Validation of the Modified Fatigue Impact Scale in patients with systemic lupus erythematosus.

INTRODUCTION: Patients with systemic lupus erythematosus (SLE) experience significant fatigue, a debilitating symptom associated with reduced quality of life. There has not yet been agreed on a simple and reliable method for assessing fatigue in SLE. OBJECTIVES: To investigate the internal consistency, test-retest reliability and construct validity (convergent and discriminant validity) of the Modified Fatigue Impact Scale (MFIS) in patients with SLE. The secondary objective was to investigate the contribution of disease activity and organ damage to fatigue. METHODS: Fatigue was assessed using the MFIS in 61 patients with SLE. Internal consistency of MFIS was assessed with Cronbach's alpha (α) and Principal Component Analysis. Test-retest reliability was evaluated using the intraclass correlation coefficient (ICC). Construct validity was studied using Spearman's rank correlation (rs). Associations between MFIS and disease activity and organ damage were estimated with rs. RESULTS: Internal consistency of the MFIS was excellent with Cronbach's α = 0.97 (95% confidence interval (CI): 0.96-0.98) for the complete scale. Test-retest reliability was good with ICC = 0.89 (95% CI: 0.78-0.95, p < 0.001). Construct validity was confirmed by Spearman's correlation (VT-SF36: rs = -0.73, p < 0.001. MH-SF36: rs = 0.70, p < 0.001). No significant correlation was found between the MFIS and SLEDAI (rs = 0.03, p = 0.83). There was a moderate correlation between MFIS and SLICC Damage Index (rs = 0.43, p < 0.001). CONCLUSION: The present study found the MFIS to be a reliable and valid instrument for assessing fatigue in SLE. Further investigations are needed to clarify if an association between measured fatigue and disease components exists.

Translation and initial validation of Chinese (Cantonese) version of Modified Fatigue Impact Scale (MFIS-C) in people with stroke.

PURPOSE: To translate and culturally adapt the Modified Fatigue Impact Scale (MFIS) to Chinese version, and to psychometrically test it in stroke population. METHODS: This study consisted of 2 phases. In phase one, we translated and culturally adopted the original English version of MFIS into Chinese (Cantonese) (MFIS-C). In phase two, the MFIS was psychometrically tested using a cohort of community-dwelling people with stroke (n = 101) and healthy control (n = 50). Among the stroke participants, 52 of them were reassessed after a 1-week interval. RESULTS: The MFIS-C demonstrated satisfactory content validity and good to excellent internal consistency. The overall MFIS-C and its subscales have good test-retest reliability. The MDC95 were 14.86, 7.49, and 9.70 for the overall MFIS-C physical, cognitive and psychosocial subscales, respectively. The overall MFIS-C and its 2 subscales have significant weak to moderate negative correlations with the Community Integration Measure and the 12-item Short Form Health Survey Version 2. Our findings revealed that the people with chronic stroke living in Hong Kong were reported to have high level of fatigue. CONCLUSION: The MFIS-C is a reliable and valid measure for assessing the level of fatigue in people with stroke.

Effects on Motor Control of Personalized Neuromodulation Against Multiple Sclerosis Fatigue.

Fatigue is a hidden symptom of Multiple Sclerosis (MS) disease that nevertheless impacts severely on patients' everyday life. Evidence indicates the involvement of the sensorimotor network and its inter-nodes communication at the basis of this symptom. Two randomized controlled trials (RCTs) showed that the personalized neuromodulation called Fatigue Relief in Multiple Sclerosis (FaReMuS) efficaciously fights multiple sclerosis (MS) fatigue. By this Proof of Concept study, we tested whether FaReMuS reverts the alteration of the brain-muscular synchronization previously observed occurring with fatigue. The cortico muscular coherence (CMC) was studied in 11 patients before and after FaReMuS, a 5-day tDCS (1.5 mA, 15 min per day) anodal over the whole body's somatosensory representation (S1) via a personalized MRI-based electrode (35 cm2) against the occipital cathode (70 cm2). Before FaReMuS, the CMC was observed at a mean frequency of 31.5 ± 1.6 Hz (gamma-band) and positively correlated with the level of fatigue (p = .027). After FaReMuS, fatigue reduced in average of 28% ± 33% the baseline level, and the CMC frequency reduced to 26.6 ± 1.5 Hz (p = .022), thus forthcoming the physiological beta-band as observed in healthy people. The personalized S1 neuromodulation treatment, ameliorating the central-peripheral communication that subtends simple everyday movements, supports the appropriateness of neuromodulations aiming at increasing the parietal excitability in fighting MS fatigue. The relationship between central-peripheral features and fatigue profile strengthens a central more than peripheral origin of the symptom.

