Sensitivity to heat in MS patients: a factor strongly influencing symptomology--an explorative survey

The effect of cold-water mouth swilling on thermal perceptions and heat-related symptoms for people with multiple sclerosis exercising in a hot environment

PURPOSE

Cold-water ingestion improves exercise capacity in the heat for people with multiple sclerosis (MS). Whether cold-water ingestion also mitigates heat-related MS symptoms is unknown. Ingesting fluid is also limiting for people with MS with impaired bladder function. Therefore, we tested the hypothesis that swilling or ingesting cold-water (7°C) compared to ingesting thermoneutral water (37°C) would mitigate the onset of perceived MS heat-related symptoms and thermal sensation in heat-sensitive people with MS during exercise in the heat.

METHODS

On three occasions, 13 heat-sensitive participants with MS (41 ± 12 y; 67 ± 12 kg; 1.7 ± 0.1 m; 33.3 ± 9.4 ml·kg-1·min-1) cycled at 40% VO2max at 35 ± 1°C; 30 ± 2% RH until volitional exhaustion (maximum of 60 min). Every 15 min, participants ingested (7IN) or swilled (7SW) 7°C, or ingested 37°C (37IN) water. Thermal sensation, heat-related MS symptoms, rectal (Tre), and mean skin (Tsk) temperature were recorded throughout.

RESULTS

Thermal sensation was cooler in the 7SW (P < 0.01) and 7IN (P = 0.04) compared to the 37IN trial, but heat-related symptoms (P = 0.57), fatigue (P = 0.90), ΔTre (37IN: 0.74 ± 0.37°C; 7IN: 0.65 ± 0.38°C; 7SW: 0.67 ± 0.34°C; P = 0.38) and ΔTsk (37IN: 1.61 ± 0.82°C; 7IN: 1.67 ± 0.78°C; 7SW: 1.64 ± 0.69°C; P = 0.91), were not different between trials. Nine participants completed 60 min of exercise in the 37IN trial whereas 10 participants completed 60 min of exercise in the 7IN and 7SW trials.

CONCLUSION

Swilling and ingesting 7°C water induces a cooler thermal sensation in heat-sensitive people with MS exercising in the heat but does not mitigate heat-related MS symptoms. The capacity to complete 60 min of exercise with cold-water ingestion and swilling were comparable.

A Heat Sensitivity Scale for People with Parkinson's Disease

BACKGROUND

People living with Parkinson's disease (PD) commonly experience heat sensitivity-worsening symptoms and restricted daily activities in heat.

OBJECTIVE

This study aimed to develop a scale of heat sensitivity for people with PD.

METHODS

Through a search of the scientific literature and online forums, we developed 41 items relating to experiences of heat for people with PD to assess heat sensitivity. A panel of experts was then consulted to review the scale items critically. After two rounds of review, the scale was refined to 36 items with an overall scale content validity index of 0.89. Via an online survey, 247 people with PD responded to the items.

RESULTS

The items were examined with exploratory factor analysis to determine the underlying factors therein. After several iterations, a simple structure was achieved with 29 items loading uniquely onto one of four factors: daily activities, sweating and exercise, heat-related illness, and symptoms and medications. The model had acceptable to excellent fit statistics (root mean square error of approximation = 0.073 [90% confidence interval 0.067-0.081], root mean square of the residuals = 0.03, comparative fit index = 0.93, and Tucker-Lewis index = 0.91), and each factor showed high reliability (Cronbach's α ≥0.89). Factor and total scale scores were significantly higher among those reporting sensitivity to heat and poor health status.

CONCLUSION

This new heat sensitivity scale for people living with PD can enable health professionals and clients to assess the severity and impact of heat sensitivity.

Climate change and multiple sclerosis: Clinical challenges and strategies

Climate change poses significant challenges for people with multiple sclerosis (PwMS), exacerbating symptoms such as heat sensitivity. Increasing levels of air pollution contribute to neuroinflammation and has been associated with symptom flares, and mobility impairments complicate resource access for PwMS during climate-related weather emergencies. This paper explores the broad implications of climate change on multiple sclerosis (MS) and offers strategies for clinicians to address these emerging challenges, as understanding the broad impacts of climate change on MS is crucial to provide effective care in a changing world.

Weathering the Pain: Ambient Temperature's Role in Chronic Pain Syndromes

PURPOSE OF REVIEW

Chronic pain is highly prevalent and involves a complex interaction of sensory, emotional, and cognitive processes, significantly influenced by ambient temperature. Despite advances in pain management, many patients continue to experience inadequate pain relief. This review aims to consolidate and critically evaluate the current evidence on the impact of ambient temperature on chronic pain conditions such as fibromyalgia (FM), multiple sclerosis (MS), complex regional pain syndrome (CRPS), and osteoarthritis (OA).

RECENT FINDINGS

Patients with FM often report pain exacerbations due to temperature changes, with studies showing lower thresholds for heat and cold-induced pain compared to healthy controls. In MS, the Uhthoff phenomenon, characterized by temperature-induced neurological deterioration, underscores the significance of ambient temperature in pain management. CRPS patients exhibit heightened pain sensitivity to temperature changes, with both warm and cold stimuli potentially aggravating symptoms. OA patients frequently report increased pain and rigidity associated with lower temperatures and higher humidity. Understanding the mechanisms through which temperature influences pain can enhance pain management strategies. This review highlights the need for further research to elucidate these mechanisms and develop targeted interventions, ultimately improving the quality of life for individuals with chronic pain conditions.

Exercise-induced heat sensitivity in patients with multiple sclerosis: Definition, prevalence, etiology, and management-A scoping review

BACKGROUND

For persons with multiple sclerosis (pwMS), exercise is known to be safe and effective at treating several symptoms and it may even be disease-modifying. However, exercise can trigger heat intolerance, exercise-induced heat sensitivity (EIHS), which may cause some pwMS to refrain from exercise. No review has yet summarized the existing knowledge on EIHS in pwMS. Therefore, the purpose of the present review was to clarify the terminology, summarize both the prevalence of EIHS and the current knowledge of underlying mechanisms, and provide an overview of existing treatment options and clinical management of EIHS in pwMS.

METHODS

A scoping review was performed.

RESULTS

As no clear definition could be identified in the literature, we propose a definition of EIHS. Aspects related to EIHS are reported in 29-80 % of all pwMS. The mechanisms underlying EIHS are not well understood but seem to include axon demyelination, CNS lesions, abnormal sudomotor function and sweating, abnormal afferent thermosensory function, disease stability, and abnormal neuropsychological responses. The severity of EIHS depends on the applied exercise modality, intensity, and format, and can be further reduced when applying different cooling interventions or garments before and/or during exercise.

CONCLUSION

EIHS appears frequently in pwMS, but the underlying mechanisms are still only sparsely understood. EIHS severity depends on exercise-related factors and can be reduced by cooling interventions.

Using the Knowledge to Action framework to improve housing and support for people with Multiple Sclerosis

Background People with Multiple Sclerosis (MS) have unique housing and support needs that are essential for maintaining independence at home; however, there is limited research to guide the design of community living options for this population. The aim of this study was to examine housing and support needs and preferences of people with MS with the intention to inform the planning of a co-designed intervention based on the study's findings. Methods Using the Knowledge to Action (KTA) framework, quantitative (n =79) and qualitative (n =6) data from people with MS were extracted and integrated from projects completed by the research team that explored the housing and support needs and preferences of people with disability. Results were synthesised and presented to a reference group for validation, contextualisation, and adaptation to the Australian context. Results High physical support needs were common across participants. People most commonly required home modifications to improve accessibility, such as ramps, equipment such as heating and cooling, and assistive technology. Many people required more than 8 hours per day of paid support. Moving into individualised housing facilitated independence and community reintegration. People reported gaps between what they wanted from support workers and what they received, citing individual and systemic barriers. Conclusion People with MS have support needs that require proactive and responsive funding arrangements, housing design and support provision. In line with KTA principles, findings will inform the planning of a co-designed intervention that involves people with lived experience of MS and other stakeholders to influence policy and improve home and living outcomes for this population.

