The effects of heat stress on physical functioning in persons with multiple sclerosis

Circadian Motor Improvement in MS and Core Body Temperature Dipping

This case report describes a man with multiple sclerosis and insomnia who noticed improved motor function during nocturnal awakenings compared with daytime.

Thoughts on Fatigue in Multiple Sclerosis Patients

Chronic fatigue is a common symptom in people with multiple sclerosis (PwMS) and presents as a reversible motor and cognitive impairment with reduced motivation and a desire to rest. The presentation of fatigue symptomatology in PwMS can be spontaneous or induced by mental or physical activity, temperature and humidity fluctuations, acute infections, and even food ingestion. Even though the exacerbation of fatigue symptomatology due to heat reaction is well established, the role of environmental temperature (ambient temperature and relative humidity) is not yet fully understood, and there is not enough systematic evidence regarding its effect. In this article, we present our opinion (based on the current literature and clinical experience) regarding the role of environmental temperature in the manifestation of fatigue symptomatology in PwMS.

Neuroimaging Correlates of Patient-Reported Outcomes in Multiple Sclerosis

Background

Patient-reported outcomes (PROs) are increasingly associated with concurrent and future impairments in persons with multiple sclerosis (pwMS). The structural and pathological relationships with PROs in pwMS have not been elucidated.

Methods

One hundred and forty-two pwMS and 47 healthy controls (HCs) were scanned using 3T MRI and completed a PRO questionnaire named Lifeware® that outlines the physical and psychosocial abilities. Beck's Depression Inventory (BDI) assessed levels of depression. T1- and T2-lesion volume, volumes of the whole brain (WBV), gray matter (GMV), white matter (WMV) and lateral ventricle (LVV) were derived using JIM and SIENAX software. Additional deep GM (DGMV) and nuclei-specific volumes of the thalamus, caudate, globus pallidus, putamen, and hippocampus were calculated using FIRST. Ordinal regression models adjusted for age and depression and mediation analyses were used.

Results

When compared to HCs, pwMS reported significantly greater limitations in mobility domains, including standing up from low seat (p < 0.001), climbing flight of stairs (p < 0.001), lower limb limitation (p < 0.001), limitations in bladder continence (p = 0.001) and fatigability (p < 0.001). Patient-reported limitations related to lower extremity function were explained by age, BDI, and all DGM nuclei volumes (p < 0.029). No such relationships were seen in the HCs. Fatiguability and the extent of life satisfaction were only related to depression (BDI p < 0.001) and not associated with any MRI-based outcomes. Most relationships between structural pathology and PROs were mediated by BDI scores (p < 0.001). In the pwMS group, there were no significant differences in any MRI-based brain volumes between the levels of reported life satisfaction.

Conclusion

PRO measures of lower extremity limitations were associated with DGM structures and DGM-specific nuclei. These findings promote the relevance of measuring DGM structures as measures directly related to subjective well-being and walking limitations. Depression is a significant mediator of PROs and in particular of life satisfaction.

Climate Change and Physiatry: A Call to Proportional and Prospective Action

ABSTRACT

Through increased temperature-related illness, exposure to wildfire smoke and air pollutants, and more frequent and intense natural disasters, climate change is disproportionately affecting the health of people with disabilities. Although the evidence behind the health effects of climate change is growing, there remain critical research gaps in the physiatric literature that must be addressed. Increased education throughout the medical-education continuum is also needed to prepare physiatrists to address the climate-related health effects impacting their patient populations. Physiatrists and their member organizations should advocate for policies that address climate change with a focus on the unique needs of their patient population and the inclusion of people with disabilities in the policy making process.