Fatigue and fluid hydration status in multiple sclerosis: A hypothesis.

BACKGROUND: Fatigue is a prevalent and functionally disabling symptom for individuals living with multiple sclerosis (MS) which is poorly understood and multifactorial in etiology. Bladder dysfunction is another common MS symptom which limits social engagement and quality of life. To manage bladder issues, individuals with MS tend to limit their fluid intake, which may contribute to a low-hydration (LoH) state and fatigue. OBJECTIVE: To evaluate the relationship between patient-reported MS fatigue, bladder dysfunction, and hydration status. METHODS: We performed a prospective cross-sectional study in 50 women with MS. Participants submitted a random urine sample and completed several fatigue-related surveys. Using a urine specific gravity (USG) threshold of 1.015, we classified MS subjects into two groups: high-hydration (HiH) and LoH states. RESULTS: LoH status was more common in MS subjects with bladder dysfunction. Statistically significant differences in self-reported Fatigue Performance Scale were observed between HiH and LoH subjects (p = 0.022). USG was significantly correlated with fatigue as measured by the MS Fatigue Severity Scale (FSS) score (r = 0.328, p = 0.020). CONCLUSION: Hydration status correlates with self-reported fatigue, with lower fatigue scores found in those with HiH status (USG < 1.015).

The telephone-based application of the modified fatigue impact scale in individuals with multiple sclerosis: An investigation of measurement properties.

BACKGROUND: Fatigue is one of the most common symptoms reported by individuals with multiple sclerosis and it contributes to the reduction of the functionality. Therefore, it is important to assess the impact of fatigue on daily living of individuals with multiple sclerosis. The Modified Fatigue Impact Scale (MFIS) is an instrument to assess the perception of the impact of fatigue. However, there have been no investigations about the measurement properties of this instrument administered over the telephone for individuals with multiple sclerosis. OBJECTIVES: To verify the concurrent validity, the test-retest reliability, the standard error of measurement (SEM) and the minimal detectable change (MDC) of the MFIS applied over the telephone to assess the perception of the impact of fatigue of individuals with multiple sclerosis. METHODS: The MFIS, composed of 21 items covering three domains: physical, cognitive and psychosocial, was applied at three different moments with an interval of 5-7 days. To establish the concurrent criterion validity, the face-to-face application and the first evaluation by telephone were used. The two telephone assessments were used to assess the test-retest reliability The intraclass correlation coefficient (ICC) with 95 % confidence interval (CI) and the Bland-Altman method were used. The standard error of measurement (SEM) and the MDC was calculated according to reliability results. RESULTS: Thirty individuals (40.83 ± 10.61, 60 % female) were included. The median score on the Expanded Disability Status Scale was 2.00 (±4.00). The majority of participants experienced fatigue (n = 17; 56.67 %). A significant and high magnitude correlation (0.70 ≤ ICC ≤ 0.87, p < 0.001) was found in the investigation of concurrent criterion validity. The Bland-Altman method showed a mean difference between 0.70 to 2.17 points between face-to-face and telephone-based application of the MFIS. For test-retest reliability, a significant and very high magnitude correlation (0.91 ≤ ICC ≤ 0.97, p < 0.001) was found. The Bland-Altman method showed a mean difference between -0.03 and -0.77 points between two telephone-based applications. The SEM and the MDC were 0.71 and 1.97 points. CONCLUSION: The telephone-based application of the MFIS to assess the perceived impact of fatigue in individuals with multiple sclerosis demonstrated adequate measurement properties, and may be a valuable tool to assess patients in clinical practice.

