Meaningful Change Thresholds and Fatigue Severity Points on Patient-Reported Outcomes by the Fatigue Symptoms and Impacts Questionnaire in Patients With Relapsing Multiple Sclerosis

OBJECTIVES

The Fatigue Symptoms and Impacts Questionnaire-Relapsing Multiple Sclerosis (FSIQ-RMS) is a new content-valid, concise, and reliable 20-item patient-reported outcome measure to evaluate the symptoms and impacts of fatigue in patients with relapsing forms of multiple sclerosis. Analyses were performed to derive meaningful change thresholds (MCTs) on patient-reported outcomes as measured by FSIQ-RMS and generate receiver operating characteristic (ROC) curves to determine fatigue severity cut points at baseline and change in severity at post-baseline and supplement the anchor-based MCT results.

METHODS

Analyses were based on data from the OPTIMUM trial (NCT02425644). An anchor-based approach using uncollapsed changes on the Patient Global Impression of Severity at week 108 were used to determine the MCT for only the FSIQ-RMS Symptoms domain; distribution-based MCT estimations were conducted using baseline FSIQ-RMS Impacts scores. ROC curves with calculation of area under the curve were used to identify the best cut point.

RESULTS

Based on the evidence provided by the anchor-based analyses using the Patient Global Impression of Severity as an anchor for the FSIQ-RMS Symptoms domain, meaningful score changes for improvement and deterioration were -6.3 and 6.3, respectively. Meaningful score changes for the FSIQ-RMS Physical, Cognitive/Emotional, and Coping Impacts domains using distribution-based methods were 10.8, 8.4, and 9.8, respectively. These results are supported by the ROC analyses.

CONCLUSIONS

Thresholds to support interpretation of the FSIQ-RMS, such as MCTs, can be used to determine and categorize patients who have experienced a meaningful change in their MS-related fatigue (eg, responder analyses) in future clinical research studies.

The complex relation between visual complaints and decline in visual, visuoperceptual and cognitive functions in people with multiple sclerosis

People with multiple sclerosis (pwMS) report many different visual complaints, but not all of them are well understood. Decline in visual, visuoperceptual and cognitive functions do occur in pwMS, but it is unclear to what extend those help us understand visual complaints. The purpose of this cross-sectional study was to explore the relation between visual complaints and decline in visual, visuoperceptual and cognitive functions, to optimize care for pwMS. Visual, visuoperceptual and cognitive functions of 68 pwMS with visual complaints and 37 pwMS with no or minimal visual complaints were assessed. The frequency of functional decline was compared between the two groups and correlations were calculated between visual complaints and the assessed functions. Decline in several functions occurred more frequently in pwMS with visual complaints. Visual complaints may be an indication of declined visual or cognitive functioning. However, as most correlations were not significant or weak, we cannot infer that visual complaints are directly related to functions. The relationship may be indirect and more complex. Future research could focus on the overarching cognitive capacity that may contribute to visual complaints. Further research into these and other explanations for visual complaints could help us to provide appropriate care for pwMS.

Hemodynamic and neuromuscular basis of reduced exercise capacity in patients with end-stage renal disease

PURPOSE

The present study aimed to characterize the exercise-induced neuromuscular fatigue and its possible links with cerebral and muscular oxygen supply and utilization to provide mechanistic insights into the reduced exercise capacity characterizing patients with end-stage renal disease (ESRD).

METHODS

Thirteen patients with ESRD and thirteen healthy males (CTR group) performed a constant-force sustained isometric contraction at 50% of their maximal voluntary isometric contraction (MVC) until exhaustion. Quadriceps muscle activation during exercise was estimated from vastus lateralis, vastus medialis, and rectus femoris EMG. Central and peripheral fatigue were quantified via changes in pre- to postexercise quadriceps voluntary activation (ΔVA) and quadriceps twitch force (ΔQtw,pot) evoked by supramaximal electrical stimulation, respectively. To assess cerebral and muscular oxygenation, throughout exercise, near-infrared spectroscopy allowed investigation of changes in oxyhemoglobin (∆O2Hb), deoxyhemoglobin (∆HHb), and total hemoglobin (∆THb) in the prefrontal cortex and in the vastus lateralis muscle.

RESULTS

ESRD patients demonstrated lower exercise time to exhaustion than that of CTR (88.8 ± 15.3 s and 119.9 ± 14.6 s, respectively, P < 0.01). Following the exercise, MVC, Qtw,pot, and VA reduction were similar between the groups (P > 0.05). There was no significant difference in muscle oxygenation (∆O2Hb) between the two groups (P > 0.05). Cerebral and muscular blood volume (∆THb) and oxygen extraction (∆HHb) were significantly blunted in the ESRD group (P < 0.05). A significant positive correlation was observed between time to exhaustion and cerebral blood volume (∆THb) in both groups (r2 = 0.64, P < 0.01).

CONCLUSIONS

These findings support cerebral hypoperfusion as a factor contributing to the reduction in exercise capacity characterizing ESRD patients.

Italian adaptation and psychometric validation of the Fatigue Impact Scale (FIS) and its modified versions in adults with multiple sclerosis: a Rasch analysis study

Purpose: Several outcome measures are available to assess the severity of fatigue in people with multiple sclerosis (MS). The aim of this study was to adapt the Italian version of the Fatigue Impact Scale (FIS-40) and its modified versions: a 21-item Modified scale (MFIS-21), its 5-item short version (MFIS-5), and an 8-item version for daily use (DFIS-8) and investigate their measurement properties through classical theory-test (CTT) and Rasch analysis (RA).Methods: 229 Italian-speaking adults with MS were included. Questionnaires were cross-culturally translated and subjected to CTT (i.e. internal consistency through Cronbach's alpha and unidimensionality through confirmatory factor analysis [CFA]) and RA. (i.e. internal construct validity, reliability, and targeting).Results: Internal consistency was high for all scales (>0.850). Final CFAs reported issues in the unidimensionality for all scales except for FIS-40. Baseline RA revealed a misfit for all scales. After adjusting for local dependency, FIS-40, MFIS-21, and MFIS-5 fitted the Rasch model (RM). MFIS-21 and D-FIS-8 required a structural modification, i.e. item deletions to satisfy the RM.Conclusion: The FIS-40, MFIS-21, MFIS-5, and DFIS-8 achieved the fit to the RM after statistical and structural modifications. The fit to the RM allowed for providing ordinal-to-interval measurement conversion tables for all the questionnaires.

Brain FADE syndrome: the final common pathway of chronic inflammation in neurological disease

Importance

While the understanding of inflammation in the pathogenesis of many neurological diseases is now accepted, this special commentary addresses the need to study chronic inflammation in the propagation of cognitive Fog, Asthenia, and Depression Related to Inflammation which we name Brain FADE syndrome. Patients with Brain FADE syndrome fall in the void between neurology and psychiatry because the depression, fatigue, and fog seen in these patients are not idiopathic, but instead due to organic, inflammation involved in neurological disease initiation.

Observations

A review of randomized clinical trials in stroke, multiple sclerosis, Parkinson's disease, COVID, traumatic brain injury, and Alzheimer's disease reveal a paucity of studies with any component of Brain FADE syndrome as a primary endpoint. Furthermore, despite the relatively well-accepted notion that inflammation is a critical driving factor in these disease pathologies, none have connected chronic inflammation to depression, fatigue, or fog despite over half of the patients suffering from them.

Conclusions and relevance

Brain FADE Syndrome is important and prevalent in the neurological diseases we examined. Classical "psychiatric medications" are insufficient to address Brain FADE Syndrome and a novel approach that utilizes sequential targeting of innate and adaptive immune responses should be studied.

Cognitive Reserve Moderates the Effects of Fatigue and Depressive Symptoms in Multiple Sclerosis

To investigate cognitive reserve as a possible moderator in the relationship between fatigue and depressive symptoms in persons with multiple sclerosis (PwMS). Fifty-three PwMS (37 female; mean age, 52.66; mean education, 14.81) completed comprehensive neuropsychological testing and psychosocial questionnaires assessing the perceived effects of fatigue (Fatigue Impact Scale) and depressive symptoms (Beck Depression Inventory-Fast Screen). Cognitive reserve (CR) was operationalized as Fixed CR and Malleable CR. Fixed CR was quantified as the standardized mean of years of education and a vocabulary-based estimate of premorbid intelligence. Malleable CR was quantified as the standardized mean of cognitive exertion, exercise, and socializing items from the Cognitive Health Questionnaire. Regressions on depressive symptoms examining fatigue, both conceptualizations of CR, and their interactions were explored. A Bonferroni correction was used; results were considered significant at an alpha level of p < .01. The interactions between fatigue and both conceptualizations of CR were significant, p = .005 (Fixed CR); p = .004 (Malleable CR). Simple effects tests revealed that fatigue only predicted depressive symptoms in PwMS with low Fixed CR or low Malleable CR (p's < .001), and not in those with high Fixed or high Malleable CR (p > .01). Cognitive reserve moderated the relationship between fatigue and depressive symptoms in PwMS. Specifically, fatigue does not appear to influence depression in PwMS with high cognitive reserve. Having higher cognitive reserve (either Fixed or Malleable) may reduce the likelihood that fatigue will lead to depressive symptoms in MS.