Heat Exposure and Multiple Sclerosis-A Regional and Temporal Analysis

Multiple sclerosis (MS) is a neurological disorder that progressively distorts the myelination of axons within the central nervous system (CNS). Increased core body temperature or metabolism as a result of exercise are common causes of short-term exacerbations of neurological symptoms in MS. About 60–80% of patients with MS experience a worsening of their symptoms when exposed to heat. In comparison, less data are available on the relationship between ambient meteorological conditions (e.g., temperature and relative humidity (RH)) and fluctuations in such variables in relation to MS symptoms. Thus, this study examined associations between time-lagged exposure to meteorological conditions and risk of a clinic visit due to MS among US veterans between 2010 and 2013. This study leveraged data from the Veterans Affairs (VA) and National Climactic Data Center (NCDC) for the continental US, partitioned into eight climate zones. We used a case crossover design to assess the risk of a MS clinic visit with respect to several meteorological conditions. Location-specific time-lagged daily (ambient) exposure to temperature, RH, and temperature variations (standard deviation (SD) of temperature) were computed (up to 30 days) for each case (i.e., day of MS visit) and control (a randomly assigned date ± 90–270 days prior to visit). Statistical analyses were conducted to examine independent associations between the selected meteorological conditions and risk of MS visits at the national and regional levels. A total of 533,066 patient visits received a MS diagnosis (International Classifications of Diseases (ICD)-9 code = 340). The Northeast (NE) and Upper Midwest (UMW) regions reported the highest frequency of clinic visits due to MS. Clinic visits were 9% more likely to occur in the spring, summer, and fall months (March–October) than in the winter (OR = 1.089; 95% CI = 1.076–1.103; p < 0.01). In the univariate analyses, the SD of temperature, temperature, and temperature–RH interaction were positively associated with an elevated risk of a MS clinic visit, while the RH was negatively associated with the risk for a clinic visit. In multivariate analyses, the strongest association of a MS clinic visit was observed with the SD of the temperature (OR = 1.012; 95% CI 1.008–1.017; p < 0.01). These associations between MS clinic visits and meteorological conditions varied across climate regions, with the strongest associations being observed in the LMW, UMW, DSW, and NE zones. The SD of the temperature was again the strongest associated predictor when examined regionally. Temperature variations and temperature–RH interactions (a proxy of the heat index) showed significant associations with MS clinic visits. These associations varied across climate regions when examined geographically. Our findings have implications for the management of MS in severe or recurrent cases, especially considering the impending changes in the daily temperature variations and intensity of the heatwaves expected with the intensification of global warming.

Anomalously warm weather and acute care visits in patients with multiple sclerosis: A retrospective study of privately insured individuals in the US

BACKGROUND

As the global climate changes in response to anthropogenic greenhouse gas emissions, weather and temperature are expected to become increasingly variable. Although heat sensitivity is a recognized clinical feature of multiple sclerosis (MS), a chronic demyelinating disorder of the central nervous system, few studies have examined the implications of climate change for patients with this disease.

METHODS AND FINDINGS

We conducted a retrospective cohort study of individuals with MS ages 18-64 years in a nationwide United States patient-level commercial and Medicare Advantage claims database from 2003 to 2017. We defined anomalously warm weather as any month in which local average temperatures exceeded the long-term average by ≥1.5°C. We estimated the association between anomalously warm weather and MS-related inpatient, outpatient, and emergency department visits using generalized log-linear models. From 75,395,334 individuals, we identified 106,225 with MS. The majority were women (76.6%) aged 36-55 years (59.0%). Anomalously warm weather was associated with increased risk for emergency department visits (risk ratio [RR] = 1.043, 95% CI: 1.025-1.063) and inpatient visits (RR = 1.032, 95% CI: 1.010-1.054). There was limited evidence of an association between anomalously warm weather and MS-related outpatient visits (RR = 1.010, 95% CI: 1.005-1.015). Estimates were similar for men and women, strongest among older individuals, and exhibited substantial variation by season, region, and climate zone. Limitations of the present study include the absence of key individual-level measures of socioeconomic position (i.e., race/ethnicity, occupational status, and housing quality) that may determine where individuals live-and therefore the extent of their exposure to anomalously warm weather-as well as their propensity to seek treatment for neurologic symptoms.

CONCLUSIONS

Our findings suggest that as global temperatures rise, individuals with MS may represent a particularly susceptible subpopulation, a finding with implications for both healthcare providers and systems.