The effect of Nintendo® Wii® on balance in people with multiple sclerosis: a pilot randomized control study.

Improvement of sensory strategies is a relevant part of balance rehabilitation in multiple sclerosis (MS). This study aimed to Assess the effectiveness of visual-feedback exercises in improving balance in MS. We divided 36 patients into Wii and control-treated groups that underwent balance rehabilitation. Outcomes were obtained for Berg Balance Scale (BBS), Modified Fatigue Impact Scale, and sway area under conditions of opened and closed eyes. BBS showed a statistically significant improvement (from 49.6 to 54.6 points, p < 0.05) in the Wii group. Interactive visual-feedback exercises such as Wii could be more effective than the current standard protocol in improving balance disorders in MS.

A combined inspiratory and expiratory muscle training program improves respiratory muscle strength and fatigue in multiple sclerosis.

OBJECTIVE: To determine the effects of a short-duration, combined (inspiratory and expiratory), progressive resistance respiratory muscle training (RMT) protocol on respiratory muscle strength, fatigue, health-related quality of life, and functional performance in individuals with mild-to-moderate multiple sclerosis (MS). DESIGN: Quasi-experimental before-after trial. SETTING: University rehabilitation research laboratory. PARTICIPANTS: Volunteers with MS (N=21) were divided into 2 groups: RMT (n=11; 9 women, 2 men; mean age ± SD, 50.9 ± 5.7y, mean Expanded Disability Status Scale score ± SD, 3.2 ± 1.9) and a control group that did not train (n=10; 7 women, 3 men; mean age ± SD, 56.2 ± 8.8y, mean Expanded Disability Status Scale score ± SD, 4.4 ± 2.1). Expanded Disability Status Scale scores ranged from 1 to ≤6.5. No patients withdrew from the study. INTERVENTION: Training was a 5-week combined progressive resistance RMT program, 3d/wk, 30 minutes per session. MAIN OUTCOME MEASURES: The primary outcome measures were maximal inspiratory pressure and expiratory pressure and the Modified Fatigue Impact Scale. All subjects completed secondary measures of pulmonary function, the six-minute walk test, the timed stair climb, the Multiple Sclerosis Self-Efficacy Scale, the Medical Outcomes Study 36-Item Short-Form Health Survey, and the Physical Activity Disability Scale. RESULTS: Maximal inspiratory pressure and expiratory pressure (mean ± SD) increased 35% ± 22% (P<.001) and 26% ± 17% (P<.001), respectively, whereas no changes were noted in the control group (12% ± 23% and -4% ± 17%, respectively). RMT improved fatigue (Modified Fatigue Impact Scale, P<.029), with no change or worsening in the control group. No changes were noted in the six-minute walk test, stair climb, Multiple Sclerosis Self-Efficacy Scale, or Physical Activity Disability Scale in the RMT group. The control group had decreases in emotional well-being and general health (Medical Outcomes Study 36-Item Short-Form Health Survey). CONCLUSIONS: A short-duration, combined RMT program improved inspiratory and expiratory muscle strength and reduced fatigue in patients with mild to moderate MS.

Sociodemographic and Clinical Determinants of Fatigue in Multiple Sclerosis.

Fatigue is the most common and disabling symptom in patients with multiple sclerosis (PwMS), representing one of the main determinants of reduced quality of life among PwMS due to its interference with social activities and work capacity. This study aimed to identify the sociodemographic determinants of fatigue in a cohort of 150 PwMS and 100 healthy controls (HCs). Fatigue was assessed using one of the most suitable and appropriate tools for measuring the degree of fatigue: the Modified Fatigue Impact Scale (MFIS). By comparing the median scores for the MFIS, we observed that the PwMS group had significantly higher MFIS scores than the HCs (p = 0.0001). In PwMS, MFIS scores correlated positively with age, total number of relapses, total disease duration, disability status, and Beck Depression Inventory-II score and negatively with cognitive performance. Patients with relapsing-remitting MS had significantly lower fatigue levels than those with secondary progressive MS (p = 0.0010). Fatigue levels were significantly lower among male than female PwMS (p = 0.0120). Other determinant factors of fatigue in our study proved to be the marital and occupational status, as well as the presence of children, but in a linear multivariate regressions analysis with MFIS score as the dependent variable, the fatigue levels were influenced only by sex, occupational status, marital status, children status, and BDI-II test results. Considering the significant impact of fatigue on the quality of life of PwMS, clinicians must diagnose fatigue as early as possible, identify its modifiable determinants, and manage it effectively to increase their quality of life.