Evidence of heat sensitivity in people with Parkinson's disease

Examining how heat affects people with Parkinson's disease is essential for informing clinical decision-making, safety, well-being, and healthcare planning. While there is evidence that the neuropathology associated with Parkinson's disease affects thermoregulatory mechanisms, little attention has been given to the association of heat sensitivity to worsening symptoms and restricted daily activities in people with this progressive disease. Using a cross-sectional study design, we examined the experiences of people diagnosed with Parkinson's disease in the heat. Two-hundred and forty-seven people completed an online survey (age: 66.0 ± 9.2 years; sex: male = 102 (41.3%), female = 145 (58.7%)), of which 195 (78.9%) reported becoming more sensitive to heat with Parkinson's disease. Motor and nonmotor symptoms worsened with heat in 182 (73.7%) and 203 (82.2%) respondents, respectively. The most commonly reported symptoms to worsen included walking difficulties, balance impairment, stiffness, tremor, fatigue, sleep disturbances, excess sweating, difficulty concentrating, and light-headedness when standing. Concerningly, over half indicated an inability to work effectively in the heat, and nearly half reported that heat impacted their ability to perform household tasks and social activities. Overall, heat sensitivity was common in people with Parkinson's disease and had a significant impact on symptomology, day-to-day activities and quality of life.

Brain connectivity changes underlying depression and fatigue in relapsing-remitting multiple sclerosis: A systematic review

Multiple Sclerosis (MS) is an autoimmune disease affecting the central nervous system, characterised by neuroinflammation and neurodegeneration. Fatigue and depression are common, debilitating, and intertwined symptoms in people with relapsing-remitting MS (pwRRMS). An increased understanding of brain changes and mechanisms underlying fatigue and depression in RRMS could lead to more effective interventions and enhancement of quality of life. To elucidate the relationship between depression and fatigue and brain connectivity in pwRRMS we conducted a systematic review. Searched databases were PubMed, Web-of-Science and Scopus. Inclusion criteria were: studied participants with RRMS (n ≥ 20; ≥ 18 years old) and differentiated between MS subtypes; published between 2001-01-01 and 2023-01-18; used fatigue and depression assessments validated for MS; included brain structural, functional magnetic resonance imaging (fMRI) or diffusion MRI (dMRI). Sixty studies met the criteria: 18 dMRI (15 fatigue, 5 depression) and 22 fMRI (20 fatigue, 5 depression) studies. The literature was heterogeneous; half of studies reported no correlation between brain connectivity measures and fatigue or depression. Positive findings showed that abnormal cortico-limbic structural and functional connectivity was associated with depression. Fatigue was linked to connectivity measures in cortico-thalamic-basal-ganglial networks. Additionally, both depression and fatigue were related to altered cingulum structural connectivity, and functional connectivity involving thalamus, cerebellum, frontal lobe, ventral tegmental area, striatum, default mode and attention networks, and supramarginal, precentral, and postcentral gyri. Qualitative analysis suggests structural and functional connectivity changes, possibly due to axonal and/or myelin loss, in the cortico-thalamic-basal-ganglial and cortico-limbic network may underlie fatigue and depression in pwRRMS, respectively, but the overall results were inconclusive, possibly explained by heterogeneity and limited number of studies. This highlights the need for further studies including advanced MRI to detect more subtle brain changes in association with depression and fatigue. Future studies using optimised imaging protocols and validated depression and fatigue measures are required to clarify the substrates underlying these symptoms in pwRRMS.

Whole-Body Cryostimulation in Multiple Sclerosis: A Scoping Review

Multiple sclerosis (MS) is the most common cause of non-traumatic long-term disability in young adults. Whole-body cryostimulation (WBC) is a cold-based physical therapy known to induce physiological exercise-mimicking changes in the cardiovascular, neuromuscular, immune, and endocrine systems and to influence functional and psychological parameters by exposing the human body to cryogenic temperatures (≤-110 °C) for 2-3 min. The purpose of this scoping review is to present an overall view on the potential role of WBC as an adjuvant therapy in the treatment of MS. PubMed, ScienceDirect, Embase, and Web of Science were searched up to 30 November 2023, and a total of 13 articles were included. WBC may have beneficial antioxidant effects as a short-term adjuvant treatment in MS. There were no significant changes in antioxidant enzymes, nitric oxide levels, metalloproteinase levels, blood counts, rheology, and biochemistry. WBC can lead to a reduction in fatigue and an improvement in functional status, with a significant effect on both mental and physical well-being. There were no reported adverse effects. The results suggest that WBC may complement therapeutic options for patients with MS, as the effects of cryogenic cold stimulation have been shown to activate antioxidant processes and improve functional status, mood, anxiety, and fatigue.

The effect of cooling garments to improve physical function in people with multiple sclerosis: A systematic review and meta-analysis

BACKGROUND

There is strong evidence for the benefits of exercise for people with Multiple Sclerosis (MS), however, up to 80% of people with MS report experiencing exacerbated symptoms with elevated body temperatures. A range of cooling garments to assist people with MS manage symptoms of heat sensitivity have been investigated. Therefore, the aim of this systematic review was to assess the effect of cooling garments to improve physical function in people with MS, and to determine any associated physiological and perceptual responses.

METHOD

A systematic review adhering to the PRISMA guidelines was performed. The eligibility criteria required investigations to have conducted a randomized controlled trial or cross-over study to assess the effect of a cooling garment to improve physical function, or a related physiological or perceptual measure, in people with MS.

RESULTS

Thirteen empirical studies were identified, compromising of acute cross-over designs (61.5%), longitudinal parallel group designs (23.1%) or a combination of both (15.4%). The studies included 384 participants with MS with an expanded disability status scale range of 1-7.5. Garments included liquid-perfused cooling vests/tops/hoods (50.0%), phase-change cooling vests (38.9%), a cooling thigh-cuff (5.6%) and a palm cooling device (5.6%). The cooling garments were effective at improving walking capacity and functional mobility, and some studies demonstrated improvements in muscular strength and balance, but not manual dexterity. The garments also resulted in improved core temperature, skin temperature, thermal sensation and subjective fatigue. Improvements occurred in temperate and warm conditions, and both with and without an exercise stimulus.

DISCUSSION

Cooling garments can improve physical function for people with MS. Since none of the cooling garments caused harm, and no particular cooling garment could be identified as being superior, people with MS should experiment with different cooling garments to determine their preference, and industry should focus on cooling garments that are effective, accessible and user-friendly.

Body temperatures, thermal comfort, and neuropsychological responses to air temperatures ranging between 12°C and 39°C in people with Multiple Sclerosis

The negative effects of thermal stress on Multiple Sclerosis (MS)' symptoms have long been known. However, the underlying mechanisms of MS heat and cold intolerance remain unclear. The aim of this study was to evaluate body temperatures, thermal comfort, and neuropsychological responses to air temperatures between 12 to 39°C in people with MS compared to healthy controls (CTR). Twelve MS (5 males/7 females; age: 48.3±10.8 years; EDSS range: 1-7) and 11 CTR participants (4 males /7 females; age: 47.5±11.3 years) underwent two 50-min trials in a climatic chamber. Air temperature was ramped from 24°C to either 39°C (HEAT) or 12°C (COLD) and we continuously monitored participants' mean skin (T_sk) and rectal temperatures (T_rec), heart rate and mean arterial pressure. We recorded participants' self-reported thermal sensation and comfort, mental and physical fatigue, and we assessed their cognitive performance (information processing). Changes in mean T_sk and T_rec did not differ between MS and CTR neither during HEAT nor COLD. However, at the end of the HEAT trial, 83% of MS participants and 36% of CTR participants reported being "uncomfortable". Furthermore, self-reports of mental and physical fatigue increased significantly in MS but not CTR (p<0.05), during both HEAT and COLD. Information processing was lower in MS vs. CTR (p<0.05); yet this cognitive impairment was not exacerbated by HEAT nor COLD (p>0.05). Our findings indicate that neuropsychological factors (i.e. discomfort and fatigue) could contribute to MS heat and cold intolerance in the absence of deficits in the control of body temperature.

Multiple sclerosis-related heat sensitivity linked to absence of DMT prescription and subjective hand impairment but not autonomic or corticospinal dysfunction

OBJECTIVES

Heat sensitivity (HS) describes a temporary worsening of multiple sclerosis (MS) symptoms with increased body temperature. The pathophysiology may relate to central nervous system conduction deficits and autonomic dysfunction. We conducted deep clinical phenotyping of a cohort of persons with MS to identify predictors of HS.