Evaluating the Utility of Smartphone-Based Sensor Assessments in Persons With Multiple Sclerosis in the Real-World Using an App (elevateMS): Observational, Prospective Pilot Digital Health Study

Background

Multiple sclerosis (MS) is a chronic neurodegenerative disease. Current monitoring practices predominantly rely on brief and infrequent assessments, which may not be representative of the real-world patient experience. Smartphone technology provides an opportunity to assess people’s daily-lived experience of MS on a frequent, regular basis outside of episodic clinical evaluations.

Objective

The objectives of this study were to evaluate the feasibility and utility of capturing real-world MS-related health data remotely using a smartphone app, “elevateMS,” to investigate the associations between self-reported MS severity and sensor-based active functional tests measurements, and the impact of local weather conditions on disease burden.

Methods

This was a 12-week, observational, digital health study involving 3 cohorts: self-referred participants who reported an MS diagnosis, clinic-referred participants with neurologist-confirmed MS, and participants without MS (controls). Participants downloaded the elevateMS app and completed baseline assessments, including self-reported physical ability (Patient-Determined Disease Steps [PDDS]), as well as longitudinal assessments of quality of life (Quality of Life in Neurological Disorders [Neuro-QoL] Cognitive, Upper Extremity, and Lower Extremity Function) and daily health (MS symptoms, triggers, health, mobility, pain). Participants also completed functional tests (finger-tapping, walk and balance, voice-based Digit Symbol Substitution Test [DSST], and finger-to-nose) as an independent assessment of MS-related cognition and motor activity. Local weather data were collected each time participants completed an active task. Associations between self-reported baseline/longitudinal assessments, functional tests, and weather were evaluated using linear (for cross-sectional data) and mixed-effects (for longitudinal data) regression models.

Results

A total of 660 individuals enrolled in the study; 31 withdrew, 495 had MS (n=359 self-referred, n=136 clinic-referred), and 134 were controls. Participation was highest in clinic-referred versus self-referred participants (median retention: 25.5 vs 7.0 days). The top 5 most common MS symptoms, reported at least once by participants with MS, were fatigue (310/495, 62.6%), weakness (222/495, 44.8%), memory/attention issues (209/495, 42.2%), and difficulty walking (205/495, 41.4%), and the most common triggers were high ambient temperature (259/495, 52.3%), stress (250/495, 50.5%), and late bedtime (221/495, 44.6%). Baseline PDDS was significantly associated with functional test performance in participants with MS (mixed model–based estimate of most significant feature across functional tests [β]: finger-tapping: β=–43.64, P<.001; DSST: β=–5.47, P=.005; walk and balance: β=–.39, P=.001; finger-to-nose: β=.01, P=.01). Longitudinal Neuro-QoL scores were also significantly associated with functional tests (finger-tapping with Upper Extremity Function: β=.40, P<.001; walk and balance with Lower Extremity Function: β=–99.18, P=.02; DSST with Cognitive Function: β=1.60, P=.03). Finally, local temperature was significantly associated with participants’ test performance (finger-tapping: β=–.14, P<.001; DSST: β=–.06, P=.009; finger-to-nose: β=–53.88, P<.001).

Conclusions

The elevateMS study app captured the real-world experience of MS, characterized some MS symptoms, and assessed the impact of environmental factors on symptom severity. Our study provides further evidence that supports smartphone app use to monitor MS with both active assessments and patient-reported measures of disease burden. App-based tracking may provide unique and timely real-world data for clinicians and patients, resulting in improved disease insights and management.

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.

Vigorous cool room treadmill training to improve walking ability in people with multiple sclerosis who use ambulatory assistive devices: a feasibility study

BACKGROUND

Aerobic training has the potential to restore function, stimulate brain repair, and reduce inflammation in people with Multiple Sclerosis (MS). However, disability, fatigue, and heat sensitivity are major barriers to exercise for people with MS. We aimed to determine the feasibility of conducting vigorous harness-supported treadmill training in a room cooled to 16 °C (10 weeks; 3times/week) and examine the longer-term effects on markers of function, brain repair, and inflammation among those using ambulatory aids.