"No association between disease modifying treatment and fatigue in multiple sclerosis"

BACKGROUND

Fatigue affects 60-90% of people with multiple sclerosis (MS). It reduces quality of life and the ability to work. The cause of fatigue in MS remains unknown. Several disease-modifying treatments (DMTs) slow the disease process in relapsing MS by suppressing neuroinflammation. We aimed to investigate if treatment with a DMT is associated with lower rates of fatigue.

METHODS

In this cross-sectional study of the MS population in three counties in Norway, we used the Fatigue Scale for Motor and Cognitive Functions (FSMC) and the Hospital Anxiety and Depression Scale (HADS) to assess patient-reported fatigue, anxiety and depression. Clinical data were retrieved from the electronic patient record system. We categorized DMTs as high-efficacy therapy or moderate-efficacy therapy. High-efficacy drugs included fingolimod, natalizumab, ocrelizumab, rituximab, alemtuzumab, daclizumab, and autologous hematopoietic stem cell transplantation. Moderate-efficacy drugs included interferons, glatiramer acetate, dimethyl fumarate, and teriflunomide. We included persons with relapsing MS only.

RESULTS

Of 1142 patients, 80% had fatigue. Fifty-six percent of the patients were on DMTs (25% on moderate-efficacy treatment and 30% on high-efficacy treatment), 18% had discontinued treatment and 26% had never received any DMT. Sex, level of disability as measured by the Multiple Sclerosis Severity Score, anxiety and depression were independently associated with fatigue. Moderate-efficacy treatment was associated with less fatigue, but not after adjustment for other variables. There was no association between high-efficacy treatment and fatigue.

CONCLUSION

We found no independent relationship between the use of disease-modifying treatment and fatigue in MS.

Multiple Sclerosis and Depression: Translation and Adaptation of the Spanish Version of the Chicago Multiscale Depression Inventory and the Study of Factors Associated with Depressive Symptoms

OBJECTIVE

Depressive disorder occurs in up to 50% of persons with Multiple Sclerosis (PwMS). Accurate assessment of depression in MS is essential in clinical settings because depressive symptomatology can affect the clinical course of the disease.

METHODS

We translated, adapted, and tested the Spanish version of the Chicago Multiscale Depression Inventory (CMDI), a specific test to assess depression in neurological disorders. We compare our results with those obtained with previous versions of the questionnaire (English and Italian). Finally, we also analyze the relationship between the results obtained on the CMDI and demographic, clinical, and cognitive variables.

RESULTS

The results obtained with the Spanish version of the CMDI were similar to those observed in previous published versions. We also observed higher depression scores in PwMS (especially in progressive forms) compared with healthy controls. Moreover, depression symptomatology was related to higher disability and fatigue and worse cognitive performance in PwMS.

CONCLUSIONS

The results support the validity of the CDMI in the Spanish population, as well as the association between depression and other characteristic symptoms of MS. These findings also emphasize the importance of good assessment and multidisciplinary treatment of depression in PwMS.

Moving intra-individual variability (IIV) towards clinical utility: IIV measured using a commercial testing platform

OBJECTIVES

Intra-individual variability (IIV), measured across repeated response times (RT) during continuous psychomotor tasks, is an early marker of cognitive change in the context of neurodegeneration. To advance IIV towards broader application in clinical research, we evaluated IIV from a commercial cognitive testing platform and compared it to the calculation approaches used in experimental cognitive studies.

METHODS

Cognitive assessment was administered in participants with multiple sclerosis (MS) during the baseline of an unrelated study. Cogstate was used for computer-based measures providing three timed-trial tasks measuring simple (Detection; DET) and choice (Identification; IDN) RT and working memory (One-Back; ONB). IIV for each task was automatically output by the program (calculated as a log₁₀-transformed standard deviation or "LSD"). We calculated IIV from the raw RTs using coefficient of variation (CoV), regression-based, and ex-Gaussian methods. The IIV from each calculation was then compared by rank across participants.

RESULTS

A total of n = 120 participants with MS aged 20-72 (Mean ± SD, 48.99 ± 12.09) completed the baseline cognitive measures. For each task, the interclass correlation coefficient was generated. Each ICC showed that LSD, CoV, ex-Gaussian, and regression methods clustered strongly (Average ICC for DET: 0.95 with 95% CI [0.93, 0.96]; Average ICC for IDN: 0.92 with 95% CI [0.88 to 0.93]; Average ICC for ONB: 0.93 with 95% CI [0.90 to 0.94]). Correlational analyses indicated the strongest correlation between LSD and CoV for all tasks (rs ≥ 0.94).

CONCLUSION

The LSD was consistent with research-based methods for IIV calculations. These findings support the use of LSD for the future measurement of IIV for clinical studies.

Neural bases of motor fatigue in multiple sclerosis: A multimodal approach using neuromuscular assessment and TMS-EEG

Motor fatigue is one of the most common symptoms in multiple sclerosis (MS) patients. Previous studies suggested that increased motor fatigue in MS may arise at the central nervous system level. However, the mechanisms underlying central motor fatigue in MS are still unclear. This paper investigated whether central motor fatigue in MS reflects impaired corticospinal transmission or suboptimal primary motor cortex (M1) output (supraspinal fatigue). Furthermore, we sought to identify whether central motor fatigue is associated with abnormal M1 excitability and connectivity within the sensorimotor network. Twenty-two patients affected by relapsing-remitting MS and 15 healthy controls (HCs) performed repeated blocks of contraction at different percentages of maximal voluntary contraction with the right first dorsal interosseus muscle until exhaustion. Peripheral, central, and supraspinal components of motor fatigue were quantified by a neuromuscular assessment based on the superimposed twitch evoked by peripheral nerve and transcranial magnetic stimulation (TMS). Corticospinal transmission, excitability and inhibition during the task were tested by measurement of motor evoked potential (MEP) latency, amplitude, and cortical silent period (CSP). M1 excitability and connectivity was measured by TMS-evoked electroencephalography (EEG) potentials (TEPs) elicited by M1 stimulation before and after the task. Patients completed fewer blocks of contraction and showed higher values of central and supraspinal fatigue than HCs. We found no MEP or CSP differences between MS patients and HCs. Patients showed a post-fatigue increase in TEPs propagation from M1 to the rest of the cortex and in source-reconstructed activity within the sensorimotor network, in contrast to the reduction observed in HCs. Post-fatigue increase in source-reconstructed TEPs correlated with supraspinal fatigue values. To conclude, MS-related motor fatigue is caused by central mechanisms related explicitly to suboptimal M1 output rather than impaired corticospinal transmission. Furthermore, by adopting a TMS-EEG approach, we proved that suboptimal M1 output in MS patients is associated with abnormal task-related modulation of M1 connectivity within the sensorimotor network. Our findings shed new light on the central mechanisms of motor fatigue in MS by highlighting a possible role of abnormal sensorimotor network dynamics. These novel results may point to new therapeutical targets for fatigue in MS.

Relationship between subjective report and objective assessment of neurocognitive functioning in persons with multiple sclerosis

OBJECTIVE

Persons with multiple sclerosis (PwMS) are at increased risk for cognitive dysfunction. Considering the impact and potential ramifications of cognitive dysfunction, it is important that cognition is routinely assessed in PwMS. Thus, it is also important to identify a screener that is accurate and sensitive to MS-related cognitive difficulties, which can inform decisions for more resource-intensive neuropsychological testing. However, research focused on available self-report screeners has been mixed, such as with the Multiple Sclerosis Neuropsychological Screening Questionnaire (MSNQ). This study aims to clarify the relationship between subjective and objective assessment of cognitive functioning in MS by examining domain-specific performance and intraindividual variability (IIV).

METHODS

87 PwMS (F = 65, M = 22) completed a comprehensive neuropsychological battery which included self- and informant-report measures of neurocognitive functioning. Scores were examined in relation to mean performance on five domains of cognitive functioning and two measures of IIV.

RESULTS

The MSNQ-Self was inversely associated with executive function, verbal memory, and visual memory; it was not associated with IIV. The MSNQ-Informant was inversely associated with executive function and verbal memory, and positively associated with one measure of IIV. The MSNQ-Self showed a correlation of moderate effect size with depression (r = .39) while the MSNQ-Informant did not.

CONCLUSIONS

Results suggest that the MSNQ-Self and MSNQ-Informant show similar utility. Our findings also suggest that domains of executive function and memory may be most salient, thus more reflected in subjective reports of cognitive functioning. Future work should further examine the impact of mood disturbance with cognitive performance and IIV.