METHODS

We recruited 59 MS participants with HS or No HS. Participants self-reported symptom severity (Hospital Anxiety and Depression Scale, Multiple Sclerosis Impact Scale, and fatigue visual analog scale) and underwent maximal exercise and transcranial magnetic stimulation testing to characterize autonomic and corticospinal function. We examined associations with HS using binomial logistic regression.

RESULTS

People with HS (36/59) had significantly greater disability, depression, fatigue, and physical and psychological functional effects of MS. They also had significantly lower corticospinal excitability but not conduction. After controlling for disease-modifying therapy (DMT), disability, and disease type, self-reported difficulty using hands in everyday tasks was significantly associated with a large increase in the odds of HS. Autonomic and corticospinal dysfunction were not associated with HS. Lack of DMT use alone was also associated with a large increase in the odds of HS.

DISCUSSION

Following a comprehensive assessment of plausible contributors to HS, HS was most strongly associated with lack of a DMT prescription and self-reported hand dysfunction. Surprisingly, objective measurement of autonomic and corticospinal integrity did not contribute to HS.

Demographic Patterns of MS Patients Using BRISA: An MS-Specific App in Germany

Background: Multiple sclerosis (MS) is a chronic, progressive neurological autoimmune disease impacting quality of life. BRISA is an app designed to help MS patients in Germany track their disease course by symptom-monitoring. This study aimed to understand demographic and health-related characteristics of BRISA users. Methods: Demographic data provided by 2095 users were analyzed to describe characteristics such as sex, age, type of MS, and medication. The distribution of tracked symptoms based on age and time since diagnosis were studied. Furthermore, the covariance of specific symptom pairs was analyzed. Results: BRISA users are predominantly female and between 26 and 55 years old. Relapsing–remitting MS was the most prevalent form of MS. First-line category 1 drugs were most frequently used, followed by high-efficacy category 3 drugs (e.g., monoclonal antibodies). The relative frequencies of use of category 1 and category 2 drugs (e.g., spingosine-1-phosphate-receptor modulators) significantly altered with time since diagnosis. Fatigue, concentration disorders, tingling, forgetfulness, and pain were the top five symptoms affecting users. Conclusion: The results highlight the diversity among MS patients and the need for extensive cohort characterization in the real-world scenario. In-depth analysis could help in identifying novel insights that could aid in disease management.

Voluntary Cooling during Exercise Is Augmented in People with Multiple Sclerosis Who Experience Heat Sensitivity

INTRODUCTION

We tested the hypothesis that people with multiple sclerosis (MS) who experience heat sensitivity voluntarily engage in cool-seeking behavior during exercise to a greater extent than healthy controls.

METHODS

In a 27.0°C ± 0.2°C, 41% ± 2% RH environment, seven participants with relapsing-remitting MS who exhibited heat sensitivity and seven healthy controls completed two randomized trials cycling for 40 min (EX) at 3.5 W·kg-1 metabolic heat production, followed by 30 min recovery (REC). In one trial, participants were restricted from engaging in cooling (CON). In the other trial, participants voluntarily pressed a button to receive 2 min of ~2°C water perfusing a top (COOL). Mean skin and core temperatures and mean skin wettedness were recorded continuously. Total time in cooling provided an index of cool-seeking behavior. RPE, total symptom scores (MS only), and subjective fatigue (MS only) were recorded every 10 min.

RESULTS

Core temperature (+0.5°C ± 0.1°C) and skin wettedness (+0.53 ± 0.02 a.u.) increased but were not different between groups or trials at end exercise (P = 0.196) or end recovery (P = 0.342). Mean skin temperature was reduced in COOL compared with CON at end exercise (P ≤ 0.002), with no differences between groups (P ≥ 0.532). MS spent more total time in cooling during EX (MS, 13 ± 3 min; healthy, 7 ± 4 min; P < 0.001) but not REC (MS, 2 ± 1 min; healthy, 0 ± 1 min; P = 0.496). RPE was greater at end exercise in MS (P = 0.001). Total symptom scores increased during exercise (P = 0.005) but was not different between trials (P = 0.321), whereas subjective fatigue was not attenuated in the cooling trial (P = 0.065).

CONCLUSION

Voluntary cooling is augmented in MS but does not consistently mitigate perceptions of heat-related symptoms or subjective fatigue.

Vitamin D status, proinflammatory cytokines and bone mineral density in Mexican people with multiple sclerosis

BACKGROUND

Vitamin D (VD) has been classically associated with calcium homeostasis and bone mineral density since it has a key role on mineralization and resorption. Immunomodulatory effects have been attributable to VD; low concentrations of VD have been associated with elevation of inflammatory markers. Inflammatory autoimmune diseases, such as multiple sclerosis (MS), a chronic neurodegenerative suffering, whose etiology is still unknown, is directly related to an increase in pro-inflammatory cytokines such as interleukin 17 and interleukin 1β who play an important role in this physiopathology. Nowadays, even though additional studies have linked MS's clinical signs with low VD concentration, there is scarce information of this association in people from regions with sufficient sun exposure. The aim of this study was to evaluate serum VD and cytokine concentrations, and bone density, in Mexican people with MS.

METHODS

Vitamin D (25OHD), interleukin 1β, interleukin 6 and interleukin 17 concentrations of twenty-five volunteers with MS were determined by enzyme-linked immunosorbent assay. Bone mineral density and body composition assessment was performed by dual energy X-Ray absorptiometry.

RESULTS

A mean concentration of 17.3 ± 4.6 ng/ml of 25OHD was obtained, in a range of 5.15 to 25.71 ng/ml; when international advisory bodies thresholds were applied 76% of the participants exhibited some degree of VD inadequacy. Pro-inflammatory markers were detectable among the participants: interleukin 1β in 100%, interleukin 6 in 64%, whereas interleukin 17 was found in 24% of the volunteers. Bone mineral density below the expected for the age was found in 8% of the participants, with lumbar spine as the most affected anatomic region. Non-significant correlations were found between VD and bone mineral density (Z-score) or pro-inflammatory markers.

CONCLUSION

Although non-significant correlations were found between VD and bone mineral density or cytokines, it is important to highlight that an important percentage of our participants exhibited some degree of VD inadequacy, an unknown fact for them, since these are not included in routine clinical evaluations. The low concentrations of VD among this sample regardless of annual UVB sun exposure may suggest the involvement of endogenous and not environmental factors. Further works are needed in order to deepen the physiological causes and effects of VD deficiency in people with MS.

Supervised exercises versus telerehabilitation. Benefits for persons with multiple sclerosis

OBJECTIVES

The purpose of this study was to investigate the effectiveness of structured telerehabilitation on fatigue, health status, quality of life (QoL), and activities of daily living (ADL) and compare the possible effects with structured supervised exercise programs in patients with Multiple Sclerosis.

MATERIALS AND METHODS

This study was a randomized, single-blind trial. Thirty patients with relapsing-remitting Multiple Sclerosis were included in the study and randomly divided into two groups; structured supervised exercise group (Group 1) and telerehabilitation group (Group 2). Group 1 (n = 15) completed a 12 week structured supervised exercise program. Group 2 (n = 15) completed a 12 week structured home-based exercise program. Patients were evaluated with functional independence measure (FIM), first section of Nottingham Health Profile (NHP-I), fatigue severity scale (FSS), and quality of life scale (QoLS) before and after the intervention.

RESULTS

Significant differences were found in all parameters in both groups after the treatment (p < .05). No significant difference was found between groups regarding FIM-total, FIM-motor, FIM-cognitive, NHP sub-parameters, and QoLS (p > .05). Between-group differences revealed a significant difference in FSS and NHP total in favor of Group 1 (p < .05).

CONCLUSION

A structured home-based exercise program can be an alternative to supervised exercises with no side effects in patients with multiple sclerosis. Home-based rehabilitation exercises that are checked and controlled through telerehabilitation can help patients improve their health-related QoL and ADL. However, supervised exercises can be more beneficial regarding the fatigue and health profile compared to the home-based exercises.