Psychiatric Symptoms and Fatigue in COVID-19 Survivors.

INTRODUCTION: Psychiatric symptoms and fatigue are common after the coronavirus disease 2019 (COVID-19) illness. The cause of these symptoms is direct neuronal injury and indirect injury with immune-mediated inflammation. In addition, social factors also affect mental health. OBJECTIVE: We aim to compare psychiatric symptoms and fatigue between COVID-19 survivors and healthy controls. MATERIAL AND METHODS: We prospectively evaluated 100 COVID-19 survivors for anxiety, depression, positive affect, and behavior control using the Mental Health Inventory (MHI). Fatigue is assessed using the Modified Fatigue Impact Scale (MFIS) score. We compared them with 100 healthy controls. RESULTS: There was a significant statistical difference between the MHI score and individual components of MHI. Overall, MHI scores in cases and controls were 79.41 and 93.31, respectively, with a P value of less than 0.0001. Computed scores for anxiety, depression, behavior control, and positive affect of COVID-19 survivors showed statistically significant differences as compared to healthy controls. There was a weak association between hospital stay duration and poor MHI scores. Fatigue was significantly worse in COVID-19 survivors, with a mean score of 6.93 in cases and 5.35 in controls, with a P value of 0.0001. This was a cross-sectional study evaluating psychiatric symptom scores, but not establishing the diagnosis. It is suggested that appropriate treatment and counseling for these symptoms should be done. CONCLUSIONS: Psychiatric symptoms and fatigue were significantly more common in COVID-19 patients after recovery from acute illness. It is a major contributing cause of morbidity other than organic complications of COVID-19 and requires attention in management.

Validity and reliability of Korean version of Modified Fatigue Impact Scale (MFIS) for Korean patients with multiple sclerosis.

BACKGROUND: To determine the validity and reliability of the Korean version of the Modified Fatigue Impact Scale (MFIS-K) questionnaire for patients with multiple sclerosis (MS). METHODS: We prospectively enrolled 52 patients with MS and 102 healthy controls. Subjects were asked to complete the Korean version of Fatigue Severity Scale (FSS) and MFIS-K. To evaluate sleep quality, depression, pain, and quality of life, patients completed the Pittsburgh Sleep Quality Index (PSQI), the Beck Depression Scale II (BDI), the Brief Pain Inventory (BPI), and the Short Form 36 Health Survey (SF-36). RESULTS: It was demonstrated that MFIS-K has appropriate construct validity with distinctive 3 factors (cognitive, physical, and psychosocial). The criterion validity was also confirmed with the total score and the factor scores of the patients with MS, which were all significantly higher than those of healthy controls. Convergent validity of the MFIS-K was verified with the correlations with Fatigue Severity Scale (FSS) and other concurrent measures of sleep disturbances, depression, pain, and limitations in activities due to health problems. Furthermore, the internal consistency, temporal stability, and score consistency of the MFIS-K turned out acceptable. DISCUSSION: Our results indicate that the Korean version of MFIS is a valid and reliable scale to assess fatigue in the Korean MS population.

Influence of Transcranial Direct Current Stimulation and Exercise on Fatigue and Quality of Life in Multiple Sclerosis.