METHODS

Ten participants (9 females) aged 29 to 74 years with an Expanded Disability Status Scale ranging from 6 to 7 underwent training (40 to 65% heart rate reserve) starting at 80% self-selected walking speed. Feasibility of conducting vigorous training was assessed using a checklist, which included attendance rates, number of missed appointments, reasons for not attending, adverse events, safety hazards during training, reasons for dropout, tolerance to training load, subjective reporting of symptom worsening during and after exercise, and physiological responses to exercise. Functional outcomes were assessed before, after, and 3 months after training. Walking ability was measured using Timed 25 Foot Walk test and on an instrumented walkway at both fast and self-selected speeds. Fatigue was measured using fatigue/energy/vitality sub-scale of 36-Item Short-Form (SF-36) Health Survey, Fatigue Severity Scale, modified Fatigue Impact Scale. Aerobic fitness (maximal oxygen consumption) was measured using maximal graded exercise test (GXT). Quality-of-life was measured using SF-36 Health Survey. Serum levels of neurotrophin (brain-derived neurotrophic factor) and cytokine (interleukin-6) were assessed before and after GXT.

RESULTS

Eight of the ten participants completed training (attendance rates ≥ 80%). No adverse events were observed. Fast walking speed (cm/s), gait quality (double-support (%)) while walking at self-selected speed, fatigue (modified Fatigue Impact Scale), fitness (maximal workload achieved during GXT), and quality-of-life (physical functioning sub-scale of SF-36) improved significantly after training, and improvements were sustained after 3-months. Improvements in fitness (maximal respiratory exchange ratio and maximal oxygen consumption during GXT) were associated with increased brain-derived neurotrophic factor and decreased interleukin-6.

CONCLUSION

Vigorous cool room training is feasible and can potentially improve walking, fatigue, fitness, and quality-of-life among people with moderate to severe MS-related disability.

TRIAL REGISTRATION

The study was approved by the Newfoundland and Labrador Health Research Ethics Board (reference number: 2018.088) on 11/07/2018 prior to the enrollment of first participant (retrospectively registered at ClinicalTrials.gov: NCT04066972. Registered on 26 August 2019.

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.

Power Relative to Body Mass Best Predicts Change in Core Temperature During Exercise-Heat Stress

Gibson, OR, Willmott, AGB, James, CA, Hayes, M, and Maxwell, NS. Power relative to body mass best predicts change in core temperature during exercise-heat stress. J Strength Cond Res 31(2): 403-414, 2017-Controlling internal temperature is crucial when prescribing exercise-heat stress, particularly during interventions designed to induce thermoregulatory adaptations. This study aimed to determine the relationship between the rate of rectal temperature (Trec) increase, and various methods for prescribing exercise-heat stress, to identify the most efficient method of prescribing isothermic heat acclimation (HA) training. Thirty-five men cycled in hot conditions (40° C, 39% R.H.) for 29 ± 2 minutes. Subjects exercised at 60 ± 9% V[Combining Dot Above]O2peak, with methods for prescribing exercise retrospectively observed for each participant. Pearson product moment correlations were calculated for each prescriptive variable against the rate of change in Trec (° C·h), with stepwise multiple regressions performed on statistically significant variables (p ≤ 0.05). Linear regression identified the predicted intensity required to increase Trec by 1.0-2.0° C between 20- and 45-minute periods and the duration taken to increase Trec by 1.5° C in response to incremental intensities to guide prescription. Significant (p ≤ 0.05) relationships with the rate of change in Trec were observed for prescriptions based on relative power (W·kg; r = 0.764), power (%Powermax; r = 0.679), rating of perceived exertion (RPE) (r = 0.577), V[Combining Dot Above]O2 (%V[Combining Dot Above]O2peak; r = 0.562), heart rate (HR) (%HRmax; r = 0.534), and thermal sensation (r = 0.311). Stepwise multiple regressions observed relative power and RPE as variables to improve the model (r = 0.791), with no improvement after inclusion of any anthropometric variable. Prescription of exercise under heat stress using power (W·kg or %Powermax) has the strongest relationship with the rate of change in Trec with no additional requirement to correct for body composition within a normal range. Practitioners should therefore prescribe exercise intensity using relative power during isothermic HA training to increase Trec efficiently and maximize adaptation.

