Obesity and Multiple Sclerosis—A Multifaceted Association

Abstract

Background: Given the common elements in the pathophysiological theories that try to explain the appearance and evolution of obesity and multiple sclerosis, the association between the two pathologies has become an increasingly researched topic in recent years. On the one hand, there is the chronic demyelinating inflammation caused by the autoimmune cascade of multiple sclerosis, while on the other hand, according to the latest research, it has been shown that obesity shares an inflammatory component with most chronic diseases. Methods: The authors performed independent research of the available literature in the most important electronic databases (PubMed, Google Scholar, Embase, and Science Direct) in February 2021. After applying the exclusion criteria, the reviewers focused on the most relevant articles published during the last 10 years with respect to epidemiology and pathophysiology. Results: The data presented are a step forward in trying to elucidate the intricate relationship between obesity and MS, especially the causal relationship between childhood and adolescent obesity and MS, focusing on the epidemiological associations observed in the most relevant observational studies conducted in recent years. In the second part, the authors comment on the latest findings related to the pathophysiological mechanisms that may explain the correlations between obesity and multiple sclerosis, focusing also on the role of adipokines. Conclusions: Based on available epidemiological data, obesity in early life appears to be strongly associated with a higher risk of MS development, independent of other risk factors. Although much research has been done on the pathophysiology of obesity, MS, their possible common mechanism, and the role of adipokines, further studies are needed in order to explain what remains unknown. No relevant data were found regarding the association between obesity, disability (high EDSS score), and mortality risk in MS patients. Thus, we consider that this topic should be elucidated in future research.

Risk Factors from Pregnancy to Adulthood in Multiple Sclerosis Outcome

“…Interestingly, there is a multifaceted association between obesity and MS. High body mass index (BMI) genetic variants in adolescent and adult patients are associated with the onset of MS [58,59]. Autoimmune diseases are usually associated with polymorphisms of the genes that regulate the function of the immune system; in this context, the HLA antigen D-related β1 subunit (DRB1) gene (HLA DRB1*15:01), within the major histocompatibility complex, has been identified as the primary locus associated with this correlation [58,60]. Furthermore, obesity is also correlated with the development of MS due to the polymorphisms found in fat mass obesity (FTO)-related genes [61,62].…”

“…The FTO rs9939609 polymorphism has consistently been associated with a higher BMI across different populations, including the Kuwaiti population [63]. Another link between MS and obesity is the adipokine's capacity to modulate the immune system by increasing pro-inflammatory response [58,59]. It is still necessary to deeply understand how these risk genetic variants are regulated and the pathways in which they are involved in the immune system of these patients [54].…”

Microbiome First Medicine in Health and Safety

“…Obesity is one of the major conditions that gives rise to a myriad of comorbid, inflammation driven, chronic diseases particularly as aging progresses [ 62 , 63 ]. Table 2 illustrates examples of 43 comorbid NCDs for obesity [ 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 ]. The obese population carries one of the highest risks for multiple future NCDs of any disease-burdened cohort.…”

High-fat diet-induced intestinal dysbiosis is associated with the exacerbation of Sjogren’s syndrome

“…It is well known that HFD contributes to systemic low-grade inflammation in the body (Duan et al, 2018). Furthermore, many studies reported that HFD-induced inflammation can exacerbate the progression of autoimmune diseases, such as multiple sclerosis (Schreiner and Genes, 2021), systemic lupus erythematosus (SLE; Hanna Kazazian et al, 2019), and rheumatoid arthritis (RA; Poudel et al, 2020). However, there are few studies elucidating the relationship between HFD and pSS.…”