Fatigue and its relation to general cognition, social cognition and social activity in multiple sclerosis and stroke

INTRODUCTION

The relationship between fatigue and (socio-)cognitive deficits in neurological diseases has sparked increasing research interest in the past years. So far, findings are inconsistent. Most studies focused on general cognitive functioning in specific disorders, particularly cancer or multiple sclerosis (MS).

METHODS

This study aims to examine the relationship between fatigue, social cognition and social activity, also taking into account general cognition, more closely, including a stroke patient group (n = 57), a MS patient group (n = 31) and a healthy control group (n = 20). The participants underwent a comprehensive (socio-)cognitive test battery and completed questionnaires on fatigue and psychopathology which, in addition to fatigue, can also affect (socio-)cognitive performance.

RESULTS

In both MS and stroke patients high fatigue scores were observed. Irrespective of aetiology, patients with high and low fatigue did not differ with regard to general cognition and social cognition. However, high fatigue scores were associated with a reduction of social activities in both patient groups. No other significant relationships were observed between fatigue and (socio-)cognitive measures.

CONCLUSIONS

Future studies ought to further explore the potentially complex nature of fatigue symptoms and their relationship with (socio-)cognitive performance and social activity in neurological populations.

Efficacy of Diet on Fatigue and Quality of Life in Multiple Sclerosis: A Systematic Review and Network Meta-analysis of Randomized Trials

BACKGROUND AND OBJECTIVE

Emerging evidence suggests a role for diet in multiple sclerosis (MS) care; however, owing to methodological issues and heterogeneity of dietary interventions in preliminary trials, the current state of evidence does not support dietary recommendations for MS. The objective of this study was to assess the efficacy of different dietary approaches on MS-related fatigue and quality of life (QoL) through a systematic review of the literature and network meta-analysis (NMA).

METHODS

Electronic database searches were performed in May 2021. Inclusion criteria were (1) randomized trial with a dietary intervention, (2) adults with definitive MS based on McDonald criteria, (3) patient-reported outcomes for fatigue and/or QoL, and (4) minimum intervention period of 4 weeks. For each outcome, standardized mean differences (SMDs) were calculated and included in random effects NMA to determine the pooled effect of each dietary intervention relative to each of the other dietary interventions. The protocol was registered at PROSPERO (CRD42021262648).

RESULTS

Twelve trials comparing 8 dietary interventions (low-fat, Mediterranean, ketogenic, anti-inflammatory, Paleolithic, fasting, calorie restriction, and control [usual diet]), enrolling 608 participants, were included in the primary analysis. The Paleolithic (SMD -1.27; 95% CI -1.81 to -0.74), low-fat (SMD -0.90; 95% CI -1.39 to -0.42), and Mediterranean (SMD -0.89; 95% CI -1.15 to -0.64) diets showed greater reductions in fatigue compared with control. The Paleolithic (SMD 1.01; 95% CI 0.40-1.63) and Mediterranean (SMD 0.47; 95% CI 0.08-0.86) diets showed greater improvements in physical QoL compared with control. For improving mental QoL, the Paleolithic (SMD 0.81; 95% CI 0.26-1.37) and Mediterranean (SMD 0.36; 95% CI 0.06-0.65) diets were more effective compared with control. However, the NutriGRADE credibility of evidence for all direct comparisons is very low because of most of the included trials having high or moderate risk of bias, small sample sizes, and the limited number of studies included in this NMA.

DISCUSSION

Several dietary interventions may reduce MS-related fatigue and improve physical and mental QoL; however, because of the limitations of this NMA, which are driven by the low quality of the included trials, these findings must be confirmed in high-quality, randomized, controlled trials.

Association between improved metabolic risk factors and perceived fatigue during dietary intervention trial in relapsing-remitting multiple sclerosis: A secondary analysis of the WAVES trial

Background

Preliminary dietary intervention trials with the low-saturated fat (Swank) and modified Paleolithic elimination (Wahls) diets have shown favorable effects on fatigue among people with multiple sclerosis (MS); however, their impact on metabolic health is unknown.

Objective

To evaluate the impact of the Swank and Wahls diets on markers of metabolic health and to determine the association and mediation effect between changes in metabolic health and perceived fatigue among people with relapsing-remitting MS (RRMS).

Methods

As part of a randomized parallel-arm trial, vital signs, blood metabolic biomarkers, and the fatigue scale for motor and cognitive functions (FSMC) were collected from participants with relapsing-remitting MS (n = 77) at four study visits spaced 12 weeks apart: (1) run-in, (2) baseline, (3) 12-weeks, and (4) 24-weeks. Participants followed their usual diet at run-in, then were randomized at baseline to either the Swank or Wahls diets and followed for 24 weeks.

Results

Both groups had significant reductions in weight, body mass index (BMI), total cholesterol, and low-density lipoprotein (LDL) at 12- and 24-weeks compared to respective baseline values (p ≤ 0.04 for all). The Swank group also had a significant reduction in high-density lipoprotein (HDL) at 12- and 24-weeks (p = 0.0001 and p = 0.02, respectively), while the Wahls group had significant reductions in diastolic blood pressure (DBP). In addition, both groups had significant reductions in FSMC total perceived fatigue and the motor and cognitive fatigue subscales at 12- and 24-weeks (p ≤ 0.01 for all); however, change in the cognitive subscale was not significant at 12-weeks in the Swank group (p = 0.06). Furthermore, the favorable effects, of both diets, on markers of metabolic health were not associated with and did not mediate the effect of the diets on perceived fatigue (p > 0.05 for all).

Conclusion

Both diets lead to significant reductions in perceived fatigue, weight, BMI, total cholesterol, and LDL, but the significant reductions in perceived fatigue were independent of changes in markers of metabolic health.

Spatiotemporal gait changes in people with multiple sclerosis with different disease progression subtypes

BACKGROUND

Gait impairment is common in people with multiple sclerosis (MS), but less is known about gait differences between MS disease progression subtypes. The objective here was to examine differences in spatiotemporal gait in MS and between relapsing-remitting and progressive subtypes during the timed-25-ft-walk test. Our specific aims were to investigate (1) spatiotemporal, (2) spatiotemporal variability, and (3) gait modulation differences between healthy controls and MS subtypes at preferred and fast walking speed.

METHODS

This study included 27 controls, 18 relapsing-remitting MS, and 13 progressive MS participants. Participants wore six inertial sensors and walked overground without walking aids at preferred and fast-as-possible speeds.

FINDINGS

Both MS groups had significantly lower walking speed than controls, with a trend towards lower preferred gait speed in progressive compared to relapsing-remitting MS (ES = 0.502). Although most spatiotemporal gait parameters differed between controls and MS groups, differences were not significant between MS subtypes in these parameters and their variability, with low to moderate effect sizes during preferred and fast walking. Both MS groups showed reduced modulation in gait compared to controls and no significant differences between MS subtypes.

INTERPRETATION

Gait in MS is altered compared to controls. Although gait may change with progressive MS, the overall small differences in the gait parameters between the MS subtypes observed in this sample suggests that those with the progressive form of MS who are independently ambulatory and without further clinically meaningful changes in gait speed may not show gait decrements greater than the relapsing-remitting form of the disease.

Alterations of Thalamic Nuclei Volumes and the Intrinsic Thalamic Structural Network in Patients with Multiple Sclerosis-Related Fatigue

Fatigue is a debilitating and prevalent symptom of multiple sclerosis (MS). The thalamus is atrophied at an earlier stage of MS and although the role of the thalamus in the pathophysiology of MS-related fatigue has been reported, there have been few studies on intra-thalamic changes. We investigated the alterations of thalamic nuclei volumes and the intrinsic thalamic network in people with MS presenting fatigue (F-MS). The network metrics comprised the clustering coefficient (Cp), characteristic path length (Lp), small-world index (σ), local efficiency (Eloc), global efficiency (Eglob), and nodal metrics. Volumetric analysis revealed that the right anteroventral, right central lateral, right lateral geniculate, right pulvinar anterior, left pulvinar medial, and left pulvinar inferior nuclei were atrophied only in the F-MS group. Furthermore, the F-MS group had significantly increased Lp compared to people with MS not presenting fatigue (NF-MS) (2.9674 vs. 2.4411, PAUC = 0.038). The F-MS group had significantly decreased nodal efficiency and betweenness centrality of the right mediodorsal medial magnocellular nucleus than the NF-MS group (false discovery rate corrected p < 0.05). The F-MS patients exhibited more atrophied thalamic nuclei, poorer network global functional integration, and disrupted right mediodorsal medial magnocellular nuclei interconnectivity with other nuclei. These findings might aid the elucidation of the underlying pathogenesis of MS-related fatigue.

