Influence of temperature changes on multiple sclerosis: critical review of mechanisms and research potential

Guthrie, Thomas C.; Nelson, Dewey A.

doi:10.1016/0022-510x(94)00248-m

Cited by 181 publications

(113 citation statements)

References 49 publications

Supporting

Mentioning

102

Contrasting

Unclassified

Order By: Relevance

“…In addition to increased fatigue perception, reductions in peak force and faster decline in force were observed in MS patients during HS and are likely due to CNS lesions that are affected by heat, which could lead to recruitment of fewer motor units (conduction block) (11). In controls, there were no heat-related differences in peak force or force decline, which is in contrast to Nybo and Nielsen's work showing that, in healthy individuals, sustained maximal voluntary force declined significantly faster during hyperthermia (19).…”

Section: Discussionmentioning

confidence: 99%

“…It would therefore be expected that thermal stress would produce increases in fatigue perception and exaggerated decrements in task performance in MS patients compared with healthy individuals. However, experimental support for this hypothesis is derived from studies of demyelinated peripheral nerve (11,22).Transcranial magnetic stimulation (TMS) is a noninvasive technique that has been used to study conduction properties of the corticospinal tract and excitability of the motor cortex, as well as CNS changes in response to thermal stress. Comparing motor-evoked potential amplitude (MEP amp ) before and after fatiguing exercise is one method used to examine central fatigue (5).…”

mentioning

confidence: 99%

mentioning

confidence: 99%

“…Individuals with multiple sclerosis (MS), a demyelinating disease of the CNS, commonly experience fatigue that is exacerbated by relatively small (0.5°C) increases in core temperature (11). It has been hypothesized that heat-related fatigue in MS is a form of central fatigue, produced by conduction slowing and/or block in areas of demyelination in the corticospinal system (11,29).…”

mentioning

confidence: 99%

“…It has been hypothesized that heat-related fatigue in MS is a form of central fatigue, produced by conduction slowing and/or block in areas of demyelination in the corticospinal system (11,29). It would therefore be expected that thermal stress would produce increases in fatigue perception and exaggerated decrements in task performance in MS patients compared with healthy individuals.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Effect of passive whole body heating on central conduction and cortical excitability in multiple sclerosis patients and healthy controls

White

VanHaitsma

Vener

et al. 2013

Journal of Applied Physiology

View full text Add to dashboard Cite

White AT, VanHaitsma TA, Vener J, Davis SL. Effect of passive whole body heating on central conduction and cortical excitability in multiple sclerosis patients and healthy controls. J Appl Physiol 114: 1697-1704, 2013. First published April 18, 2013 doi:10.1152/japplphysiol.01119.2012.-Heat stress is associated with increased fatigue perception and decrements in function for individuals with multiple sclerosis (MS). Similarly, healthy individuals experience decrements in exercise performance during hyperthermia. Alterations in central nervous system (CNS) function during hyperthermia include reduced voluntary activation of muscle and increased effort perception. The purpose of this investigation was to test the hypothesis that passive heat exposure in MS patients will produce increased subjective fatigue and impairments in physiological measures of central conduction and cortical excitability compared with healthy individuals. Eleven healthy individuals and 11 MS patients completed a series of transcranial magnetic stimulation studies to examine central conduction and cortical excitability under thermoneutral and heat-stressed (HS) conditions at rest and after a fatiguing thumb abduction task. Passive heat stress resulted in significantly greater fatigue perception and impairments in force production in MS patients. Central motor conduction time was significantly shorter during HS in controls; however, in MS patients normal increases in conduction velocity with increased temperature were not observed centrally. MS patients also exhibited decreased cortical excitability during HS, evidenced by significant increases in resting motor threshold, decreased MEP amplitude, and decreased recruitment curve slope. Both groups exhibited postexercise depression of MEP amplitude, but the magnitude of these decrements was amplified in MS patients during HS. Taken together, these results suggest that CNS pathology in MS patients played a substantial role in reducing cortical excitability during HS. passive hyperthermia; recruitment curve; transcranial magnetic stimulation HIGH INTERNAL TEMPERATURE, ranging from 38.6 to 40.3°C, is associated with voluntary exhaustion during aerobic exercise, despite variations in baseline core temperature, heat storage rates, and final skin temperature (4, 10). Similarly, hyperthermia has been shown to produce motor fatigue, evidenced by decreased voluntary activation during sustained maximal voluntary contractions (MVC) (16,34). Cardiovascular strain during thermal stress contributes to the development of fatigue; however, evidence also suggests that hyperthermia alters central nervous system (CNS) functions, resulting in alterations in voluntary activation of muscle, as well as changes in perception of effort (18,24,33). Little is known about the effects of moderate core temperature increases, in the range between 0.5 to 1.0°C, on CNS function in healthy individuals, although some evidence suggests that decrements in function may begin to appear when core temperatures exceed normal levels (1...