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.

Whole-body cryostimulation (cryotherapy) provides benefits for fatigue and functional status in multiple sclerosis patients. A case-control study

OBJECTIVES

To study the effects of whole-body cryostimulation (WBC) on fatigue and functional status in multiple sclerosis (MS) patients with different levels of fatigue.

SUBJECTS AND METHODS

Two groups of 24 MS patients with fatigue were studied. At the beginning of the study, the first group presented a Fatigue Severity Scale (FSS) score between 38 and 42 (low-fatigue (LF) group), and the second group had an FSS score between 48 and 52 (high-fatigue (HF) group). Both groups were matched for age and sex. All patients were exposed to 10.3-min session of WBC (one exposure per day at -110°C or lower). Functional status was assessed before and after the series of WBC exposures using the Rivermead Motor Assessment (RMA), the Multiple Sclerosis Impact Scale (MSIS-29), and the Expanded Disability Status Scale (EDSS). The RMA was estimated in three sections: gross function (RMA1), leg and trunk (RMA2), and arm (RMA3). MSIS-29 consists of two subscales assessing the physical (MSIS-29-PHYS) and psychological (MSIS-29-PSYCH) status.

RESULTS

In both groups, the WBC sessions induced a significant improvement in the functional status and in the feeling of fatigue. However, the changes observed in HF patients were significantly greater than those observed in LF patients, especially in the MSIS-29-PHYS, MSIS-29-PSYCH, RMA1, and RMA3. The changes observed in the EDSS, RMA2, and FSS were similar in both groups.

CONCLUSIONS

WBC appears to be effective in improving functional status and the feeling of fatigue in patients with MS and especially in those who are the most fatigued.

Hsp72 and Hsp90α mRNA transcription is characterised by large, sustained changes in core temperature during heat acclimation

Increased intracellular heat shock protein-72 (Hsp72) and heat shock protein-90α (Hsp90α) have been implicated as important components of acquired thermotolerance, providing cytoprotection during stress. This experiment determined the physiological responses characterising increases in Hsp72 and Hsp90α mRNA on the first and tenth day of 90-min heat acclimation (in 40.2 °C, 41.0 % relative humidity (RH)) or equivalent normothermic training (in 20 °C, 29 % RH). Pearson's product-moment correlation and stepwise multiple regression were performed to determine relationships between physiological [e.g. (Trec, sweat rate (SR) and heart rate (HR)] and training variables (exercise duration, exercise intensity, work done), and the leukocyte Hsp72 and Hsp90α mRNA responses via reverse transcription quantitative polymerase chain reaction (RT-QPCR) (n = 15). Significant (p < 0.05) correlations existed between increased Hsp72 and Hsp90α mRNA (r = 0.879). Increased core temperature was the most important criteria for gene transcription with ΔTrec (r = 0.714), SR (r = 0.709), Trecfinal45 (r = 0.682), area under the curve where Trec ≥ 38.5 °C (AUC38.5 °C; r = 0.678), peak Trec (r = 0.661), duration Trec ≥ 38.5 °C (r = 0.650) and ΔHR (r = 0.511) each demonstrating a significant (p < 0.05) correlation with the increase in Hsp72 mRNA. The Trec AUC38.5 °C (r = 0.729), ΔTrec (r = 0.691), peak Trec (r = 0.680), Trecfinal45 (r = 0.678), SR (r = 0.660), duration Trec ≥ 38.5 °C (r = 0.629), the rate of change in Trec (r = 0.600) and ΔHR (r = 0.531) were the strongest correlate with the increase in Hsp90α mRNA. Multiple regression improved the model for Hsp90α mRNA only, when Trec AUC38.5 °C and SR were combined. Training variables showed insignificant (p > 0.05) weak (r < 0.300) relationships with Hsp72 and Hsp90α mRNA. Hsp72 and Hsp90α mRNA correlates were comparable on the first and tenth day. When transcription of the related Hsp72 and Hsp90α mRNA is important, protocols should rapidly induce large, prolonged changes in core temperature.