The Effectiveness of Cognitive-Behavioral, Mindfulness and Acceptance and Commitment Therapies to Improving the Psychological Symptoms of Patients with Multiple Sclerosis in Iran (Systematic Review and Meta-analysis)

Context: Multiple sclerosis (MS) is a neurological disease in which the myelin lining the central nervous system is damaged and often occurs between the ages of 20 and 40. In addition to loss of motor, sensory, and cognitive function, patients with MS also experience related symptoms such as depression, anxiety, stress, fatigue, and pain. Objectives: The aim of this study was to systematically and meta-analyze the effectiveness of cognitive-behavioral, mindfulness and acceptance and commitment (CMAC) therapies to improving the psychological symptoms of patients with multiple sclerosis in Iran. Methods: The study was conducted using preferred reporting items for systematic reviews and meta-analysis. This study examined articles published from the beginning until November 20, 2021 in Persian and English on cognitive and behavioral interventions performed in Iran, in order to influence psychological symptoms for people with multiple sclerosis. Articles relevant to research were screened in external (Google Scholar, PubMed, Scopus, Science Direct, Web of Science) and internal databases (Sid, Magiran, Ganj, Irandoc, Civilica). The quality of the included RCTs was assessed using the Cochrane guideline risk of bias tool. The results were expressed in terms of mean difference (MD) and the corresponding 95% confidence interval. Data analyses were performed by RevMan5.4. Results: In the first stage of the search, 792 articles were obtained. After reviewing the titles of the articles, 701 articles were discarded due to irrelevance and duplication and 91 articles remained. Finally, 21 studies were selected by reviewing the abstracts and considering the inclusion criteria. Compared with the control group, the standardized mean difference (SMD) estimate depression was 1.60 (2.27, 0.93), for anxiety 0.49 (0.80, 0.19), for stress 0.97 (1.70, 0.23) and for fatigue 0.19 (2.75, 1.25) had a positive effect; But no significant effect on pain reduction equal to 0.49 (2.21, 1.23) was not found. Conclusions: The meta-analysis in the posttest showed that the effects of CMAC were considerable on reducing depression, anxiety, stress, and fatigue, but the effects were not notable for pain mitigation. Future high quality studies with follow-up evaluations are needed to support the effects of CMAC on reducing symptoms in people with multiple sclerosis and to evaluate the interventional features that enhance and maintain the effects.

How is neuromuscular fatigability affected by perceived fatigue and disability in people with multiple sclerosis?

Whereas fatigue is recognized to be the main complaint of patients with multiple sclerosis (PwMS), its etiology, and particularly the role of resistance to fatigability and its interplay with disability level, remains unclear. The purposes of this review were to (i) clarify the relationship between fatigue/disability and neuromuscular performance in PwMS and (ii) review the corticospinal and muscular mechanisms of voluntary muscle contraction that are altered by multiple sclerosis, and how they may be influenced by disability level or fatigue. Neuromuscular function at rest and during exercise are more susceptible to impairement, due to deficits in voluntary activation, when the disability is greater. Fatigue level is related to resistance to fatigability but not to neuromuscular function at rest. Neurophysiological parameters related to signal transmission such as central motor conduction time, motor evoked potentials amplitude and latency are affected by disability and fatigue levels but their relative role in the impaired production of torque remain unclear. Nonetheless, cortical reorganization represents the most likely explanation for the heightened fatigability during exercise for highly fatigued and/or disabled PwMS. Further research is needed to decipher how the fatigue and disability could influence fatigability for an ecological task, especially at the corticospinal level.

Fatigue, cognition and inflammatory biomarkers changes in response to computer-based cognitive training in multiple sclerosis patients: A randomized controlled trial

BACKGROUND: Fatigue, cognition problems and multiple sclerosis (MS) inflammatory processes became main quality of life indicators and points of clinical significance in MS practice. OBJECTIVE: The purpose of the current study was to investigate the changes in primary fatigue level, degree of cognitive dysfunction and level of inflammatory biomarkers in response to computer-based cognitive training in patients with MS. METHODS: A total of 40 remitting-relapse MS patients were divided into two groups, both groups were suffering cognitive decline, primary fatigue with elevated serum levels of the inflammatory biomarkers. Patients in the control group (GA) underwent conventional physical therapy program for MS including aerobic training, resistive training and a flexibility program in addition to placebo cognitive sessions, study group patients (GB) received an intensive computer-based cognitive program using the REHACOM software in addition to the same conventional physical therapy program as in GA. RESULTS: Significant decrease in the level of primary fatigue and in the serum levels of inflammatory biomarkers in GB patients compared to GA, as well as a remarkable improvement in the cognitive abilities in favor to the study group (GB) (p < 0.05). CONCLUSION: The addition of computer-based cognitive training in the rehabilitation program of MS patients is efficient in improving disease course via decreasing fatigue levels, enhancing cognitive abilities and reducing level of inflammatory biomarkers.

Validity and reliability characteristics of the Silhouettes Fatigue Scale in measuring multiple sclerosis-related fatigue in Turkish-speaking adults

BACKGROUND

The purpose of this study is to investigate the reliability and validity as well as the clinical utility of the Silhouettes Fatigue Scale (SFS), a single-item visual scale to assess fatigue, in adult patients with multiple sclerosis (MS).

METHODS

The study included 61 MS patients and 73 matched healthy controls. Demographic data and disease-related variables of all participants were recorded. Then, the SFS, Visual Analogue Scale (VAS)-fatigue, Fatigue Impact Scale (FIS), Fatigue Severity Scale (FSS), and Beck Depression Inventory (BDI) were applied. SFS, VAS-fatigue, and FSS were repeated after one week. Reliability was evaluated with the intra-class correlation coefficient (ICC) and Bland-Altman analysis. Validity was tested by comparison of healthy controls and patients with MS and correlations with other scales. Accuracy and clinical utility were also evaluated.

RESULTS

SFS scores were 4.49 ± 3.11 (mean ± SD) in MS patients and 1.40 ± 1.44 in healthy controls (p < .001). The ICC for SFS was 0.946. The mean difference between test-retest measurements of SFS was -0.04651 (-95% CI, -0.4815-0.38848), and there was no systemic bias. SFS scores were not correlated with the expanded disability status scale, whereas they were poorly correlated with BDI. Correlations ranging from poor to good were calculated between the SFS and other fatigue-related scales. The optimum cut-off score of the SFS scale was four, with a sensitivity of 0.72 and a specificity of 0.84.

CONCLUSION

This study demonstrated that the SFS is a reliable, responsive, and valid scale with acceptable sensitivity and specificity to assess and quantify clinically significant fatigue in MS patients. These findings as well as the brief and understandable nature of the SFS were encouraging that this scale has good clinical utility.

Prevalence of fatigue and its explicative variables among people with multiple sclerosis

BACKGROUND: Fatigue is the most prevalent symptom among people with multiple sclerosis (PwMS). Although exercise effectively reduces fatigue, the relationship between daily physical activity and fatigue has only recently been demonstrated. OBJECTIVE: The aim of this study was to evaluate the prevalence of fatigue and to understand the relationship with several variables in French PwMS. METHODS: Data were collected from 191 PwMS using Modified Fatigue Impact Scale (MFIS) and Fatigue Severity Scale (FSS) for fatigue, and the Godin Leisure-Time Exercise Questionnaire (GLTEQ) for physical activity. RESULTS: 110 PwMS (57%), 35 PwMS (18%) and 46 PwMS (24%) were considered as fatigued, non-fatigued and in the grey zone, respectively. Greater physical activity was observed in non-fatigued PwMS (20.2±19.8) compared to fatigued PwMS (12.5±14.1). FSS and MFIS scores were associated with physical activity (r = –0.28 and r = –0.25, respectively, p <  0.05). Using multivariate analysis, disability, physical activity and being unemployed explained 21% of the variance of the MFIS. CONCLUSIONS: The present study confirms that physical activity and fatigue are associated. Disability and unemployment status should also to be consider when assessing fatigue. Activity-oriented health policies should be redesigned to improve fatigue among PwMS.

Fatigue, physical activity and quality of life in people self-reporting symptoms of chronic venous disease

OBJECTIVE

The aim of this study was to quantify fatigue and quality of life (QoL) in people self-reporting chronic venous disease (CVD) symptoms or at risk of CVD within a large cohort representative of the French population. The relationship between self-reported physical activity and both fatigue and QoL was also investigated. We hypothesised that a greater fatigue and impaired QoL would exist in participants self-reporting CVD symptoms, with the impairments being attenuated in those with greater level of physical activity.

METHODS

Using a web-based, custom and adaptive survey, 3,008 participants were asked to self-report the presence of common symptoms and risk factors of CVD. Fatigue, QoL and physical activity were assessed using the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) scale, the Chronic Venous Insufficiency Quality of Life Questionnaire (CIVIQ-14) and the Godin-Shepard Leisure-Time Physical Activity Questionnaire (GSLTPAQ), respectively.