Brain Temperature Influences Intracranial Pressure and Cerebral Perfusion Pressure After Traumatic Brain Injury: A CENTER-TBI Study

Background

After traumatic brain injury (TBI), fever is frequent. Brain temperature (BT), which is directly linked to body temperature, may influence brain physiology. Increased body and/or BT may cause secondary brain damage, with deleterious effects on intracranial pressure (ICP), cerebral perfusion pressure (CPP), and outcome.

Methods

Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI), a prospective multicenter longitudinal study on TBI in Europe and Israel, includes a high resolution cohort of patients with data sampled at a high frequency (from 100 to 500 Hz). In this study, simultaneous BT, ICP, and CPP recordings were investigated. A mixed-effects linear model was used to examine the association between different BT levels and ICP. We additionally focused on changes in ICP and CPP during the episodes of BT changes (Δ BT ≥ 0.5 °C lasting from 15 min to 3 h) up or downward. The significance of ICP and CPP variations was estimated with the paired samples Wilcoxon test (also known as Wilcoxon signed-rank test).

Results

Twenty-one patients with 2,435 h of simultaneous BT and ICP monitoring were studied. All patients reached a BT of 38 °C and experienced at least one episode of ICP above 20 mm Hg. The linear mixed-effects model revealed an association between BT above 37.5 °C and higher ICP levels that was not confirmed for lower BT. We identified 149 episodes of BT changes. During BT elevations (n = 79) ICP increased, whereas CPP was reduced; opposite ICP and CPP variations occurred during episodes of BT reduction (n = 70). All these changes were of moderate clinical relevance (increase of ICP of 4.5 and CPP decrease of 7.5 mm Hg for BT rise, and ICP reduction of 1.7 and CPP elevation of 3.7 mm Hg during BT defervescence), even if statistically significant (p < 0.0001). It has to be noted, however, that a number of therapeutic interventions against intracranial hypertension was documented during those episodes.

Conclusions

Patients after TBI usually develop BT > 38 °C soon after the injury. BT may influence brain physiology, as reflected by ICP and CPP. An association between BT exceeding 37.5 °C and a higher ICP was identified but not confirmed for lower BT ranges. The relationship between BT, ICP, and CPP become clearer during rapid temperature changes. During episodes of temperature elevation, BT seems to have a significant impact on ICP and CPP.

Methylome Patterns of Cattle Adaptation to Heat Stress

Heat stress has a detrimental impact on cattle health, welfare and productivity by affecting gene expression, metabolism and immune response, but little is known on the epigenetic mechanisms mediating the effect of temperature at the cellular and organism level. In this study, we investigated genome-wide DNA methylation in blood samples collected from 5 bulls of the heat stress resilient Nellore breed and 5 bulls of the Angus that are more heat stress susceptible, exposed to the sun and high temperature-high humidity during the summer season of the Brazilian South-East region. The methylomes were analyzed during and after the exposure by Reduced Representation Bisulfite Sequencing, which provided genome-wide single-base resolution methylation profiles. Significant methylation changes between stressful and recovery periods were observed in 819 genes. Among these, 351 were only seen in Angus, 366 were specific to Nellore, and 102 showed significant changes in methylation patterns in both breeds. KEGG and Gene Ontology (GO) enrichment analyses showed that responses were breed-specific. Interestingly, in Nellore significant genes and pathways were mainly involved in stress responses and cellular defense and were under methylated during heat stress, whereas in Angus the response was less focused. These preliminary results suggest that heat challenge induces changes in methylation patterns in specific loci, which should be further scrutinized to assess their role in heat tolerance.

Home-based Pilates for symptoms of anxiety, depression and fatigue among persons with multiple sclerosis: An 8-week randomized controlled trial

BACKGROUND

Symptoms of anxiety, depression and fatigue are common comorbidities among persons with multiple sclerosis (PwMS). A previous pilot study supported Pilates as a feasible exercise modality that may improve these outcomes among PwMS.

OBJECTIVE

To quantify the effects of 8 weeks of home-based Pilates on symptoms of anxiety, depression and fatigue among PwMS.

METHODS

A total of 80 PwMS (69 female) were randomized to twice-weekly home-based Pilates guided by a DVD) or wait-list control. Validated questionnaires assessed anxiety, depressive and fatigue symptoms at baseline, weeks 2, 4, 6 and 8. Using intention to treat, repeated measures analysis of covariance (RM-ANCOVA) adjusted for baseline physical activity examined between-group differences across time. Hedges' d quantified the magnitude of differences in outcome change. Sensitivity analyses examined female-only samples.

RESULTS

Group × time interactions were statistically significant for all outcomes (all p ⩽ 0.005). Pilates significantly reduced (all p ⩽ 0.03) depressive symptoms (Quick Inventory of Depressive Symptomatology, d = 0.70; Hospital Anxiety and Depression Scale-Depression, d = 0.74), anxiety (State-Trait Anxiety Inventory, d = 0.30; Hospital Anxiety and Depression Scale-Anxiety, d = 0.49), cognitive (d = 0.44), physical (d = 0.78), psychosocial (d = 0.56) and total fatigue (d = 0.76). Female-only results were materially the same.

CONCLUSION

Home-based Pilates significantly improved anxiety, depressive and fatigue symptoms among PwMS with minimal-to-mild mobility disability, including moderate-to-large, clinically meaningful improvements in depressive and fatigue symptoms.Trial Registration: ClinicalTrials.gov (NCT04120207).

Serum Neurofilament Light Chain Levels in Patients With Presymptomatic Multiple Sclerosis

Importance

Unrecognized demyelinating events often precede the clinical onset of multiple sclerosis (MS). Identification of these events at the time of occurrence would have implications for early diagnosis and the search of causal factors for the disease.

Objective

To assess whether serum neurofilament light chain (sNfL) levels are elevated before the clinical MS onset.

Design, Setting, and Participants

Nested case-control study among US military personnel who have serum samples stored in the US Department of Defense Serum Repository. Serum samples were collected from 2000 to 2011; sNfL assays and data analyses were performed from 2018 to 2019. We selected 60 case patients with MS who either had 2 samples collected before onset (mean follow-up, 6.3 years) or 1 sample collected before and 1 after onset (mean follow-up, 1.3 years), among 245 previously identified case patients. For each case, we randomly selected 1 of 2 previously identified control individuals matched by age, sex, race/ethnicity, and dates of sample collection. The sample size was chosen based on the available funding.

Exposures

Serum NfL concentrations measured using an ultrasensitive single-molecule array assay (Simoa).

Main Outcomes and Measurements

Log-transformed sNfL concentrations in case patients and control individuals compared using conditional logistic regression and linear mixed models.

Results

Mean age at baseline was 27.5 years, and 92 of 120 participants (76.7%) were men. Serum NfL levels were higher in case patients with MS compared with their matched control individuals in samples drawn a median of 6 years (range, 4-10 years) before the clinical onset (median, 16.7 pg/mL; interquartile range [IQR], 12.6-23.1 pg/mL vs 15.2 pg/m; IQR, 10.3-19.9 pg/mL; P = .04). This difference increased with decreasing time to the case clinical onset (estimated coefficient for interaction with time = 0.063; P = .008). A within-person increase in presymptomatic sNfL levels was associated with higher MS risk (rate ratio for ≥5 pg/mL increase, 7.50; 95% CI, 1.72-32.80). The clinical onset was associated with a marked increase in sNfL levels (median, 25.0; IQR, 17.1-41.3 vs 45.1; IQR, 27.0-102.7 pg/mL for presymptomatic and postonset MS samples; P = .009).

Conclusions and Relevance

The levels of sNfL were increased 6 years before the clinical MS onset, indicating that MS may have a prodromal phase lasting several years and that neuroaxonal damage occurs already during this phase.

New Strategies for Rehabilitation and Pharmacological Treatment of Fatigue Syndrome in Multiple Sclerosis

Multiple sclerosis (MS) is the most common autoimmune disease of the central nervous system (CNS), with an inflammatory demyelinating basis and a progressive course. The course of the disease is very diverse and unpredictable. Patients face many problems on a daily basis, such as problems with vision; sensory, balance, and gait disturbances; pain; muscle weakness; spasticity; tremor; urinary and fecal disorders; depression; and rapidly growing fatigue, which significantly influences quality of life among MS patients. Excessive fatigue occurs in most MS patients in all stages of this disease and is named MS-related fatigue. The crucial issue is the lack of effective treatment; therefore, this review focuses not only on the most common treatment methods, but also on additional novel therapies such as whole-body cryotherapy (WBC), functional electrical stimulation (FES), and non-invasive brain stimulation (NIBS). We also highlight the advantages and disadvantages of the most popular clinical scales used to measure fatigue. The entire understanding of the origins of MS-related fatigue may lead to the development of more effective strategies that can improve quality of life among MS patients. A literature search was performed using MEDLINE, EMBASE, and PEDro databases.