BACKGROUND: Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system that leads to a great deterioration in the quality of life. OBJECTIVE: We aimed to assess the effectiveness of two individual programs, one based on transcranial direct current stimulation (tDCS) and another based on the effect of physical exercise on fatigue and quality of life in patients with MS. METHODS: A total of 12 patients with relapsing-remitting and progressive secondary MS participated. Fatigue and quality of life were assessed before and after intervention. The exercise program and tDCS were carried out over a 4-week period, with a washout period of 5 months. RESULTS: The results show significant improvements in the different quality of life subscales after the application of tDCS, activities of daily living (r = 0.625; p = 0.037) (g = 0.465), psychological well-being (r = 0.856; p = 0.004) (g = 0.727) and coping (r = 0.904; p = 0.18) (g = 0.376), and in those after the application of exercise, activities of daily living (r = 0.853; p = 0.003) (g = 0.570) and psychological well-being (r = 0.693; p = 0.041) (g = 0.417). After the application of both therapies, more than 50% of the subjects did not have a positive fatigue score on the MFIS scale. CONCLUSION: The major findings suggest that the application of both therapies produces a beneficial effect with significant improvements in the quality of life of this sample.

Responsiveness and clinically meaningful changes for the Persian versions of the multiple sclerosis walking scale-12 and the modified fatigue impact scale following balance and gait rehabilitation in people with multiple sclerosis.

Background and Purpose: The Multiple sclerosis walking scale-12 (MSWS-12) and the Modified Fatigue Impact Scale (MFIS) are two popular outcome measures applied widely for assessing self-perceived walking ability and fatigue in people with multiple sclerosis (PwMS). The present study aimed to examine responsiveness and clinically meaningful changes for the Persian versions of the MSWS-12 and the MFIS following balance and gait rehabilitation in PwMS.Methods: Fifty-eight PwMS completed the Persian versions of the MSWS-12 and the MFIS before and after 4 weeks of balance and gait rehabilitation. Also, a 7-point global rating scale as an external criterion of change was completed at the post-intervention evaluation. The area under the receiver operating characteristics curve (AUC) and the correlation analysis were used to assess the responsiveness. In addition, the minimally clinically important change (MCIC) was measured to determine clinically meaningful changes following rehabilitation.Results: The AUC values for the Persian MSWS-12 and MFIS were 0.74 and 0.73, respectively. There were good to excellent correlations between the global rating scale of change and the Persian MSWS-12 (Gamma = 0.77) also MFIS (Gamma = 0.80) change scores (p = .001). Moreover, the MCICs of 7.5 and 4 points were obtained for the Persian MSWS-12 and MFIS, respectively.Conclusion: The Persian versions of the MSWS-12 and the MFIS were responsive outcome measures for monitoring changes in walking and fatigue after balance and gait rehabilitation in PwMS. The calculation of MCIC values would enhance the interpretation of changes in clinical and research settings.

A quick assessment of reliable change in fatigue: Reliable change indices of the modified fatigue impact scale - 5 item (MFIS-5).

BACKGROUND: Reliably monitoring changes in fatigue is an ongoing concern. OBJECTIVE: Evaluate reliable change using the Modified Fatigue Impact Scale 5-item version (MFIS-5) in people with MS (PwMS). METHODS: The MFIS-5 was administered at three time points in 157 PwMS. Test-retest reliability and reliable change scores were calculated at the 0.70, 0.80, 0.90, and 0.95 confidence intervals. RESULTS: Difference scores of 3, 4, 5, and 6 represent statistically meaningful change at the 0.70, 0.80, 0.90, and 0.95 confidence intervals, respectively. CONCLUSION: Cut points derived from this study and prior work can help reliably assess changes in fatigue over time.

Psychometric properties of an Arabic translation of the modified fatigue impact scale in patients with multiple sclerosis.