RESULTS

32% of the participants were categorized as having CVD symptoms whereas 50% were categorized as at risk of CVD. Fatigue was greater in participants with CVD symptoms than non-CVD participants (p < 0.001), with the score of participants at risk of CVD being intermediate (p ≤ 0.001). QoL was more impaired in participants with CVD symptoms compared to participants at risk of CVD (p < 0.001). In participants with CVD symptoms, there were relationships between fatigue and QoL (p < 0.001) and between physical activity and fatigue (p < 0.001). Despite the relationship between physical activity and QoL not reaching significance (p = 0.067), a lower QoL was found in insufficiently active as compared to active (p < 0.001) and moderately active (p < 0.001) participants with CVD symptoms.

CONCLUSIONS

Participants self-reporting CVD symptoms suffer from greater fatigue and impaired QoL. In this population, a higher level of physical activity is associated with reduced fatigue and a tendency toward improved QoL.

Fatigue in multiple sclerosis is associated with socioeconomic factors

OBJECTIVES

Fatigue is one of the leading causes of reduced quality of life and inability to work in people with multiple sclerosis (pwMS). Currently, no treatment effectively ameliorates fatigue. We still know little about what causes fatigue and which factors may contribute to fatigue. Knowledge about socioeconomic factors' role in fatigue might help us recognize strategies for the management of fatigue. Our aim was to explore whether socioeconomic factors are associated with the presence or level of perceived fatigue.

METHODS

This is a cross-sectional study of the MS population in three Norwegian counties. We used the Fatigue Scale for Motor and Cognitive Functions to assess self-reported fatigue, and obtained socioeconomic data from Statistics Norway and questionnaires. To assess self-reported anxiety and depression, we employed the Hospital Anxiety and Depression Scale. Clinical data were gathered from the hospital record system.

RESULTS

The response rate was 64% (1599/2512). Seventy percent of the respondents were female, and the mean age was 52 years. Higher levels of education were associated with lower levels of fatigue. Receiving a disability pension, being divorced and having children were all factors associated with higher levels of fatigue, as were low parental education, low income, current smoking, and autoimmune comorbidities. We found a higher prevalence of anxiety and depression in pwMS with fatigue compared to those without fatigue CONCLUSION: Female sex, high level of disability, anxiety, depression and socioeconomic factors were independently associated with fatigue in contemporary patients with MS. These factors should be considered when devising management strategies.

Symptom Interconnectivity in Multiple Sclerosis: A Narrative Review of Potential Underlying Biological Disease Processes

Introduction

Fatigue, cognitive impairment, depression, and pain are highly prevalent symptoms in multiple sclerosis (MS). These often co-occur and may be explained by a common etiology. By reviewing existing literature, we aimed to identify potential underlying biological processes implicated in the interconnectivity between these symptoms.

Methods

A literature search was conducted to identify articles reporting research into the biological mechanisms responsible for the manifestation of fatigue, cognitive impairment, depression, and pain in MS. PubMed was used to search for articles published from July 2011 to July 2021. We reviewed and assessed findings from the literature to identify biological processes common to the symptoms of interest.

Results

Of 693 articles identified from the search, 252 were selected following screening of titles and abstracts and assessing reference lists of review articles. Four biological processes linked with two or more of the symptoms of interest were frequently identified from the literature: (1) direct neuroanatomical changes to brain regions linked with symptoms of interest (e.g., thalamic injury associated with cognitive impairment, fatigue, and depression), (2) pro-inflammatory cytokines associated with so-called ‘sickness behavior,’ including manifestation of fatigue, transient cognitive impairment, depression, and pain, (3) dysregulation of monoaminergic pathways leading to depressive symptoms and fatigue, and (4) hyperactivity of the hypothalamic–pituitary-adrenal (HPA) axis as a result of pro-inflammatory cytokines promoting the release of brain noradrenaline, serotonin, and tryptophan, which is associated with symptoms of depression and cognitive impairment.

Conclusion

The co-occurrence of fatigue, cognitive impairment, depression, and pain in MS appears to be associated with a common set of etiological factors, namely neuroanatomical changes, pro-inflammatory cytokines, dysregulation of monoaminergic pathways, and a hyperactive HPA axis. This association of symptoms and biological processes has important implications for disease management strategies and, eventually, could help find a common therapeutic pathway that will impact both inflammation and neuroprotection.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40120-022-00368-2.

Multiple sclerosis-related fatigue lacks a unified definition: A narrative review

Fatigue is the most common symptom in multiple sclerosis (MS). Although MS-related fatigue (MS-F) strongly affects quality of life and social performance of patients, there is currently a lack of knowledge about its pathophysiology, which in turns leads to poor objective diagnosis and management. Recent studies have attempted to explain potential etiologies as well as treatments for MS-F. However, it seems that without a consensus on its nature, these data could not provide a route to a successful approach. In this Article, we review definitions, epidemiology, risk factors and correlated comorbidities, pathophysiology, assessment methods, neuroimaging findings, and pharmacological and nonpharmacological treatments of MS-F. Further studies are warranted to define fatigue in MS patients more accurately, which could result in precise diagnosis and management.

Prevalence of self-reported fatigue in intensive care unit survivors 6 months-5 years after discharge

Prolonged stays in intensive care units (ICU) are responsible for long-lasting consequences, fatigue being one of the more debilitating. Yet, fatigue prevalence for patients that have experienced ICU stays remains poorly investigated. This study aimed to evaluate fatigue prevalence and the level of physical activity in ICU survivors from 6 months to 5 years after ICU discharge using the Functional Assessment of Chronic Illness Therapy Fatigue (FACIT-F) and Godin questionnaires, respectively. Data from 351 ICU survivors (out of 1583 contacted) showed that 199 (57%) and 152 (43%) were considered as fatigued and non-fatigued, respectively. The median FACIT-F scores for fatigued versus non-fatigued ICU survivors were 21 (14–27) and 45 (41–48), respectively (p < 0.001). Time from discharge had no significant effect on fatigue prevalence (p = 0.30) and fatigued ICU survivors are less active (p < 0.001). In multivariate analysis, the only risk factor of being fatigued that was identified was being female. We reported a high prevalence of fatigue among ICU survivors. Sex was the only independent risk factor of being fatigued, with females being more prone to this symptom. Further studies should consider experimental approaches that help us understand the objective causes of fatigue, and to build targeted fatigue management interventions.

The Complex Interplay Between Trait Fatigue and Cognition in Multiple Sclerosis

Cognitive impairments are frequent in patients with Multiple Sclerosis (MS). Yet, the influence of MS-related symptoms on cognitive status is not clear. Studies investigating the impact of trait fatigue along with anxio-depressive symptoms on cognition are seldom, and even less considered fatigue as multidimensional. Moreover, these studies provided conflicting results.

Twenty-nine MS patients and 28 healthy controls, matched on age, gender and education underwent a full comprehensive neuropsychological assessment. Anxio-depressive and fatigue symptoms were assessed using the HAD scale and the MFIS, respectively. Six composite scores were derived from the neuropsychological assessment, reflecting the cognitive domains of working memory, verbal and visual learning, executive functions, attention and processing speed. Stepwise regression analyses were conducted in each group to investigate if trait cognitive and physical fatigue, depression and anxiety are relevant predictors of performance in each cognitive domain. In order to control for disease progression, patient’s EDSS score was also entered as predictor variable.

In the MS group, trait physical fatigue was the only significant predictor of working memory score. Cognitive fatigue was a predictor for executive functioning performance and for processing speed (as well as EDSS score for processing speed). In the healthy controls group, only an association between executive functioning and depression was observed.

Fatigue predicted cognition in MS patients only, beyond anxio-depressive symptoms and disease progression. Considering fatigue as a multidimensional symptom is paramount to better understand its association with cognition, as physical and cognitive fatigue are predictors of different cognitive processes.

Perceived Fatigue Impact and Cognitive Variability in Multiple Sclerosis

OBJECTIVE

People with Multiple Sclerosis (PwMS) and healthy controls (HCs) were evaluated on cognitive variability indices and we examined the relationship between fatigue and cognitive variability between these groups. Intraindividual variability (IIV) on a neuropsychological test battery was hypothesized to mediate the group differences expected in fatigue.

METHOD

Fifty-nine PwMS and 51 HCs completed a psychosocial interview and battery of neuropsychological tests and questionnaires during a 1-day visit. Fatigue in this study was measured with the Fatigue Impact Scale (FIS), a self-report multidimensional measure of fatigue. IIV was operationalized using two different measures, a maximum discrepancy score (MDS) and intraindividual standard deviation (ISD), in two cognitive domains, memory and attention/processing speed. Two mediation analyses with group (PwMS or HCs) as the independent variable, variability composite (memory or attention/processing speed) measures as the mediators, total residual fatigue (after accounting for age) as the outcome, and depression as a covariate were conducted. The Baron and Kenny approach to testing mediation and the PROCESS macro for testing the strength of the indirect effect were used.

RESULTS

Results of a mediation analysis using 5000 bootstrap samples indicated that IIV in domains of both attention/processing speed and memory significantly mediated the effect of patient status on total residual fatigue.