Increasing Physical Activity and Participation in People With Multiple Sclerosis: A Review

Multiple sclerosis (MS) is a chronic progressive disease of the central nervous system (CNS) affecting >2.5 million people worldwide. Damage to neurons in the CNS causes various sensorimotor and cognitive symptoms, such as fatigue, pain, spasticity, memory deficits, and impairment of mobility. Until the late 1990s, it was believed that symptoms of MS would be worsened with physical exertion and people with MS were encouraged to limit physical activity and exertion. Not only has emerging evidence suggested that physical activity, including exercise, is safe for people with MS, there is also evidence that at least some of the disability that occurs after MS is due to secondary deconditioning from the sedentary lifestyle adopted because of the symptoms of MS, not just CNS damage alone. Therefore, not only is physical activity safe, it is also required for maintaining function and health in people with MS. The purpose of this article is to review the unique physical and social barriers to physical activity in people with MS, including those with moderate to severe disability who use a wheelchair or scooter for mobility. We will discuss how existing guidelines for physical activity may not meet the needs of people with MS and present evidence-based considerations for promoting physical activity in people with MS. Ultimately, the goal is to overcome the barriers to physical activity and improve health, participation, and quality of life in people with MS.

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.

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.

The experiences of individuals with Multiple Sclerosis in the Western Cape, South Africa

Background: Multiple Sclerosis (MS) is a debilitating and degenerative lifelong neurological disease that seems to be growing increasingly more prevalent in South Africa.Objectives: The aim of this qualitative study was to explore the personal experiences of individuals with MS in the South African context. The focus of this study was on the challenges faced by individuals with MS, as well as the resources that help them to cope with this debilitating, neurological condition.Method: Thematic analysis was used to explore the semi-structured interviews that were conducted with ten individuals with MS.Results: Several themes emerged that related to the participants’ experiences of living with MS. These themes included several challenges faced by the participants on a daily basis, such as the process of being diagnosed, daily life, invisible illness and medical aid schemes. Numerous resources that help these individuals to cope with MS also emerged from the data analysis and consisted of social support, mobility aids, religion and knowledge about MS.Conclusion: It is evident from the findings of this study that although individuals living with MS, which is a debilitating neurological condition, face several challenges on a daily basis, they often have several resources that help them to cope effectively with this condition. The findings of this study regarding knowledge of the challenges faced and the resources utilised by individuals with MS will hopefully create awareness of the disease and contribute to and inform the design and implementation of interventions for such individuals. Agtergrond: Veelvuldige Sklerose (VS) is ‘n aftakelende en degerenatiewe lewenslange neurologiese toestand wat blyk of dit toenemend meer algemeen in Suid-Afrika voorkom.Objektief: Die doel van hierdie kwalitatiewe studie was om die persoonlike ervarings van individue met VS binne die Suid-Afrikaanse konteks te ondersoek.Die fokus van hierdie studie was op die uitdagings wat individue met VS in die gesig staar, sowel as die hulpbronne wat hulle help met die hantering van hierdie ernstige neurologiese toestand.Metode: Tematiese analise is gebruik om die semi-gestruktureerde onderhoude te ondersoek, wat gevoer is met tien individue met VS.Resultate: Verskeie temas wat verband hou met die deelnemers se ervarings van ‘n lewe met VS het na vore gekom. Hierdie temas het verskeie uitdagingsingesluit wat die deelnemers op ‘n daaglikse basis in die gesig staar, soos die proses om korrek gediagnoseer te word, daaglikse lewe, onsigbare siekte en mediese fonds skemas. ‘n Aantal hulpbronne wat hierdie individue help om VS te hanteer het ook na vore gekom en bestaan uit sosiale ondersteuning, mobiliteit hulpmiddels, geloof en kennis oor VS.Gevolgtrekking: Dit is duidelik uit die bevindinge dat alhoewel individue wat lewe met VS, wat ‘n ernstige neurologiese toestand is, verskeie uitdaging op ‘n daaglikse basis in die gesig staar, hulle beskik oor verskeie hulpbronne wat hulle help om hierdie toestand effektief te hanteer. Die bevindinge van hierdiestudie rakende kennis van die uitdagings wat hierdie individue in die gesig staar en die hulpbronne wat individue met VS gebruik sal hopelik ‘n bewustheid skep en bydra tot die ontwerp en implimentering van intervensies vir sulke individue.