PURPOSE: To translate and validate the modified fatigue impact scale into Arabic (MFIS-A) in patients with multiple sclerosis (MS). METHODS: A total of 116 patients with relapsing remitting MS and 59 healthy participants were recruited. Fifty patients filled the MFIS-A twice with one week difference. Reliability was assessed by measuring Cronbach's α and intraclass correlation coefficient (ICC). The MFIS-A was correlated with the fatigue severity scale (FSS), the vitality domain of the Short Form 36 (SF-36V), the fatigue visual analogue scale (VAS-F), and the Beck Depression Inventory II (BDI-II) to assess validity. Dimensionality of the MFIS-A was investigated. A receiver operating characteristic (ROC) curve analysis was done and specificity and sensitivity were calculated. RESULTS: Factor analysis (based on 116 patients) revealed that the MFIS-A consists of two subscales: the physical/social and the cognitive subscales. The MFIS-A showed excellent test-retest reliability (ICC = 0.920) and internal consistency (Cronbach's α = 0.968). The minimal detectable change with 95% confidence interval was 14.68 (32.0%). The MFIS-A showed strong positive correlation with FSS and BDI-II, moderate positive correlation with VAS-F, negative moderate correlation with SF-36V, and weak correlation with EDSS. The MFIS-A differentiated healthy participants from patients with 79.3% sensitivity and 89.8% specificity. CONCLUSIONS: The MFIS-A showed good validity and reliability indicating its usefulness as an assessment measure for patients with MS.IMPLICATIONS FOR REHABILITATIONMFIS-A is a valid and reliable tool for fatigue evaluation for patients with relapsing remitting MS.The optimal cutoff scores of the total MFIS-A, the physical/social, and cognitive subscales which indicate fatigue are 35.5, 18.5, and 15.5, respectively.Changes of 14.68 or more points may indicate a clinically important change (a true change) in fatigue in patients with MS.

Tired of not knowing what that fatigue score means? Normative data of the Modified Fatigue Impact Scale (MFIS).

BACKGROUND: The Modified Fatigue Impact Scale (MFIS) is one of the most common self-report measures used to assess fatigue in multiple sclerosis (MS). Despite its widespread use, there are no existing normative data for the MFIS. OBJECTIVE: The present investigation aimed to develop normative data for the MFIS in a large community sample, stratified by age, gender, and education and to compare the derived new cutoffs to an existing cutoff. METHODS: A total of 675 healthy individuals, stratified by age, gender, and education completed the MFIS. After the removal of 19 outliers, the final sample consisted of 656 individuals. Archival data of 540 individuals with MS who completed the MFIS were also included to analyze the utility of the new cutoffs. RESULTS: There were no main effects on the MFIS for gender. However, there were main effects for age and education. Specifically, younger cohorts (25-34 and 35-44) reported less physical fatigue compared to the two oldest cohorts (55-64 and 65-74). Similar effects were found for total MFIS fatigue with individuals aged 55-64 reporting greater overall fatigue than 35-44 year olds. Finally, 18-24 year olds reported significantly higher levels of cognitive fatigue compared to 35-44 and 65-74 aged cohorts. No other effects were observed for age. Individuals with higher education consistently reported less fatigue. Subsequent analyses also revealed an interaction effect for age x gender. When examining the age x gender interaction, women age 18-24 reported significantly greater levels of physical, cognitive, psychosocial, and total fatigue than their male counterparts. In contrast, men aged 65-74 reported greater physical, cognitive, and total fatigue than women their age. Comparisons of the existing cutoff of the MFIS to the new age, gender, and education specific cutoffs found either comparable or slightly higher rates of fatigue with the latter. CONCLUSION: Based on these findings, updated normative data and age, gender, and education specific cutoffs are provided. Utilization of these updated norms will result in a more accurate assessment of fatigue and will be valuable for those conducting research and/or clinical practice with individual with MS.

Rationing of Nursing Care in Intensive Care Units.

The nursing practice refers to a wide range of tasks and responsibilities. In a situation where there is a problem of limited resources, nurses are forced to ration the patient's care-that is, minimize and skip some tasks. The main purpose of this work was to assess the rationing level of nursing care among staff in the intensive care units. METHODS: The research included 150 anaesthesiological nurses in the Silesian Region in Poland. The research was conducted from July to October 2019 using the standardized Perceived Implicit Rationing of Nursing Care (PRINCA) questionnaire on rationing nursing care, assessing the quality of patient care, and job satisfaction. The Modified Fatigue Impact Scale (MFIS) standardized questionnaire was used to assess the level of fatigue of respondents in the physical, cognitive, and psychosocial spheres. RESULTS: Sociodemographic factors, such as gender, age, place of residence, education, seniority, and type of employment were not found to affect the rationing level of nursing care in the intensive care unit. The average quality of patient care was 6.05/10 points, while the average job satisfaction rating was 7.13/10 points. Analysis of the MFIS questionnaire showed that respondents experienced fatigue between "rare" and "sometimes", and nursing staff fatigue was the main factor for rationing care. CONCLUSIONS: The higher the level of fatigue, the greater the rationing of care and the less satisfaction from work.