Association between diurnal temperature range and emergency department visits for multiple sclerosis: A time-stratified case-crossover study

Although multiple sclerosis (MS) has been the leading cause of neurologically-induced disability in young adults, risk factors for the relapse and acute aggravation of MS remain unclear. A few studies have suggested a possible role of temperature changes on the relapse and acute aggravation of MS. We investigated the association between short-term exposure to wide diurnal temperature ranges (DTRs) and acute exacerbation of MS requiring an emergency department (ED) visit. A total of 1265 patients visited EDs for acute aggravation of MS as the primary disease in Seoul between 2008 and 2014 from the national emergency database. We conducted a conditional logistic regression analysis of the time-stratified case-crossover design to compare DTRs on the ED visit days for MS and those on control days matched according to the day of the week, month, and year. We examined possible associations with other temperature-related variables (ambient temperature, between-day temperature change, and sunlight hours). Short-term exposure to wide DTRs immediately increased the risk of ED visits for MS. Especially, 2-day average (lag0-1) DTR levels on the day of and one day prior to ED visits exhibited the strongest association (an 8.81% [95% CI: 3.46%-14.44%] change in the odds ratio per 1 °C increase in the DTR). Other temperature-related variables were not associated with MS aggravation. Our results suggest that exposure to wider DTR may increase the risk of acute exacerbation of MS. Given the increasing societal burden of MS and the increasing temperature variability due to climate change, further studies are required.

Shedding light on the link between early life sun exposure and risk of multiple sclerosis: results from the EnvIMS Study

BACKGROUND

Lower levels of sun exposure in childhood have been suggested to be associated with increased risk of multiple sclerosis (MS). In this paper we extend previous work, using two novel analytical strategies.

METHODS

Data collected in the Environmental risk factors In MS (EnvIMS) study, a case-control study with MS cases and population-based controls from Canada, Italy and Norway, were used. Participants reported on sun exposure behaviours for 5-year age intervals from birth; we focused on the first three age intervals (≤15 years). We compared two life course epidemiology conceptual models, the critical period and the accumulation model. We also used latent class analysis to estimate MS risk for different latent sun exposure behaviour groups.

RESULTS

The analyses included 2251 cases and 4028 controls. The accumulation model was found to be the best model, which demonstrated a nearly 50% increased risk of MS comparing lowest reported summer sun exposure with highest [risk ratio (RR) = 1.47 (1.24, 1.74)]. The latent sun exposure behaviour group, characterized by low sun exposure during summer and winter and high sun protection use, had the highest risk of MS; a 76% increased risk as compared with the group with high sun exposure and low sun protection use [RR = 1.76 (1.27, 2.46)].

CONCLUSIONS

Our analyses provide novel insights into the link between sun exposure and MS. We demonstrate that more time indoors during childhood and early adolescence is linked with MS risk, and that sun protection behaviours in those who spend most time indoors may play a key role in increasing risk.

Thermal behavior alleviates thermal discomfort during steady-state exercise without affecting whole body heat loss

We tested the hypothesis that thermal behavior resulting in reductions in mean skin temperature alleviates thermal discomfort and mitigates the rise in core temperature during light-intensity exercise. In a 27 ± 0°C, 48 ± 6% relative humidity environment, 12 healthy subjects (6 men, 6 women) completed 60 min of recumbent cycling. In both trials, subjects wore a water-perfused suit top continually perfusing 34 ± 0°C water. In the behavior trial, subjects maintained their upper body thermally comfortable by pressing a button to perfuse cool water (2.2 ± 0.5°C) through the top for 2 min per button press. Metabolic heat production (control: 404 ± 52 W, behavior: 397 ± 65 W; P = 0.44) was similar between trials. Mean skin temperature was reduced in the behavior trial (by -2.1 ± 1.8°C, P < 0.01) because of voluntary reductions in water-perfused top temperature (P < 0.01). Whole body (P = 0.02) and local sweat rates were lower in the behavior trial (P ≤ 0.05). Absolute core temperature was similar (P ≥ 0.30); however, the change in core temperature was greater in the behavior trial after 40 min of exercise (P ≤ 0.03). Partitional calorimetry did not reveal any differences in cumulative heat storage (control: 554 ± 229, behavior: 544 ± 283 kJ; P = 0.90). Thermal behavior alleviated whole body thermal discomfort during exercise (by -1.17 ± 0.40 arbitrary units, P < 0.01). Despite lower evaporative cooling in the behavior trial, similar heat loss was achieved by voluntarily employing convective cooling. Therefore, thermal behavior resulting in large reductions in skin temperature is effective at alleviating thermal discomfort during exercise without affecting whole body heat loss.NEW & NOTEWORTHY This study aimed to determine the effectiveness of thermal behavior in maintaining thermal comfort during exercise by allowing subjects to voluntarily cool their torso and upper limbs with 2°C water throughout a light-intensity exercise protocol. We show that voluntary cooling of the upper body alleviates thermal discomfort while maintaining heat balance through convective rather than evaporative means of heat loss.

Manufacturing custom-contoured wheelchair seating: A state-of-the-art review

BACKGROUND

Custom-contoured wheelchair seating lowers risk of pressure injury and postural deterioration while custom-contoured wheelchair seating lowers risk of pressure injury and postural deterioration while increasing the stability and functional activity of the wheelchair occupant. Producing custom-contoured seating systems has historically been a labour-intensive process custom-contoured seating systems is historically labour-intensive.

OBJECTIVES

Evaluate the strengths and limitations of current manufacturing processes for custom-contoured wheelchair seating to suggest potential future manufacturing processes.

STUDY DESIGN

Literature review of the state of the art.

METHODS

Research conducted through a literature review focused on the performance of different types of custom-contoured wheelchair seating products and processes over the last 40 years. Recent literature in orthotics and prosthetics was also consulted to assess future trends in seating.

RESULTS

There are five main manufacturing processes currently used to produce custom-contoured wheelchair seating systems. No single process is yet suitable for all wheelchair users, but many manufacturers are transitioning to computer numerical controlled (CNC) milling to reduce manual labour. Adjustable micro-modular seating and moulded seat insert manufacturing are also prevalent and offer alternative seating to soft foam carving.

CONCLUSION

There is a need in the custom wheelchair seating sector for processes that are fast, cost-effective, produce little to no material waste, and that can effectively maintain a comfortable seating micro-climate. Additive manufacturing may meet these criteria, but further evaluation is required.

CLINICAL RELEVANCE

This review suggests that the custom-contoured wheelchair seating manufacturers are moving away from labour-intensive processes towards digital techniques, like CNC foam milling. Additive manufacturing is a potential new process that may reduce overall costs, the lead time in preparing seats and has the potential to better manage the seating micro-climate.

RebiQoL: A randomized trial of telemedicine patient support program for health-related quality of life and adherence in people with MS treated with Rebif

RebiQoL was a phase IV multicenter randomized study to assess the impact of a telemedicine patient support program (MSP) on health-related quality of life (HRQoL) in patients with relapsing-remitting MS (RRMS) being administered with Rebif with the RebiSmart device. The primary endpoint was to assess the impact of MSP compared to patients only receiving technical support for RebiSmart on HRQoL at 12 months, using the psychological part of Multiple Sclerosis Impact Scale (MSIS-29), in patients administered with Rebif. A total of 97 patients diagnosed with RRMS were screened for participation in the study of which 3 patients did not fulfill the eligibility criteria and 1 patient withdrew consent. Of the 93 randomized patients, 46 were randomized to MSP and 47 to Technical support only. The demographic characteristics of the patients were well-balanced in the two arms. There were no statistical differences (linear mixed model) in any of the primary (difference of 0.48, 95% CI: -8.30–9.25, p = 0.91) or secondary outcomes (p>0.05). Although the study was slightly underpowered, there was a trend towards better adherence in the MSP group (OR 3.5, 95% CI 0.85–14.40, p = 0.08) although not statistically significant. No unexpected adverse events occurred. This study did not show a statistically significant effect of the particular form of teleintervention used in this study on HRQoL as compared to pure technical support, for MS patients already receiving Rebif with the RebiSmart device.

