Allostatic load index in patients with multiple sclerosis: A case-control study

Dietary Modification Combined with Nutrition Education and Counseling for Metabolic Comorbidities in Multiple Sclerosis: Implications for Clinical Practice and Research

PURPOSE OF REVIEW

Metabolic comorbidities such as obesity, diabetes, hypertension, and dyslipidemia are common to multiple sclerosis (MS) and are associated with negative outcomes of the disease. Dietary intervention has the potential to improve MS co-morbidities; thus, it is a high priority for people living with MS to self-manage their disease. The present review aimed to summarize the recent evidence on the impacts of combining dietary modification with nutrition education and counseling on managing metabolic comorbidity markers in MS.

RECENT FINDINGS

Evidence suggests important roles for tailored dietary change strategies and nutrition education and counseling in managing metabolic comorbidities for MS. There is also indirect evidence suggesting a relationship between dietary fiber, the gut microbiome, and improved metabolic markers in MS, highlighting the need for more research in this area. For people living with MS, addressing both barriers and facilitators to dietary changes through behavior change techniques can help them achieve sustainable and tailored dietary behavior changes. This will support person-centered care, ultimately improving metabolic comorbidity outcomes. Metabolic comorbidities in MS are considered modifiable diseases that can be prevented and managed by changes in dietary behavior. However, the impact of targeted dietary interventions on mitigating MS-related metabolic comorbidities remains inadequately explored. Therefore, this review has provided insights into recommendations to inform future best practices in MS. Further well-designed studies based on tailored dietary strategies applying behavior change theories are needed to address the underlying determinants of dietary practice in this population.

Emerging Theories of Allostatic-Interoceptive Overload in Neurodegeneration

Recent integrative multilevel models offer novel insights into the etiology and course of neurodegenerative conditions. The predictive coding of allostatic-interoception theory posits that the brain adapts to environmental demands by modulating internal bodily signals through the allostatic-interoceptive system. Specifically, a domain-general allostatic-interoceptive network exerts adaptive physiological control by fine-tuning initial top-down predictions and bottom-up peripheral signaling. In this context, adequate adaptation implies the minimization of prediction errors thereby optimizing energy expenditure. Abnormalities in top-down interoceptive predictions or peripheral signaling can trigger allostatic overload states, ultimately leading to dysregulated interoceptive and bodily systems (endocrine, immunological, circulatory, etc.). In this context, environmental stress, social determinants of health, and harmful exposomes (i.e., the cumulative life-course exposition to different environmental stressors) may interact with physiological and genetic factors, dysregulating allostatic interoception and precipitating neurodegenerative processes. We review the allostatic-interoceptive overload framework across different neurodegenerative diseases, particularly in the behavioral variant frontotemporal dementia (bvFTD). We describe how concepts of allostasis and interoception could be integrated with principles of predictive coding to explain how the brain optimizes adaptive responses, while maintaining physiological stability through feedback loops with multiple organismic systems. Then, we introduce the model of allostatic-interoceptive overload of bvFTD and discuss its implications for the understanding of pathophysiological and neurocognitive abnormalities in multiple neurodegenerative conditions.

Heart Rate Variability (HRV) serves as an objective correlate of distress and symptom burden in multiple sclerosis

Background

Autonomic nervous system (ANS) dysfunction is frequently seen in people living with multiple sclerosis (MS). Heart rate variability (HRV) is an easy and objective index for evaluating ANS functioning, and it has been previously used to explore the association between ANS and the experience of symptom burden in other chronic diseases. Given ANS functioning can be influenced by physical and psychological factors, this study investigated whether emotional distress and/or the presence of ANS dysfunction is associated with symptom severity in people living with MS.

Methods

Participants with MS and healthy controls (HC) with no history of cardiac conditions were recruited to self-collect HR data sampled from a chest strap HR monitor (PolarH10). Short-term HR signal was collected for five minutes, and time and frequency HRV analyses were performed and compared between groups. HRV values were then compared to self-reported distress (Kessler Psychological Distress Scale) and MS participants' self-reported measures of symptom burden (SymptoMScreen).