CONCLUSION

IIV is an objective performance measure that is related to differences in fatigue impact between PwMS and HCs. PwMS experience more variability across tests of attention/processing speed and memory and this experience of variable performance may increase the impact of fatigue.

OUP accepted manuscript

OBJECTIVE

We examined whether fatigue in multiple sclerosis (MS) is linked to switching processes when switching is measured by the Trail Making Test (TMT).

METHOD

Eighty-three participants with MS were administered a battery of standardized tests of switching, working memory, and processing speed. Ordinary least squares regression models were used to estimate the association between fatigue severity and switching above and beyond attention, working memory, and processing speed.

RESULTS

We found a negative association between TMT performance and fatigue severity score. When measures of processing speed and working memory were included in the model, the switching measure continued to uniquely contribute to fatigue severity.

CONCLUSIONS

There may be a unique relationship between fatigue and switching processes identifiable by clinical measures of switching. Future research should continue to investigate this relationship by using both behavioral and neural markers to test models of fatigue to eventually identify specific intervention targets.

Social Cognitive Theory variables as correlates of physical activity in fatigued persons with multiple sclerosis

BACKGROUND

There is interest in the application of behavioral interventions based on theory for increasing physical activity among adults with multiple sclerosis (MS). To date, researchers have applied theory such as Social Cognitive Theory (SCT) for identifying correlates of physical activity that can then inform the design and delivery of behavioral interventions. Such research often has been conducted in heterogeneous samples of persons with MS without a focus on those with a specific symptom, such as fatigue, that may be targeted by physical activity behavioral interventions. To that end, this study examined SCT variables (i.e., self-efficacy, barriers, outcome expectations, goal-setting, planning, social support, and functional limitations) as correlates of physical activity in persons with MS who self-reported elevated fatigue.

METHODS

Persons with MS (N=210; aged 49.6[13.2] years) who ambulated with or without assistance participated in the study. Participants completed self-report measures of fatigue, physical activity, and SCT variables and wore an ActiGraph GT3X+ accelerometer on a belt around the waist for 7 days. The accelerometer data were processed and delineated into time spent in light and moderate-to-vigorous physical activity (MVPA) based on MS-specific cut-points. We generated groups of fatigued (n=134) and non-fatigued (n=76) persons with MS based on the cut-off score of 4 for the Fatigue Severity Scale.

RESULTS

There were differences in physical activity and SCT variables between fatigued and non-fatigued persons with MS. Among those with fatigue, functional limitations (ρ=0.52), self-efficacy (ρ=0.31), and goal-setting (ρ=0.25) were associated with device-measured MVPA, and all SCT variables except outcome expectations were associated with self-reported physical activity. The regression analyses indicated self-efficacy, functional limitations, and goal-setting as significant correlates of MVPA in those with fatigue.

CONCLUSION

Self-efficacy, goal-setting, and social support may be important targets of SCT-based behavioral interventions for increasing physical activity among persons with MS who have fatigue.

Treatment of multiple sclerosis fatigue with the synthetic psychoactive drug modafinil

Multiple sclerosis (MS) is a complex disorder characterized by a broad spectrum of symptoms that evolve throughout the disease. Symptoms can be categorized as visible and invisible based on external sight recognition. However, although others poorly recognize it, invisible symptoms such as mood dysfunction, neuropathic pain, or fatigue can significantly affect activities of daily living and the quality of life of people with MS (PwMS). PwMS frequently complain of fatigue, which has physical or cognitive manifestations. Fatigue in MS does not improve or resolve with rest, and it is disproportionate with respect to the exerted effort. Fatigue management in MS is challenging, and a few pharmacological approaches have been successfully proposed. Among them, the drug modafinil has attracted attention because of its properties as a synthetic psychoactive drug. In this review, we focus on the evidence available to date, supporting the use of modafinil in MS fatigue. However, despite the availability of some trials evaluating the effects of modafinil on fatigue, their contrasting results failed to support its usefulness in fatigue management in MS.

Early Treatment Improvements in Depression Are Associated With Overall Improvements in Fatigue Impact and Pain Interference in Adults With Multiple Sclerosis

BACKGROUND

Depression, fatigue, and pain commonly co-occur in multiple sclerosis (MS) and are positively associated with one another. However, it is unclear whether treatment-related improvement in one of these symptoms is associated with improvements in the other two symptoms.

PURPOSE

This study examined whether early improvements in depressive symptoms, fatigue impact, and pain interference during a multisymptom intervention in persons with MS were associated with overall improvements in the other two symptoms.

METHODS

Secondary analysis of a randomized controlled trial in which both treatments improved depressive symptoms, fatigue, and pain interference. Adults with MS experiencing chronic pain, chronic fatigue, and/or moderate depressive symptoms (N = 154, 86% women) participated in an 8-week, telephone-delivered intervention: self-management (n = 69) or education (n = 85); intervention groups were combined for the current study. Outcome measures were depressive symptoms (PHQ-9), fatigue impact (Modified Fatigue Impact Scale), and pain interference (Brief Pain Inventory). Path analysis examined associations between pre-to-mid intervention improvement in one symptom (i.e., depression, fatigue, pain interference) and pre-to-post (overall) improvement in the other two symptoms.

RESULTS

Early reduction in depressive symptoms was associated with an overall reduction in pain interference and fatigue impact (p's < .01). Early reduction in fatigue impact was associated with an overall reduction in depressive symptom severity (p = .04) but not pain interference. Early reduction in pain interference was not associated with reductions in fatigue impact or depressive symptoms.

CONCLUSIONS

These findings suggest the potential importance of reducing depressive symptoms to overall improvement in fatigue and pain interference in persons with MS.

CLINICAL TRIAL REGISTRATIONS

NCT00944190.

Impact of the Swank and Wahls elimination dietary interventions on fatigue and quality of life in relapsing-remitting multiple sclerosis: The WAVES randomized parallel-arm clinical trial

Objective

To compare the effect of the modified Paleolithic elimination (Wahls) and low-saturated fat (Swank) diets in relapsing-remitting MS (RRMS).

Methods

Individuals (n = 87) with RRMS were randomized to the Swank or Wahls diets in a parallel group clinical trial consisting of four timepoints: 1) run-in, 2) baseline, 3) 12-weeks, and 4) 24-weeks.

Results

77 participants completed 12 weeks and 72 completed 24 weeks. The 12-week change from baseline in fatigue was -0.94 ± 0.18 (FSS) and -9.87 ± 1.93 (MFIS; both p < 0.0001) for Swank, and -0.71 ± 0.24 (FSS; p = 0.004) and -14.41 ± 2.22 (MFIS; p ≤ 0.0001) for Wahls. Physical MSQoL scores improved by 6.04 ± 2.18 (p = 0.006) for Swank and by 14.5 ± 2.63 (p < 0.0001) for Wahls. Mental MSQoL scores improved by 11.3 ± at 2.79 (p < 0.0001) for Wahls while the Swank did not change (3.85 ± 2.63; p = 0.14). Neither group showed significant changes in 6-minute walking distance at 12 weeks. All outcomes were maintained or further improved at 24 weeks.

Conclusions

Both diets were associated with clinically meaningful within-group reductions in fatigue and improvements in QoL.Trial Registration: Clinicaltrials.gov Identifier: NCT02914964.

Cognitive fatigability in multiple sclerosis: How does performance decline over time on the Paced Auditory Serial Addition Test?

BACKGROUND

Cognitive fatigability (CF) can be defined as an inability to maintain an optimal level of performance throughout a sustained cognitive task. It remains unclear, however, whether there is a specific moment during a cognitive task, such as the Paced Auditory Serial Addition Test (PASAT), when performance begins to break down. Thus, the present study aimed to evaluate how performance declines over time on the PASAT in people with multiple sclerosis (PwMS) compared to healthy controls.

METHODS

178 PwMS and 186 control participants were administered the 3" and 2" PASAT as part of a larger battery of neuropsychological tests. To examine how CF differed between the groups, repeated measures ANOVAs were used to evaluate the cumulative error rates made by each group throughout the task. In addition, how the error rate developed across the task on each trial was examined to evaluate in more detail the difference between groups with respect to how performance declined from the beginning to the end of the task. Lastly, exploratory two-way independent sample ANOVAs examined whether there was an influence of stimulus complexity (single vs. double-digit answers) on task performance.

RESULTS

Compared to healthy controls, PwMS produced a greater number of errors overall on the PASAT and demonstrated more vulnerability to CF than healthy controls, as reflected by a greater number of errors made towards the end of the task. This difference was more noticeable on the 3" PASAT, given the difficulty both groups experienced on the 2" form. On the 3" PASAT, by Trial 37, PwMS had made significantly more cumulative errors than controls, however the rate of error generation was largely consistent and linear from the beginning to the end. Some of the group differences observed may be partially attributable to stimulus complexity influencing task performance.