Trial Registration: ClinicalTrials.gov: NCT01791244.

Association of acute stress with multiple sclerosis onset and relapse in Saudi Arabia

Objectives:

To determine if there is a relationship between acute stress and either the onset or relapse of multiple sclerosis (MS) and to discover how different types of acute stressors may be involved.

Methods:

This study was carried out in Saudi Arabia between September 2017 and June 2018 and involved King Fahad University Hospital in Eastern province, Arfa Multiple Sclerosis Society in the Central and Western province of Saudi Arabia. A cross-sectional descriptive study was performed using an Arabic self-constructed questionnaire consisted of 4 sections: 1) demographic data and time of diagnosis; 2) emotional/psychological stressors; 3) environmental/physical stressors; and 4) 4 specific stressors measuring their effect on the severity and recurrence of attacks.

Results:

A total of 370 patients participated in the study. Almost half of patients reported no effect of family problems on their disease, whereas the other reported that family problems have an impact on the onset or relapse of the disease. Majority of patients reported that work and social life stressors affect the recurrence of attacks. Cold weather showed no effect on MS; however, hot weather and physical activity increased the number of attacks. Continuous thinking about social stress and problems, mood swings, and sleep deprivation showed an impact on the severity and recurrence of attacks. Financial problems showed no effect.

Conclusion:

Study indicates that an association exists between acute stress and relapse in MS but not the disease onset.

Impact of pre-cooling therapy on the physical performance and functional capacity of multiple sclerosis patients: A systematic review

Patients with multiple sclerosis experience many complications that gradually lead them to comorbidity and disability. Exercise could prevent and ameliorate the symptoms that comorbidity or inactivity generate. However, until recently it was suggested that multiple sclerosis patients should not participate in exercise training programs because these patients are characterized by thermoregulatory failure and the heat stress due to physical work could exacerbate the disease symptoms. Furthermore, taken into account that 60-80% of the multiple sclerosis patients present adverse clinical symptoms when their body temperature is increased (not only due to physical working but even when immerse in hot water or by exposure to infrared lamps or to the sun), the need for the development of treatment strategies to overcome the thermoregulatory problem in these patients is crucial. Given that pre-cooling has been proposed as an effective method, the aim of this systematic review is to discuss the current knowledge for the effects of cooling therapy on the functional capacity of multiple sclerosis patients. The relevant literature includes many articles, but only a handful of studies published thus far have used a cooling intervention in multiple sclerosis patients and have examined the effects of pre-cooling on functional capacity. These studies used active cooling methods, namely garments or other material that are cooled by circulating liquid through a tube, as well as passive, cooling methods. Passive cooling methods include passive cooling garments or other material namely garments that have ice or gel packs inside them. Overall, the results of all the studies analysed in this review demonstrated that pre-cooling therapy can prevent the symptom worsening due to increased body temperature in multiple sclerosis patients without causing adverse effects. Therefore, such strategies could serve as a complimentary therapeutic approach in multiple sclerosis patients.

Burn injury and multiple sclerosis: A retrospective case-control study

OBJECTIVES

The purpose of this study was to determine whether having a previous diagnosis of multiple sclerosis (MS) changed acute care needs in burn-injured patients.

METHODS

This was a retrospective case-control study that included adult (aged ≥18years) patients with an acute burn injury. Control patients were matched with eleven patients with a history of MS at a 4:1 ratio. Outcomes included fluid resuscitation volumes, temperature, heart rate, mean arterial pressure, in-hospital complications, and hospital length of stay (LOS).

RESULTS

There were fifty-five patients included and of those, eleven had a documented history of MS. Fluid resuscitation volumes, temperature, heart rate, and mean arterial pressure were similar between groups during the resuscitation period (p>0.05). LOS was similar between both groups (12, IQR: 2-17 vs. median 16, IQR: 12-21; p=0.090). However, when normalized to % TBSA burn, patients with MS had a significantly higher median LOS/% TBSA burned (1.2, IQR: 0.7-2.0 vs. 2.1, IQR: 1.1-7.1; p=0.031).

CONCLUSIONS

Patients with concurrent burn injuries and MS have a significantly longer LOS/% TBSA burn suggesting that more time is required to heal their wounds. Surprisingly, there were no other significant differences in the after the burn acute phase between these two cohorts.

Temperature sensitivity in multiple sclerosis: An overview of its impact on sensory and cognitive symptoms

Multiple sclerosis (MS) is an autoimmune neurodegenerative disease characterized by demyelination of the central nervous system (CNS). The exact cause of MS is still unknown; yet its incidence and prevalence rates are growing worldwide, making MS a significant public health challenge. The heterogeneous distribution of demyelination within and between MS patients translates in a complex and varied array of autonomic, motor, sensory and cognitive symptoms. Yet a unique aspect of MS is the highly prevalent (60-80%) temperature sensitivity of its sufferers, where neurological symptoms are temporarily exacerbated by environmental- or exercise-induced increases (or decreases) in body temperature. MS temperature sensitivity is primarily driven by temperature-dependent slowing or blocking of neural conduction within the CNS due to changes in internal (core) temperature; yet changes in skin temperature could also contribute to symptom exacerbation (e.g. during sunlight and warm ambient exposure). The impact of temperature sensitivity, and particularly of increases in core temperature, on autonomic (e.g. thermoregulatory/cardiovascular function) and motor symptoms (e.g. fatigue) is well described. However, less attention has been given to how increases (and decreases) in core and skin temperature affect sensory and cognitive symptoms. Furthermore, it remains uncertain whether changes in skin temperature alone could also trigger worsening of symptoms. Here we review the impact of temperature sensitivity on MS sensory and cognitive function and discuss additional factors (e.g. changes in skin temperature) that potentially contribute to temperature-induced worsening of symptoms in the absence of alteration in core temperature.

Perceived cognitive deficits and depressive symptoms in patients with multiple sclerosis: Perceived stress and sleep quality as mediators

Multiple Sclerosis (MS), an autoimmune disorder marked by inflammation of the central nervous system, is associated with a myriad of symptoms. Individuals with MS are more likely to experience depressive symptoms, perhaps due to perceived cognitive impairments. Thus, we aimed to explore perceived stress and sleep deficits as potential mediators of the association between perceived cognitive deficits and depressive symptoms. We recruited a sample of 77 MS participants from an outpatient, university-based MS clinic in the United States. Participants ranged in age between 30 and 75 years old (M = 51.12; SD = 9.6), with more females than males (83% female; n = 64). Participants completed the Perceived Deficits Questionnaire, the Pittsburgh Sleep Quality Index, the Perceived Stress Scale, and the Center for Epidemiological Studies Depression Scale - Revised. Correlation analyses and mediation analyses were conducted with bootstrapping technique. Statistical analyses revealed that higher levels of perceived cognitive deficits were associated with lower quality of sleep, more perceived stress, and higher levels of depressive symptoms. Additionally, both perceived stress and sleep quality served as a significant mediator in the perceived cognitive impairments and depressive symptoms linkage. Our novel findings demonstrate the importance of underlying mechanisms (e.g., sleep quality and perceived stress) in the conceptualization of MS. Perceived stress and sleep quality are potentially modifiable factors, perhaps serving as a target for future treatment, to buffer risk of MS patients developing depression.

Effect of the cooling suit method applied to individuals with multiple sclerosis on fatigue and activities of daily living

AIMS AND OBJECTIVES

To determine the effects of cooling suit on fatigue and activities of daily living of individuals with multiple sclerosis.

BACKGROUND

Fatigue is one of the most common symptoms in people with multiple sclerosis and adversely affects their activities of daily living. Studies evaluating fatigue associated with multiple sclerosis have reported that most of the fatigue cases are related to the increase in body temperature and that cooling therapy is effective in coping with fatigue.

DESIGN

This study used a two sample, control group design.

