 2016, to December 18, 2017.

Main Outcomes and Measures

Data on BMIs were stratified by sex and age using German BMI references and compared with the BMI data of 14 747 controls from a nationwide child health survey for odds ratio (OR) estimates. Baseline magnetic resonance imaging findings, intervals between first and second MS attacks, annualized relapse rates before and during treatment with interferon beta-1a or -1b and glatiramer acetate, frequency of second-line treatment, and Expanded Disability Status Scale (EDSS) scores were compared between nonoverweight (BMI≤90th percentile), overweight (BMI>90th-97th percentile), and obese (BMI>97th percentile) patients.

Results

In total, 453 patients with pediatric MS were included, of whom 306 (67.5%) were female, and the mean (SD) age at diagnosis was 13.7 (2.7) years. At diagnosis, 126 patients (27.8%) were overweight or obese, with obesity associated with statistically significant twofold odds of MS in both sexes (girls OR, 2.19; 95% CI, 1.5-3.1; P < .001 vs boys OR, 2.14; 95% CI, 1.3-3.5; P = .003). Obese patients, compared with nonoverweight patients, had statistically significantly more relapses on first-line treatment with interferon beta and glatiramer acetate (ARR, 1.29 vs 0.72; P < .001) and a higher rate of second-line treatment (21 [56.8%] of 37 vs 48 [38.7%] of 124; P = .06). Baseline neuroimaging, interval between first and second MS attacks, pretreatment relapses, and EDSS progression scores were not correlated with BMI.

Conclusions and Relevance

In this study, increased pediatric MS risk appeared to be associated with obesity, and obese patients did not respond well to first-line medications; altered pharmacokinetics appeared to be most likely factors in treatment response, suggesting that achieving healthy weight or adjusting the dose according to BMI could improve therapy response.

The role of testosterone in MS risk and course

There is significant animal model data demonstrating a benefit of testosterone on both inflammatory and neuroprotective mechanisms relevant to multiple sclerosis (MS). Several studies have demonstrated lowered testosterone levels in up to 40% of men with MS. Lower testosterone levels were correlated with worsened scores of physical and cognitive disability. There is increasing data suggesting a role of testosterone in MS risk. A pilot study has demonstrated significant benefits of testosterone replacement therapy on cognitive, radiological, and immunological outcome measures in men with MS. Larger studies in other conditions have demonstrated concerns in terms of cardiovascular risk, which indicate the need for careful monitoring upon administration to MS patients. Further studies are needed to develop safer testosterone preparations, which preserve its multiple beneficial effects, as well as multicenter clinical trials to evaluate safety, dosing, and efficacy in larger populations of men with MS. Additionally, studies are needed to further explore the role of androgens as a risk factor for MS, particularly at key life transitions.

Epstein-barr virus and multiple sclerosis risk in the finnish maternity cohort

OBJECTIVE

To determine whether maternal Epstein-Barr virus (EBV) IgG antibody levels are associated with risk of multiple sclerosis (MS) in the offspring.

METHODS

We conducted a prospective nested case-control study in the Finnish Maternity Cohort (FMC) with serum samples from >800,000 women collected during pregnancy since 1983. Cases of MS among offspring born between 1983 and 1991 were identified via hospital and prescription registries; 176 cases were matched to up to 3 controls (n = 326) on region and dates of birth, sample collection, and mother's birth. We used conditional logistic regression to estimate relative risks (RRs) and adjusted models for sex of the child, gestational age at sample collection, and maternal serum 25-hydroxyvitamin D and cotinine levels. Similar analyses were conducted among 1,049 women with MS and 1,867 matched controls in the FMC.

RESULTS

Maternal viral capsid antigen IgG levels during pregnancy were associated with an increased MS risk among offspring (RR_{top vs bottom quintile} = 2.44, 95% confidence interval [CI] = 1.20-5.00, p trend = 0.004); no associations were found between maternal EBV nuclear antigen 1 (EBNA-1), diffuse early antigen, or cytomegalovirus IgG levels and offspring MS risk. Among women in the FMC, those in the highest versus lowest quintile of EBNA-1 IgG levels had a 3-fold higher risk of MS (RR = 3.21, 95% CI = 2.37-4.35, p trend <1.11e-16). These associations were not confounded or modified by 25-hydroxyvitamin D.