CONCLUSIONS

The 3" PASAT is more sensitive to group differences in CF and error generation than the 2" PASAT. With respect to CF, the greater vulnerability observed in the MS group is not due to a breakdown in performance or an increase in the rate of error generation at any specific point during the task; rather there is a linear decline in performance from the start. These results suggest that PwMS struggle to maintain optimal performance during sustained cognitive effort from the very beginning and demonstrate a steeper, but steady, rate of decline over time.

Ethical considerations in the treatment of multiple sclerosis fatigue

Fatigue is the most common symptom and a leading cause of disability multiple sclerosis (MS). Despite the lack of evidence, several medications are frequently prescribed by physicians to ameliorate fatigue in patients with MS. However, a recent study demonstrated that improvement in fatigue severity with these medications appears to be due to placebo effect and is also is associated with more frequent adverse events than the placebo. These findings raise ethical concerns surrounding the initiation and discontinuation of these treatments for fatigue in MS. Starting these medications for the treatment of MS fatigue for their placebo effect may not be justified. However, stopping the medications in patients who report symptomatic benefits and have no side effects may also not be ethical. In MS care non-pharmacological approaches for fatigue treatment, such as exercise and cognitive behavioral therapy, should now be prioritized. Novel study designs may be necessary to address placebo response in future clinical trials evaluating interventions for fatigue in MS.

Comprehensive Approach to Management of Multiple Sclerosis: Addressing Invisible Symptoms-A Narrative Review

Multiple sclerosis (MS) is a chronic autoimmune inflammatory disease of the central nervous system, leading to neurodegeneration and manifesting as a variety of symptoms. These can include "invisible" symptoms, not externally evident to others, such as fatigue, mood disorders, cognitive impairments, pain, bladder/bowel dysfunction, sexual dysfunction, and vision changes. Invisible symptoms are highly prevalent in people living with MS, with multifactorial etiology and potential to impact the disease course. Patient experiences of these symptoms include both physical and psychosocial elements, which when unaddressed negatively influence many aspects of quality of life and perception of health. Despite the high impact on patient lives, gaps persist in awareness and management of these hidden symptoms. The healthcare provider and patient author experiences brought together here serve to raise the profile of invisible symptoms and review strategies for a team-based approach to comprehensive MS care. We summarize the current literature regarding the prevalence and etiology of invisible symptoms to convey the high likelihood that a person living with MS will contend with one or more of these concerns. We then explore how open communication between people living with MS and their care team, stigma mitigation, and shared decision-making are key to comprehensive management of invisible symptoms. We recommend validated screening tools and technological advancements that may be incorporated into MS care to regularly monitor these symptoms, offering insight into how healthcare providers can both educate and listen to patients, with the goal of improved patient quality of life. By pairing clinical knowledge with an understanding and consideration of the patient perspective, providers will be equipped to foster a patient-centered dialogue that encourages shared decision-making. Invisible symptoms of MS.

High prevalence of fatigue in contemporary patients with multiple sclerosis

Objective

The prevalence of multiple sclerosis (MS)-related fatigue may have changed due to new diagnostic criteria and new disease modifying drugs. We aimed to assess the prevalence of fatigue in a contemporary MS cohort, and to explore associations between fatigue and clinical and demographic factors.

Methods

This is a cross-sectional study of the MS population in three Norwegian counties. Fatigue was assessed with the Fatigue Scale for Motor and Cognitive Functions (FSMC). We also assessed self-reported anxiety, depression and daytime sleepiness.

Results

The response rate was 64% (1599/2512). The mean age of the participants was 52 ± 13 years, median EDSS was 2.5 (IQR 1.5-3.0) and median disease duration from onset was 16 years (IQR 8-25). We found a prevalence of fatigue of 81%. Women had a higher prevalence of fatigue than men (83% vs 78%, p = 0.02). The prevalence increased with age (p < 0.001) and with increasing disease severity (p < 0.001), but in multivariate analyses, only sex and disease severity remained independent determinants of fatigue. Anxiety, depression, and daytime sleepiness were more prevalent in patients with fatigue than in those without fatigue (all p-values < 0.001).

Conclusion

The prevalence of fatigue is high in contemporary patients with MS. Fatigue is associated with female sex and level of disability, as well as with anxiety, depression and excessive daytime sleepiness.

Cognitive fatigue in multiple sclerosis is associated with alterations in the functional connectivity of monoamine circuits

Fatigue is a highly prevalent and debilitating symptom in multiple sclerosis, but currently the available treatment options have limited efficacy. The development of innovative and efficacious targeted treatments for fatigue in multiple sclerosis has been marred by the limited knowledge of the underlying mechanisms. One of the hypotheses postulates that multiple sclerosis pathology might cause reduced monoaminergic release in the central nervous system with consequences on motivation, mood and attention. Here, we applied the recently developed Receptor-Enriched Analysis of Functional Connectivity by Targets method to investigate whether patients with high and low fatigue differ in the functional connectivity (FC) of the monoamine circuits in the brain. We recruited 55 patients with multiple sclerosis, which were then classified as highly fatigued or mildly fatigued based on their scores on the cognitive sub-scale of the Modified Fatigue Impact scale. We acquired resting-state functional MRI scans and derived individual maps of connectivity associated with the distribution of the dopamine, noradrenaline and serotonin transporters as measured by positron emission tomography. We found that patients with high fatigue present decreased noradrenaline transporter (NAT)-enriched connectivity in several frontal and prefrontal areas when compared to those with lower fatigue. The NAT-enriched FC predicted negatively individual cognitive fatigue scores. Our findings support the idea that alterations in the catecholaminergic functional circuits underlie fatigue in multiple sclerosis and identify the NAT as a putative therapeutic target directed to pathophysiology.

Altered in vivo brain GABA and glutamate levels are associated with multiple sclerosis central fatigue

PURPOSE

Fatigue is a common symptom in patients with multiple sclerosis (MS) with unknown pathophysiology. Dysfunction of the GABAergic/glutamatergic pathways involving inhibitory and excitatory neurotransmitters such as  γ-aminobutyric acid (GABA) and glutamine + glutamate pool (Glx) have been implicated in several neurological disorders. This study is aimed to evaluate the potential role of GABA and Glx in the origin of central fatigue in relapse remitting MS (RRMS) patients.

METHODS

24 RRMS patients and 16 age- and sex-matched healthy controls (HC) were scanned using Mescher-Garwood point resolved spectroscopy (MEGA-PRESS) with a 3 T system to quantify GABA+ and Glx from prefrontal (PFC) and sensorimotor (SMC) cortices. Self-reported fatigue status was measured on all participants using the Modified Fatigue Impact Scale (MFIS).

RESULTS

RRMS patients had higher fatigue scores relative to HC (p ≤  0.05). Compared to HC, Glx levels in RRMS patients were significantly decreased in SMC (p =  0.04). Significant correlations were found between fatigue scores and GABA+ (r = -0.531, p =  0.008) and Glx (r = 0.511, p =  0.018) in PFC. Physical fatigue was negatively correlated with GABA+ in SMC and PFC (r = -0.428 and -0.472 respectively, p ≤  0.04) and positively with PFC Glx (r = 0.480, p =  0.028).

CONCLUSION

The associations between fatigue and GABA + and Glx suggest that there might be dysregulation of GABAergic/glutamatergic neurotransmission in the pathophysiological mechanism of central fatigue in MS.

Memantine for Multiple Sclerosis: A Systematic Review and Meta-Analysis of Randomized Trials

Background: Multiple sclerosis (MS), a disabling demyelinating disease of the central nervous system, is associated with cognitive impairment, spasticity, and fatigue. There are still no established guidelines on the management of MS-related sequela. Memantine has the potential to reduce glutamate toxicity, thereby reducing consequent cognitive impairment, spasticity, and fatigue.

Objectives: This study aims to determine the efficacy and safety of memantine in preventing cognitive impairment, reducing spasticity and fatigue, and controlling disability in MS patients through a review of relevant randomized trials.

Methods: MEDLINE, CENTRAL, Scopus, Embase, LILACS, ClinicalTrials.gov, and HERDIN were searched from inception to May 2020 for relevant trials.

Results: The search yielded 203 articles; four studies were included in the analysis. Pooled evidence shows that memantine compared with placebo does not significantly improve PASAT, ASS, MFIS, and EDSS scores of patients with MS. Memantine is associated with mild adverse drug events such as dizziness, fatigue, and anxiety.

Conclusion: There is not enough evidence to support the efficacy of memantine in preventing cognitive decline, controlling spasticity, reducing fatigue, and preventing disability. Future researches should consider the different MS subtypes, effect of co-administration of disease-modifying therapies, longer duration of administration, and more sensitive outcome measures to evaluate the potential benefit of memantine in MS.