METHODS

The study sample comprised 75 individuals who met the inclusion criteria. Data were collected with study forms. After the study data were collected, cooling suit treatment was administered to the experimental group. During home visits paid at the fourth and eighth weeks after the intervention, the aforementioned scales were re-administered to the participants in the experimental and control groups.

RESULTS

The analyses performed demonstrated that the severity levels of fatigue experienced by the participants in the experimental group wearing cooling suit decreased. The experimental group also exhibited a significant improvement in the participants' levels of independence in activities of daily living.

CONCLUSIONS

The cooling suit worn by individuals with multiple sclerosis was determined to significantly improve the participants' levels of fatigue and independence in activities of daily living.

RELEVANCE TO CLINICAL PRACTICE

The cooling suit therapy was found to be an effective intervention for the debilitating fatigue suffered by many multiple sclerosis patients, thus significantly improving their level of independence in activities of daily living.

Impaired sweating responses to a passive whole body heat stress in individuals with multiple sclerosis

Multiple sclerosis (MS) is an autoimmune disease that affects the central nervous system (CNS), disrupting autonomic function. The aim of this study was to test the hypothesis that individuals with MS have blunted control of thermoregulatory reflex increases in sweat rate (SR) and cutaneous vasodilation compared with controls during a passive whole body heat stress (WBH). Eighteen individuals with relapsing-remitting MS and 18 healthy controls (Con) participated in the study. Core temperature (T_core), skin temperature, heart rate, arterial blood pressure (10-min intervals), skin blood flow (laser-Doppler flux, LDF), and SR were continuously measured during normothermic baseline (34°C water perfusing a tube-lined suit) and WBH (increased T_core 0.8°C via 48°C water perfusing the suit). Following WBH, local heaters were warmed to 42°C, inducing peak cutaneous vasodilation at the site of LDF collection. Cutaneous vascular conductance (CVC) was calculated as the ratio of LDF to mean arterial pressure and expressed as a percentage of peak achieved during local heating. Individuals with MS had attenuated SR responses to WBH (ΔSR from baseline: Con, 0.65 ± 0.27; MS, 0.42 ± 0.17 mg·cm^-2·min^-1, P = 0.003), whereas Δ%CVC_42C from baseline was similar between groups (Con, 42 ± 16%; MS, 38 ± 12%, P = 0.39). SR responses were blunted as a function of T_core in MS (interaction: group × T_core, P = 0.03), of which differences were evident at ΔT_core 0.7°C and 0.8°C (P < 0.05). No interaction was observed in Δ%CVC_42C Taken together, the findings show MS blunts sweating responses, whereas control of the cutaneous vasculature is preserved, in response to WBH.NEW & NOTEWORTHY This study is the first to assess the reflex control of the thermoregulatory system in individuals living with multiple sclerosis (MS). The novel findings are twofold. First, attenuated increases in sweat rate in subjects with MS compared with healthy controls were observed in response to a moderate increase (0.8°C) in core temperature via passive whole body heat stress. Second, it appears the reflex control of the cutaneous vasculature is preserved in MS.

Increased postural sway in persons with multiple sclerosis during short-term exposure to warm ambient temperatures

BACKGROUND

Multiple sclerosis (MS) is a neurological disease marked by demyelination and axonal loss. Individuals with MS experience increases in clinical signs and symptoms during heat exposure.

OBJECTIVE

To test the hypothesis that moderate heat exposure adversely affects postural sway in individuals with MS.

METHODS

Ten individuals with relapsing-remitting MS (50±8y) and nine controls (47±10y) were examined under a Thermal and a Time Control trial. Following a 30min thermoneutral baseline (25°C, 30% relative humidity (RH)), stand tests randomized with eyes open and closed, were performed. For Thermal, subjects were first exposed to 60min of heating (40°C, 30%RH) followed by 60min of cooling (20°C, 30%RH). For Time Control, subjects remained in a thermoneutral environment throughout. Stand tests were repeated at consistent times in both trials.

RESULTS

No difference in skin and core temperatures between groups were observed for any trial (P>0.05). During heating, postural sway was higher in MS relative to control subjects (eyes open, P=0.03; eyes closed, P=0.011). No differences in postural sway, regardless of eye status, were observed during the Time Control trial for either group (P>0.05).

CONCLUSION

These data demonstrate that exposure to a moderate heating environment increases postural sway in patients with MS.

Temperature dependence of multiple sclerosis mortality rates in the United States

Background:

It is well known that multiple sclerosis (MS) patients are very sensitive to heat events. However, how MS patients respond to the significant temperature difference between the high- and low-latitude regions is not understood.

Objective:

The goal is to identify the primary factor responsible for the fact that MS mortality rates of the United States is more than three times higher in the northern states than in the southern states.

Methods:

Correlation coefficients between the age-adjusted mortality rate of MS as the underlying cause of death and the state average temperature, altitude, latitude, duration of sunshine hours, and solar radiation in the 48 contiguous states were compared.

Results:

MS mortality rates correlate significantly and inversely with temperatures in the 48 states (correlation coefficient r = −0.812 and significance p = 0.00). Durations of sunshine hours and solar radiation do not correlate significantly with MS mortality rates ( r = −0.245, −0.14, and p = 0.101, 0.342, respectively).

Conclusion:

High environmental temperature is the primary reason for the low MS mortality rates and likely the low MS prevalence in low-latitude regions. Implication of the study result is that benefits of long-term heat acclimation through gradual and prolonged exposure to environmental heat for MS patients may be greatly underappreciated.

Effects of vigorous walking exercise on core body temperature and inhibitory control in thermosensitive persons with multiple sclerosis

Aim: Acute, moderate intensity aerobic exercise might improve cognition in multiple sclerosis (MS), but it is unknown if increases in core body temperature (Ctemp) that negates those effects in thermosensitive persons with MS. Materials & methods: Fourteen fully ambulatory, thermosensitive persons with MS completed 20-min bouts of vigorous intensity treadmill walking exercise and seated quiet rest in a randomized, counterbalanced order. Ctemp was measured throughout each experimental condition. Inhibitory control (i.e., an executive function) was measured immediately prior to and following each condition. Results: Ctemp was elevated (˜0.6°C) with vigorous exercise versus quiet rest (p < 0.05). There further were pre-to-post improvements in inhibitory control for vigorous exercise versus quiet rest (ηp 2 = 0.29). Conclusion: Exercise-related increases in Ctemp do not nullify the potential acute exercise benefits on inhibitory control in MS.

Effects of a Short Physical Exercise Intervention on Patients with Multiple Sclerosis (MS)

BACKGROUND

The aim of this prospective randomized controlled trial was to investigate if a short-term endurance or combined endurance/resistance exercise program was sufficient to improve aerobic capacity and maximum force in adult patients (18-65 years) with multiple sclerosis (MS).

METHODS

All patients performed a three-month exercise program consisting of two training sessions per week, lasting 40 min each, with moderate intensity. All patients had a maximum value of 6 (low to moderate disability) on the Expanded Disability Status Scale (EDSS). One group (combined workout group (CWG); 15 females, 4 males) completed a combined endurance/resistance workout (20 min on a bicycle ergometer, followed by 20 min of resistance training), while the other group (endurance workout group (EWG); 13 females, 5 males) completed a 40 min endurance training program. Aerobic capacity was assessed as peak oxygen uptake, ventilatory anaerobic threshold, and workload expressed as Watts. Maximum force of knee and shoulder extensors and flexors was measured using isokinetic testing. Quality of life was assessed with the SF-36 questionnaire, and fatigue was measured using the Modified Fatigue Impact Scale.

RESULTS

Both training groups increased in aerobic capacity and maximum force. EWG, as well as CWG, showed improvement in several subscales of the SF-36 questionnaire and decrease of their fatigue.

CONCLUSION

A short exercise intervention increased both aerobic capacity and maximum force independent of whether endurance or combined endurance/resistance workouts were performed.