INTERPRETATION

Offspring of mothers with high viral capsid antigen IgG during pregnancy appear to have an increased risk of MS. The increase in MS risk among women with elevated prediagnostic EBNA-1 IgG levels is consistent with previous results. ANN NEUROL 2019;86:436-442.

Relationship between the use of electronic devices and susceptibility to multiple sclerosis

Multiple sclerosis (MS) is an autoimmune condition influenced by both genetic and environmental factors. Dirty electricity generated by electronic equipment is one of the environmental factors that may directly or indirectly impact MS susceptibility. The current Study aimed to evaluate the relationship between the usage time of electronic equipment and susceptibility to MS in North-West Iranian people. This approach was carried out upon 471 MS-diagnosed patients and 453 healthy participants as control group in East Province of Azerbaijan. By utilizing structured questionnaires, the information of all participants about usage status of some electronic devices was obtained. Data were analyzed by IBM SPSS Statistics version 18.0 and the quantitative variables were analyzed by Chi Square and Independent sample t tests. P values below or equal to 0.05 were considered as significant. Among the evaluated items in this approach, the utilization of cell phones and satellite television dishes were significantly higher in MS patients (p < 0.001, p = 0.07). Furthermore, a correlation was observed between sleeping with cell phone and/or laptop under the pillow (p = 0.011) and MS disease; however, there was no significant differences between MS patients and controls in computer using and television watching. Our study reinforces the concept that the utilization of some electronic devices and the continuous exposure to dirty electricity would increase the risk of MS disease thereupon by enhancing the cognizance of adverse effects of dirty electricity and reducing the time spent over electronic devices during adolescence and adulthood the occurrence probability of MS could be declined.

Body Mass Index in Multiple Sclerosis modulates ceramide-induced DNA methylation and disease course

BACKGROUND

Multiple Sclerosis (MS) results from genetic predisposition and environmental variables, including elevated Body Mass Index (BMI) in early life. This study addresses the effect of BMI on the epigenome of monocytes and disease course in MS.

METHODS

Fifty-four therapy-naive Relapsing Remitting (RR) MS patients with high and normal BMI received clinical and MRI evaluation. Blood samples were immunophenotyped, and processed for unbiased plasma lipidomic profiling and genome-wide DNA methylation analysis of circulating monocytes. The main findings at baseline were validated in an independent cohort of 91 therapy-naïve RRMS patients. Disease course was evaluated by a two-year longitudinal follow up and mechanistic hypotheses tested in human cell cultures and in animal models of MS.

FINDINGS

Higher monocytic counts and plasma ceramides, and hypermethylation of genes involved in negative regulation of cell proliferation were detected in the high BMI group of MS patients compared to normal BMI. Ceramide treatment of monocytic cell cultures increased proliferation in a dose-dependent manner and was prevented by DNA methylation inhibitors. The high BMI group of MS patients showed a negative correlation between monocytic counts and brain volume. Those subjects at a two-year follow-up showed increased T1 lesion load, increased disease activity, and worsened clinical disability. Lastly, the relationship between body weight, monocytic infiltration, DNA methylation and disease course was validated in mouse models of MS.

INTERPRETATION

High BMI negatively impacts disease course in Multiple Sclerosis by modulating monocyte cell number through ceramide-induced DNA methylation of anti-proliferative genes. FUND: This work was supported by funds from the Friedman Brain Institute, NIH, and Multiple Sclerosis Society.

Cognitive Functioning in Patients with Pediatric-Onset Multiple Sclerosis, an Updated Review and Future Focus

Pediatric-onset multiple sclerosis (POMS) is relatively rare, but as technology and neuroimaging advance, an increasing number of cases are identified, and our understanding of how multiple sclerosis (MS) impacts the developing brain improves. There are consistent findings in the literature highlighting the impact of MS and other demyelinating diseases on cognitive functioning and cognitive development. We also have a better understanding of how POMS impacts psychosocial functioning and functional outcomes in daily living. This paper hopes to review findings associated with cognitive and psychosocial functioning in patients with POMS, as well as explore more recent advances in the field and how they relate to cognitive and psychosocial outcomes. We also discuss the ongoing need for future studies with a focus on better understanding deficits and disease correlates, but also preventative measures and potential rehabilitation.