Results

A total of n = 23 adults with MS (51 ± 12 years, 65 % female, median Patient Determined Disease Steps [PDDS]: 3.0) and n = 23 HCs (43 ± 18 years, 40 % female) completed the study procedures. All participants were able to complete the chest strap placement and HR data capture independently. Participants with MS, compared to the HC participants, had a significantly lower parasympathetic activation as shown by lower values of the root mean square of successive differences between normal heartbeats (RMSSD: 21.86 ± 9.84 vs. 43.13 ± 20.98 ms, p = 0.002) and of high-frequency (HF) power band (HF-HRV: 32.69 ± 12.01 vs. 42.39 ± 7.96 nu, p = 0.016), indicating an overall lower HRV in the MS group. Among individuals with MS, HF-HRV was significantly correlated with the severity of self-reported MS symptoms (r = -0.548, p = 0.010). Participants with MS also reported higher levels of distress compared to HC participants (18.32 ± 6.05 vs. 15.00 ± 4.61, p = 0.050), and HRV correlated with the severity of distress in MS participants (r = -0.569, p = 0.007). A significant mediation effect was also observed, with emotional distress fully mediating the association between HRV and symptom burden.

Conclusions

These findings suggest the potential for ANS dysfunction, as measured by HRV (i.e., lower value of HF power), to be utilized as an objective marker of symptom burden in people living with MS. Moreover, it is apparent that the relationship between HRV and symptom burden is mediated by emotional distress.

Intrinsic timescales and predictive allostatic interoception in brain health and disease

The cognitive neuroscience of brain diseases faces challenges in understanding the complex relationship between brain structure and function, the heterogeneity of brain phenotypes, and the lack of dimensional and transnosological explanations. This perspective offers a framework combining the predictive coding theory of allostatic interoceptive overload (PAIO) and the intrinsic neural timescales (INT) theory to provide a more dynamic understanding of brain health in psychiatry and neurology. PAIO integrates allostasis and interoception to assess the interaction between internal patterns and environmental stressors, while INT shows that different brain regions operate on different intrinsic timescales. The allostatic overload can be understood as a failure of INT, which involves a breakdown of proper temporal integration and segregation. This can lead to dimensional disbalances between exteroceptive/interoceptive inputs across brain and whole-body levels (cardiometabolic, cardiovascular, inflammatory, immune). This approach offers new insights, presenting novel perspectives on brain spatiotemporal hierarchies and interactions. By integrating these theories, the paper opens innovative paths for studying brain health dynamics, which can inform future research in brain health and disease.

Effects of nutrition education given to persons with multiple sclerosis and their families on diet quality and anthropometric and biochemical measurements

ABSTRACT Objective: In this study, it was aimed to investigate the effects of nutrition education given to persons with multiple sclerosis and their families on anthropometric and biochemical measurements and diet quality. Methods: Data from 51 persons with multiple sclerosis were analysed in this intervention study. The study was conducted with 3 groups. The education group consisted of only persons with multiple sclerosis, the family education group consisted of persons with multiple sclerosis and a family member living with them, and the control group consisted of persons with multiple sclerosis who had not received an education. Anthropometric and biochemical measurements and dietary quality assessments were made before (T1) and immediately after education (T2) and also 3 months after education (follow-up, T3). Results: The distribution of family education group diet quality scores showed a significant increase from “poor” to “needs improvement” at T3 compared to T1. The upper middle arm circumference measurements of the female control group were decreased at T2 and T3 [from 29.0 (23-34) cm to 28.0 (22-31) cm and to 27.5 (22-31) cm]. Women in family education group, levels of serum haemoglobin and haematocrit were higher than in control group at T2 and T3. Also, men in family education group, levels of alanine aminotransferase were lower than those in education group at follow up. Levels of total cholesterol and low-density lipoprotein cholesterol in education group were higher than those control group at T1, T2, and T3. Conclusion: This study indicates that nutrition education affects some biochemical and anthropometric measurements in persons with multiple sclerosis. Diet quality improved when receiving education together with families.