Workers with disability: the case of multiple sclerosis

The impact of the multiple sclerosis (MS) on the individual's ability to work is important especially because the onset of the disease occurs mainly between 20 and 30 years of age. This study evaluated different factors associated with job maintenance using a questionnaire that defined what factors are considered obstacle or help in work management. A cross-sectional study of people with MS was carried out in Italy. A total of 1016 individuals with MS were enrolled in the study. Our results showed that negative item related to job maintenance as 'attitudes of other in the workplace' was associated with a lower likelihood of being employed (OR 0.65, 95% CI 0.57-0.76), while 'your attitudes toward work' (OR 1.37, 95% CI 1.19-1.59), 'attitudes of other in the workplace' (OR 1.41, 95% CI 1.17-1.69) and 'personal considerations' (OR 1.54, 95% CI 1.23-1.93), positive items related to job maintenance, were associated with a higher likelihood of being employed. In addition, a poor quality of life and severity disease as well same demographic characteristics (i.e. to be resident in South Italy or in the Islands, living in own original family, have lower educational level) inhibited significantly the job maintenance together with a heavy job and a fixed-term contract. In conclusion, a complex set of variables contribute to the barriers faced by PwMS who are employed suggesting that different stakeholders may play an important role in difficult management of the work for people with MS.

Deimination level and peptidyl arginine deiminase 2 expression are elevated in astrocytes with increased incubation temperature

Astrocytes respond to environmental cues, including changes in temperatures. Increased deimination, observed in many progressive neurological diseases, is thought to be contributed by astrocytes. We determined the level of deimination and expression of peptidyl arginine deiminase 2 (PAD2) in isolated primary astrocytes in response to changes on either side (31°C and 41°C) of the optimal temperature (37°C). We investigated changes in the astrocytes by using a number of established markers and accounted for cell death with the CellTiter-Blue assay. We found increased expression of glial fibrillary acidic protein, ALDH1L1, and J1-31, resulting from increased incubation temperature and increased expression of TSP1, S100β, and AQP4, resulting from decreased incubation temperature vs. optimal temperature, suggesting activation of different biochemical pathways in astrocytes associated with different incubation temperatures. Mass spectrometric analyses support such trends. The PAD2 level was increased only as a result of increased incubation temperature with a commensurate increased level of deimination. Actin cytoskeleton and iso[4]LGE, a lipid peroxidase modification, also showed an increase with higher incubation temperature. Altogether, these results suggest that temperature, as an environmental cue, activates astrocytes in a different manner on either side of the optimal temperature and that increase in deimination is associated only with the higher temperature side of the spectrum.

A predictive model for corticosteroid response in individual patients with MS relapses

OBJECTIVES

To derive a simple predictive model to guide the use of corticosteroids in patients with relapsing remitting MS suffering an acute relapse.

MATERIALS AND METHODS

We analysed individual patient randomised controlled trial data (n=98) using a binary logistic regression model based on age, gender, baseline disability scores [physician-observed: expanded disability status scale (EDSS) and patient reported: multiple sclerosis impact scale 29 (MSIS-29)], and the time intervals between symptom onset or referral and treatment.

RESULTS

Based on two a priori selected cut-off points (improvement in EDSS ≥ 0.5 and ≥ 1.0), we found that variables which predicted better response to corticosteroids after 6 weeks were younger age and lower MSIS-29 physical score at the time of relapse (model fit 71.2% - 73.1%).

CONCLUSIONS

This pilot study suggests two clinical variables which may predict the majority of the response to corticosteroid treatment in patients undergoing an MS relapse. The study is limited in being able to clearly distinguish factors associated with treatment response or spontaneous recovery and needs to be replicated in a larger prospective study.

Clinically significant fatigue: prevalence and associated factors in an international sample of adults with multiple sclerosis recruited via the internet

Background

Fatigue contributes a significant burden of disease for people with multiple sclerosis (PwMS). Modifiable lifestyle factors have been recognized as having a role in a range of morbidity outcomes in PwMS. There is significant potential to prevent and treat fatigue in PwMS by addressing modifiable risk factors.

Objectives

To explore the associations between clinically significant fatigue and demographic factors, clinical factors (health-related quality of life, disability and relapse rate) and modifiable lifestyle, disease-modifying drugs (DMD) and supplement use in a large international sample of PwMS.

Methods

PwMS were recruited to the study via Web 2.0 platforms and completed a comprehensive survey measuring demographic, lifestyle and clinical characteristics, including health-related quality of life, disability, and relapse rate.

Results

Of 2469 participants with confirmed MS, 2138 (86.6%) completed a validated measure of clinically significant fatigue, the Fatigue Severity Scale. Participants were predominantly female from English speaking countries, with relatively high levels of education, and due to recruitment methods may have been highly pro-active about engaging in lifestyle management and self-help. Approximately two thirds of our sample (1402/2138; 65.6% (95% CI 63.7–67.7)) screened positive for clinically significant fatigue. Bivariate associations were present between clinically significant fatigue and several demographic, clinical, lifestyle, and medication variables. After controlling for level of disability and a range of stable socio-demographic variables, we found increased odds of fatigue associated with obesity, DMD use, poor diet, and reduced odds of fatigue with exercise, fish consumption, moderate alcohol use, and supplementation with vitamin D and flaxseed oil.

Conclusion

This study supports strong and significant associations between clinically significant fatigue and modifiable lifestyle factors. Longitudinal follow-up of this sample may help clarify the contribution of reverse causation to our findings. Further research is required to explore these associations including randomized controlled trials of lifestyle interventions that may alleviate fatigue.

Uhthoff's phenomenon in multiple sclerosis and neuromyelitis optica

To evaluate and compare the incidence and clinical features of Uhthoff's phenomenon in Japanese patients with neuromyelitis optica (NMO) and those with multiple sclerosis (MS), we asked 135 consecutive patients with MS and an NMO-related disorder (NMOrd) whether they experienced worse neurological symptoms after an increase in body temperature. Responses were obtained from 54 MS and 37 NMOrd patients. Uhthoff's phenomenon was observed in 26 MS (48.1%) and 20 NMOrd patients (54.1%). Motor and sensory symptoms were more frequent than visual symptoms in both diseases. The incidence of Uhthoff's phenomenon was similar in MS and NMOrd.

The sleepy teenager - diagnostic challenges

The sleepy teenager puts the doctor in a, often tricky, situation where it must be decided if we deal with normal physiology or if we should suspect pathological conditions. What medical investigations are proper to consider? What differential diagnoses should be considered in the first place? And what tools do we actually have? The symptoms and problems that usually are presented at the clinical visit can be both of medical and psychosocial character – and actually they are often a mixture of both. Subsequently, the challenge to investigate the sleepy teenager often includes the examination of a complex behavioral pattern. It is important to train and develop diagnostic skills and to realize that the physiological or pathological conditions that can cause the symptoms may have different explanations. Research in sleep disorders has shown different pathological mechanisms congruent with the variations in the clinical picture. There are probably also different patterns of involved neuronal circuits although common pathways may exist. The whole picture remains to be drawn in this interesting and challenging area.

Thermal and motor behavior in experimental autoimmune encephalitis in Lewis rats

Thermoregulation in patients, who suffer from multiple sclerosis (MS) is impaired and may result in either increases or decreases in body temperature. Disturbances in body temperature correlate with acute relapses, and for this reason, it is an important issue in everyday life of those who suffer from MS. Although rat experimental autoimmune encephalitis (EAE) appeared useful for the examination of current therapies against MS, it has not been thoroughly investigated in terms of body temperature. The purpose of this study was to examine the effect of EAE induction on thermal and motor behavior in the rats. Subcutaneous injection of encephalitogenic emulsion into both pads of hind feet of the Lewis rats provoked symptoms of EAE. Body temperature (T(b)) and motor activity of rats were measured using biotelemetry system. We report a significant increase in body temperature within 24 h prior to the EAE manifestation (12 h average of T(b) for EAE induced animals was higher by 1.07 ± 0.06 °C during day-time and by 0.5 ± 0.05 °C during night time in comparison to the control rats). On the other hand, the onset of EAE symptoms was associated with gradual decrease of body temperature, and during the first night-time T(b) was lower by 1.03 ± 0.08 °C in comparison to the control rats. The inhibition of the motor activity started from the night time, 2 days before EAE onset. On the basis of our data, we concluded that the pattern of body temperature changes after EAE induction may be considered as useful symptom (prodrom) to predict precisely the time of EAE onset. Furthermore, we suggest that EAE in rats may be a suitable model to study mechanism of body temperature alternations observed in MS patients.