Multiple sclerosis

Multiple sclerosis (MS) is the most common chronic inflammatory, demyelinating and neurodegenerative disease of the central nervous system in young adults. This disorder is a heterogeneous, multifactorial, immune-mediated disease that is influenced by both genetic and environmental factors. In most patients, reversible episodes of neurological dysfunction lasting several days or weeks characterize the initial stages of the disease (that is, clinically isolated syndrome and relapsing-remitting MS). Over time, irreversible clinical and cognitive deficits develop. A minority of patients have a progressive disease course from the onset. The pathological hallmark of MS is the formation of demyelinating lesions in the brain and spinal cord, which can be associated with neuro-axonal damage. Focal lesions are thought to be caused by the infiltration of immune cells, including T cells, B cells and myeloid cells, into the central nervous system parenchyma, with associated injury. MS is associated with a substantial burden on society owing to the high cost of the available treatments and poorer employment prospects and job retention for patients and their caregivers.

Longitudinal Associations of the Healthy Lifestyle Index Score With Quality of Life in People With Multiple Sclerosis: A Prospective Cohort Study

Objective: To explore the association between combined lifestyle risk factors with quality of life in people with multiple sclerosis (MS) over 2.5 years. Methods: People with MS were recruited to participate in a comprehensive online survey regarding their demographic and clinical characteristics, health-related quality of life (HRQOL), and lifestyle behaviors including physical activity, alcohol consumption, cigarette smoking, body mass index, and dietary habits measured at baseline and 2.5-year follow-up. A combined healthy lifestyle index score (HLIS) was constructed by assigning scores of 0-4 to each of the lifestyle risk factors, for which higher values indicate healthier lifestyle behavior. Multivariable linear regression modeling was used to assess whether the HLIS at baseline was associated with the physical and mental HRQOL over the study period in this sample of people with MS. Results: Of 2,466 participants with confirmed MS, 1,401 (57%) completed the follow-up. Multivariable linear regression analyses demonstrated that every 5-point increase (of a possible total of 20) in the baseline HLIS was associated with 1.7 (95% CI: 0.2-3.2) and 2.5 (95% CI: 1.0-4.0) higher scores in the change in physical and mental HRQOL components from baseline to follow-up respectively. Conclusion: Findings suggest the importance of healthy lifestyle behavior in quality of life in MS. A healthy lifestyle program focusing on these behaviors has the potential to positively influence health-related quality of life for people with MS.

Alcohol consumption in adolescence is associated with a lower risk of multiple sclerosis in a Danish cohort

BACKGROUND AND OBJECTIVE

Due to the possible existence of a vulnerable period of multiple sclerosis (MS) susceptibility in adolescence and because Danish teenagers have a high alcohol consumption, we investigated the association between alcohol consumption at ages 15-19 and the risk of developing MS.

METHODS

A total of 1717 patients with MS and 4685 healthy blood donors filled in a comprehensive environmental and lifestyle questionnaire. Data were analysed by logistic regression models and adjusted for selected confounders.

RESULTS

We found an inverse association between alcohol consumption in adolescence and risk of developing MS in both women (p < 0.001) and men (p = 0.012). Women with low alcohol consumption had an odds ratio (OR) of 0.56 (95% confidence interval (CI): 0.47-0.66) compared with non-drinking women. The ORs were similar for women with moderate (OR = 0.49, 95% CI: 0.38-0.62) and high consumption (OR = 0.57, 95% CI: 0.38-0.84). Men with low alcohol consumption had an OR of 0.69 (95% CI: 0.53-0.89) compared with non-drinking men but no decreased risk was found for men with moderate and high consumption.

CONCLUSION

Alcohol consumption in adolescence was associated with lower risk of developing MS among both sexes.