Upper limb assessment in multiple sclerosis: a systematic review of outcome measures and their psychometric properties

OBJECTIVE

To provide an overview of applied upper limb outcome measures in multiple sclerosis (MS) according to the International Classification of Functioning, Disability and Health (ICF) levels and to review their psychometric properties in MS.

DATA SOURCES

PubMed and Web of Knowledge.

STUDY SELECTION

Articles published until June 2013 were selected when written in English, published in the last 25 years, peer reviewed, including >5 persons with MS, and including standardized clinical upper limb outcome measures. Included articles were screened based on title/abstract and full text by 2 independent reviewers. In case of doubt, feedback from a third independent reviewer was obtained. Additionally, references lists were checked for relevant articles. Of the articles, 109 met the selection criteria and were included for data extraction.

DATA EXTRACTION

All reported clinical upper limb outcome measures were extracted from the included studies and classified according to the ICF levels by 2 independent reviewers. In addition, available psychometric properties (reliability, validity, responsiveness) in MS were summarized and discussed.

DATA SYNTHESIS

A diversity of outcome measures assessing impairments on the body functions and structures level (n=33), upper limb capacity (n=11), and performance (n=8) on the activity level were extracted from 109 articles. Hand grip strength and the nine-hole peg test (NHPT) were the most frequently used outcome measures. However, multiple outcome measures are necessary to encapsulate the multidimensional character of the upper limb function. The psychometric properties were insufficiently documented for most of the outcome measures, except for the NHPT.

CONCLUSIONS

The results of this review may help with the selection of appropriate outcome measures and may guide future research regarding the psychometric properties in MS.

Symptomatic treatment and management of multiple sclerosis

The range of symptoms which occur in multiple sclerosis (MS) can have disabling functional consequences for patients and lead to significant reductions in their quality of life. MS symptoms can also interact with each other, making their management challenging. Clinical trials aimed at identifying symptomatic therapies have generally been poorly designed and have tended to be underpowered. Therefore, the evidence base for the management of MS symptoms with pharmacologic therapies is not strong and tends to rely upon open-label studies, case reports, and clinical trials with small numbers of patients and poorly validated clinical outcome measures. Recently, there has been a growing interest in the management of MS symptoms with pharmacologic treatments, and better-designed, randomized, double-blind, controlled trials have been reported. This chapter will describe the evidence base predominantly behind the various pharmacologic approaches to the management of MS symptoms, which in most, if not all, cases, requires multidisciplinary input. Drugs routinely recommended for individual symptoms and new therapies, which are currently in the development pipeline, will be reviewed. More interventional therapies related to symptoms that are refractory to pharmacotherapy will also be discussed, where relevant.

Is a hypothetical melanoma-like neuromelanin the underlying factor essential for the aetiopathogenesis and clinical manifestations of multiple sclerosis?

Background

Multiple sclerosis (MS) has undergone a significant increase in incidence in the industrialised nations over the last 130 years. Changing environmental factors, possibly infections or a lack of or altered timing of them, determine the prevalence of the disease. Although a plethora of aetiological factors, clearly evident in a group of children with MS, appear relevant, there may nevertheless be a single factor essential for the aetiopathogenesis and clinical manifestation of MS.

Description and discussion

This hitherto unknown factor is postulated to be a ‘melanoma-like neuromelanin’ (MLN) dependent on the activation of a gene for syncytin-1. An involvement of MLN could explain the diverse findings in the epidemiology, immunology and pathology of MS, requiring a consideration of a complex infectious background, the human leucocyte antigens, as well as cosmic radiation causing geomagnetic disturbances, vitamin D deficiency, smoking, and lower levels of uric acid.

Summary

In principle, the MLN-based concept is a unifying one, capable of explaining a number of characteristics of the disease. To date, MLN has not been addressed in studies on MS and future work will need to be done on human patients, as there is little or no neuromelanin (the precursor of MLN) in the animals used as experimental models in the study of MS.