show abstract

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

Effect of passive whole body heating on central conduction and cortical excitability in multiple sclerosis patients and healthy controls

White

VanHaitsma

Vener

et al. 2013

Journal of Applied Physiology

View full text Add to dashboard Cite

show abstract

Premenstrual Multiple Sclerosis Pseudoexacerbations

Wingerchuk¹,

Rodriguez²

2006

Arch Neurol

View full text Add to dashboard Cite

Background: Many women with multiple sclerosis (MS) experience transient neurologic symptom worsening and fatigue in conjunction with the menstrual cycle. Aspirin reduces MS fatigue in some patients. Objective: To describe 3 women with MS who experienced stereotypic, temperature-independent neurologic symptoms and diurnal fatigue in the mid-to-late luteal phase of the menstrual cycle. Aspirin treatment prevented the symptoms.

show abstract

Defining Survival as an Outcome Measure in Amyotrophic Lateral Sclerosis

Gordon¹,

Corcia²,

Lacomblez³

et al. 2009

Arch Neurol

View full text Add to dashboard Cite

To examine how respiratory interventions affect survival as an outcome measure and to define survival rate for trials in amyotrophic lateral sclerosis. Design and Setting: We reviewed the data of 3 phase 3 clinical trials and examined differences in times to death, tracheostomy, and permanent assisted ventilation. We assessed the outcomes with 2 and Fisher exact tests for categorical variables and unpaired, 2-tailed t tests for continuous variables. We used Kaplan-Meier methods to estimate the differences in survival times between interventions. A power analysis generated sample size estimates for different end points. Patients: In all, 2077 patients in 2 phase 3 trials of xaliproden and 400 patients in a phase 3 trial of pentoxifylline. Main Outcome Measures: Death or combined death, tracheostomy, or permanent assisted ventilation. Results: Of 745 deaths, 611 (82.0%) were owing to respiratory failure and 134 (18.0%) to other causes. The use of respiratory interventions across centers ranged from 0% to 6.6% (P=.001) of patients for tracheostomy and 11.1% to 23.1% (P=.05) of patients for noninvasive ventilation. Twelve of 55 patients (21.8%) undergoing tracheostomy had a vital capacity of 50% or more. Mean (SD) survival time was 457.9 (3.1) days using a combined end point and 467.2 (2.9) days with death alone as the outcome (P =.02). An estimated sample size to detect a 10% difference at 18 months between groups was 490 patients per arm for the combined end point and 410 patients for death alone. Conclusions: Tracheostomy and permanent assisted ventilation are not equivalent to death in amyotrophic lateral sclerosis. The use of respiratory interventions differs between centers, leading to variability in combined outcome assessments. The time to the end point can differ significantly depending on its definition, and combining outcomes does not reduce the estimated sample size of a trial. The death rate alone is the least variable and most easily identifiable measure of survival rate in amyotrophic lateral sclerosis.

show abstract

Influence of temperature changes on multiple sclerosis: critical review of mechanisms and research potential

Cited by 181 publications

References 49 publications

Effect of passive whole body heating on central conduction and cortical excitability in multiple sclerosis patients and healthy controls

Effect of passive whole body heating on central conduction and cortical excitability in multiple sclerosis patients and healthy controls

Premenstrual Multiple Sclerosis Pseudoexacerbations

Defining Survival as an Outcome Measure in Amyotrophic Lateral Sclerosis

Contact Info

Product

Resources

About