Design considerations for a multiple sclerosis fatigue mobile app MS Energize: A pragmatic iterative approach using usability testing and resonance checks

Multiple sclerosis (MS) is a chronic neurological condition affecting around 2.2 million people worldwide. The illness includes a range of symptoms, with fatigue considered to be one of the most disabling. This paper describes how a pragmatic and iterative approach, supported by usability and resonance testing, was used to build a minimum viable product of MS Energize-or MS Energise in UK English regions. MS Energise is a mobile application focused on self-management of fatigue for people with MS. The iterative approach included various stages of testing, during which user feedback including comments about interface, navigation and content, was sought to inform incremental app development and continual improvement. Usability testing was conducted with 11 people with longstanding multiple sclerosis in New Zealand and the United Kingdom, and focused on particular sections of the app as well as the accessibility of the app to users with MS. Two participants contributed to further resonance testing post-release to ensure the app was perceived as relevant and useful to the user. The usability testing and resonance testing phases suggested that user experience of MS Energise was mostly positive. Participants provided a number of suggestions for improvements to aspects of content and design; some of which we implemented during our app development process. Findings will also contribute to future planning and design iteration to enhance the user experience. The next step is further improvement of MS Energise prior to a trial of its clinical and cost effectiveness.

Associations between fatigue impact and lifestyle factors in people with multiple sclerosis - The Danish MS hospitals rehabilitation study

BACKGROUND

The lack of medical treatment options to reduce fatigue in patients with multiple sclerosis (MS) emphasize the importance of identifying potential non-pharmacological modifiable factors, as this may help advance current treatment strategies. The aim of this study was to identify potential modifiable lifestyle factors as well as patient- and disease-related characteristics, that are associated with fatigue in a large sample of clinically well-characterized patients with MS.

METHODS

This study was a secondary analysis of a pragmatic randomized controlled trial of inpatient multidisciplinary rehabilitation in Denmark. MS patients aged 18 to 65 years and with a disease severity score ≤ 7.5 according to the Expanded Disability Status Scale participated. Data on patient- and disease-related characteristics, fatigue impact (Modified Fatigue Impact Scale (MFIS)), and on lifestyle factors (tobacco smoking, alcohol intake, and physical activity), were collected at baseline. A linear mixed model was used to compare MFIS total, physical, cognitive, and psychosocial scores across subgroups of selected characteristics. Regression analyses were used to examine associations between lifestyle factors and MFIS total, physical, cognitive, and psychosocial scores.

RESULTS

In the sample of 417 MS patients, median age was 51 years, 69% were female, median time since diagnosis was 8 years, with 41% having relapsing remitting MS. Higher MFIS total scores were observed in MS patients with shorter time since diagnosis, being a tobacco smoker, and not undertaking regular physical activity. Somewhat similar findings were observed for MFIS subscores (physical, cognitive, psychosocial), especially MFIS physical scores. In the multivariate analyses, physical activity was significantly associated with fatigue impact on total, physical and psychosocial functioning. Tobacco smoking was significantly associated with fatigue impact on psychosocial functioning. Alcohol intake was not associated with fatigue impact. None of the lifestyle factors were associated with fatigue impact on cognitive functioning. In the adjusted models time since diagnosis was significantly associated with fatigue impact on total, physical and cognitive functioning, as was disease severity with fatigue impact on physical and cognitive functioning.

CONCLUSION

Physical activity showed the most pronounced associations with fatigue impact on physical and psychosocial functioning, while the impact on cognitive functioning showed a trend. Tobacco smoking contributed significantly to impact on psychosocial functioning, while alcohol intake did not contribute to fatigue impact. Introducing or supporting maintenance of physical activity/exercise and cessation of tobacco smoking seems to be a useful approach for rehabilitation services to help patients with MS manage fatigue.

Relationship between intensive care unit-acquired weakness, fatigability and fatigue: What role for the central nervous system?

PURPOSE

To provide a comprehensive review of studies that have investigated fatigue in intensive care unit (ICU) survivors and questions the potential link between intensive care unit-acquired weakness (ICUAW), fatigability and fatigue. We also question whether the central nervous system (CNS) may be the link between these entities.

MATERIAL AND METHODS

A narrative review of the literature that investigated fatigue in ICU survivors and review of clinical trials enabling understanding of CNS alterations in response to ICU stays.

RESULTS

Fatigue is a pervasive and debilitating symptom in ICU survivors that can interfere with rehabilitation. Due to the complex pathophysiology of fatigue, more work is required to understand the roles of ICUAW and/or fatigability in fatigue to provide a more holistic understanding of this symptom. While muscle alterations have been well documented in ICU survivors, we believe that CNS alterations developing early during the ICU stay may play a role in fatigue.

CONCLUSIONS

Fatigue should be considered and treated in ICU survivors. The causes of fatigue are likely to be specific to the individual. Understanding the role that ICUAW and fatigability may have in fatigue would allow to tailor individual treatment to prevent this persistent symptom and improve quality of life.

Conceptualising illness and disease: reflections on Sharpe and Greco (2019)

In a recent paper, Sharpe and Greco suggest that chronic fatigue syndrome/myalgic encephalomyelitis (MECFS) can be viewed as an instance of "illness without disease", and consequently, treatment should be directed towards altering the patient's experience of, and response to, their symptoms. We discuss two broad issues that arise from Sharpe and Greco's article, one relating to the assumptions they make about MECFS and its treatment specifically, and the other relating to their conceptualisation of the illness/disease dichotomy. We argue that the term "illness without disease", in the sense that Sharpe and Greco use it, is problematic because it can lead to unwarranted causal assumptions. Following these critical comments, we present a new framework for conceptualising the relationship between explanatory disease models and the experience of illness.

Safety and efficacy of amantadine, modafinil, and methylphenidate for fatigue in multiple sclerosis: a randomised, placebo-controlled, crossover, double-blind trial

BACKGROUND

Methylphenidate, modafinil, and amantadine are commonly prescribed medications for alleviating fatigue in multiple sclerosis; however, the evidence supporting their efficacy is sparse and conflicting. Our goal was to compare the efficacy of these three medications with each other and placebo in patients with multiple sclerosis fatigue.

METHODS

In this randomised, placebo-controlled, four-sequence, four-period, crossover, double-blind trial, patients with multiple sclerosis who reported fatigue and had a Modified Fatigue Impact Scale (MFIS) score of more than 33 were recruited at two academic multiple sclerosis centres in the USA. Participants received oral amantadine (up to 100 mg twice daily), modafinil (up to 100 mg twice daily), methylphenidate (up to 10 mg twice daily), or placebo, each given for up to 6 weeks. All patients were intended to receive all four study medications, in turn, in one of four different sequences with 2-week washout periods between medications. A biostatistician prepared a concealed allocation schedule, stratified by site, randomly assigning a sequence of medications in approximately a 1:1:1:1 ratio, in blocks of eight, to a consecutive series of numbers. The statistician and pharmacists had no role in assessing the participants or collecting data, and the participants, caregivers, and assessors were masked to allocation. The primary outcome measure was the MFIS measured while taking the highest tolerated dose at week 5 of each medication period, analysed by use of a linear mixed-effect regression model. This trial is registered with ClinicalTrials.gov, NCT03185065 and is closed.

FINDINGS

Between Oct 4, 2017, and Feb 27, 2019, of 169 patients screened, 141 patients were enrolled and randomly assigned to one of four medication administration sequences: 35 (25%) patients to the amantadine, placebo, modafinil, and methylphenidate sequence; 34 (24%) patients to the placebo, methylphenidate, amantadine, and modafinil sequence; 35 (25%) patients to the modafinil, amantadine, methylphenidate, and placebo sequence; and 37 (26%) patients to the methylphenidate, modafinil, placebo, and amantadine sequence. Data from 136 participants were available for the intention-to-treat analysis of the primary outcome. The estimated mean values of MFIS total scores at baseline and the maximal tolerated dose were as follows: 51·3 (95% CI 49·0-53·6) at baseline, 40·6 (38·2-43·1) with placebo, 41·3 (38·8-43·7) with amantadine, 39·0 (36·6-41·4) with modafinil, and 38·6 (36·2-41·0) with methylphenidate (p=0·20 for the overall medication effect in the linear mixed-effect regression model). As compared with placebo (38 [31%] of 124 patients), higher proportions of participants reported adverse events while taking amantadine (49 [39%] of 127 patients), modafinil (50 [40%] of 125 patients), and methylphenidate (51 [40%] of 129 patients). Three serious adverse events occurred during the study (pulmonary embolism and myocarditis while taking amantadine, and a multiple sclerosis exacerbation requiring hospital admission while taking modafinil).

INTERPRETATION

Amantadine, modafinil, and methylphenidate were not superior to placebo in improving multiple sclerosis fatigue and caused more frequent adverse events. The results of this study do not support an indiscriminate use of amantadine, modafinil, or methylphenidate for the treatment of fatigue in multiple sclerosis.

FUNDING

Patient-Centered Outcomes Research Institute.