Multiple Sclerosis in the Contemporary Age: Understanding the Millennial Patient with Multiple Sclerosis to Create Next-Generation Care

The average age of onset of multiple sclerosis (MS) is between 20 and 40 years of age. Therefore, most new patients diagnosed with MS within the next 10 to 15 years will be from the millennial generation, representing those born between 1982 and 2000. Certain preferences and trends of this contemporary generation will present new challenges to the MS physician and effective MS care. By first understanding these challenges, relevant and successful solutions can be created to craft a system of care that best benefits the millennial patient with MS.

Incorporating machine learning approaches to assess putative environmental risk factors for multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) incidence has increased recently, particularly in women, suggesting a possible role of one or more environmental exposures in MS risk. The study objective was to determine if animal, dietary, recreational, or occupational exposures are associated with MS risk.

METHODS

Least absolute shrinkage and selection operator (LASSO) regression was used to identify a subset of exposures with potential relevance to disease in a large population-based (Kaiser Permanente Northern California [KPNC]) case-control study. Variables with non-zero coefficients were analyzed in matched conditional logistic regression analyses, adjusted for established environmental risk factors and socioeconomic status (if relevant in univariate screening),± genetic risk factors, in the KPNC cohort and, for purposes of replication, separately in the Swedish Epidemiological Investigation of MS cohort. These variables were also assessed in models stratified by HLA-DRB1*15:01 status since interactions between risk factors and that haplotype have been described.

RESULTS

There was a suggestive association of pesticide exposure with having MS among men, but only in those who were positive for HLA-DRB1*15:01 (OR pooled = 3.11, 95% CI 0.87, 11.16, p = 0.08).

CONCLUSIONS

While this finding requires confirmation, it is interesting given the association between pesticide exposure and other neurological diseases. The study also demonstrates the application of LASSO to identify environmental exposures with reduced multiple statistical testing penalty. Machine learning approaches may be useful for future investigations of concomitant MS risk or prognostic factors.

The Relationship of adiponectin level and ADIPOQ gene variants with BMI among young adult women

The current study examined the effect of single nucleotide (SNPs) polymorphisms in the ADIPOQ gene (I146T and G276T) on body mass index (BMI) of young adult women. The women were divided into underweight, normal, overweight and obese according to BMI. The circulating levels of adiponectin were measured using commercially available ELISA kits. Genetic polymorphisms were genotyped using the PCR-RFLP method. G276T and I164T SNPs are common in the examined population as the frequency of G allele of 276 SNP was 54.8% and for the T allele of 164 SNP it was 41.7%. Circulating adiponectin levels were related to BMI and were lowest in the obese versus overweight, normal weight and underweight groups (p<0.01). However, ADIPOQ gene SNPs (I146T and G276T) showed no association with BMI groups. In conclusion, the results may suggest that adiponectin level, but not ADIPOQ gene SNPs, is a good indicator to BMI in young adult women.

Changes in Nutritional Status Impact Immune Cell Metabolism and Function

Immune cell function and metabolism are closely linked. Many studies have now clearly demonstrated that alterations in cellular metabolism influence immune cell function and that, conversely, immune cell function determines the cellular metabolic state. Less well understood, however, are the effects of systemic metabolism or whole organism nutritional status on immune cell function and metabolism. Several studies have demonstrated that undernutrition is associated with immunosuppression, which leads to both increased susceptibility to infection and protection against several types of autoimmune disease, whereas overnutrition is associated with low-grade, chronic inflammation that increases the risk of metabolic and cardiovascular disease, promotes autoreactivity, and disrupts protective immunity. Here, we review the effects of nutritional status on immunity and highlight the effects of nutrition on circulating cytokines and immune cell populations in both human studies and mouse models. As T cells are critical members of the immune system, which direct overall immune response, we will focus this review on the influence of systemic nutritional status on T cell metabolism and function. Several cytokines and hormones have been identified which mediate the effects of nutrition on T cell metabolism and function through the expression and action of key regulatory signaling proteins. Understanding how T cells are sensitive to both inadequate and overabundant nutrients may enhance our ability to target immune cell metabolism and alter immunity in both malnutrition and obesity.