Minimally important difference of the fatigue severity scale and modified fatigue impact scale in people with multiple sclerosis.

BACKGROUND: Fatigue is a common and debilitating symptom of Multiple Sclerosis (MS); however, it is unknown what constitutes a clinically significant change in fatigue. Establishing the minimally important difference (MID) of fatigue outcome measures can inform the interpretation of changes in fatigue by estimating the level of change that is considered clinically relevant. AIM: Determine the MID for the Fatigue Severity Scale (FSS) and Modified Fatigue Impact Scale (MFIS) in people with MS. METHODS: This cross-sectional study collected information on self-reported fatigue (FSS and MFIS) and quality of life (EQ-5D and MS Impact Scale 29) through an online survey. Anchor-based methods were used to estimate MID, and ordinal logistic regression models were used to determine the difference in fatigue that would predict a significant effect on quality of life. RESULTS: 365 people with MS (81.9% female, 69.3% relapsing-remitting MS, mean age 46.2 ±â€¯11.6 years, mean time since diagnosis 9.6 ±â€¯8.7 years) responded to the survey. MID estimates for the FSS and MFIS ranged from 0.45-0.88 and 3.86-8.11 respectively, accounting for 6.4-12.6% of maximum FSS score and 4.6-9.7% of maximum MFIS score. CONCLUSIONS: MID estimates derived from this study indicate that a difference of at least 0.45 points on the FSS or 4 points on the MFIS constitutes a clinically significant difference in fatigue. Therefore, these estimates represent a threshold value which can be used to interpret changes in the FSS and MFIS over time or in response to an intervention.

Uncovering the association between fatigue and fatigability in multiple sclerosis using cognitive control.

BACKGROUND: Fatigue and cognitive dysfunction are two common symptoms experienced by patients with multiple sclerosis (MS). The relationship between subjective and objective fatigue (fatigability) in MS is poorly understood. Cognitive control tasks might be more conducive to fatigability and more likely to show associations between subjective and objective cognitive fatigue in MS. OBJECTIVE: To study the association between objective fatigability, as induced by a cognitive control task called the Blocked Cyclic Naming Task (BCNT), subjective fatigue and baseline cognitive functioning in patients with MS. METHODS: Twenty-one patients with MS completed baseline questions about their disease, the Montreal Cognitive Assessment (MoCA) battery and self-reported questionnaires on trait fatigue, sleep and depression. Disability was captured using the expanded disability status scale (EDSS). Participants then performed the BCNT and were asked about their level of state momentary fatigue before and after the BCNT. The BCNT consists of several blocks of either related or unrelated pictures that participants name as quickly as possible. The pictures cycled 4 times in each block and the difference in the response times (RTs) between related and unrelated blocks was captured. Data were analyzed using repeated measures analysis of variance and Pearson correlations. RESULTS: MS participants' performance declined for the related, but not unrelated blocks. The difference in RTs between related and unrelated conditions increased with repetition across cycles (p < 0.001). Participants also showed objective fatigability with less repetition priming (p = 0.02) in the 4th quarter and with greater differences between related and unrelated conditions in the later part of the task. Objective fatigability was strongly associated with participants' assessment of their level of momentary state fatigue (r = 0.612, p = 0.007). CONCLUSION: Using the appropriate tools, this study showed an association between subjective and objective cognitive fatigue in people with MS. The BCNT and cognitive control are useful tools in assessing patients with MS and should be explored in future, larger studies in this population.

Validation of the Modified Fatigue Impact Scale and the relationships among fatigue, pain and serum interleukin-6 levels in patients with neuromyelitis optica spectrum disorder.

Fatigue and pain are disabling symptoms in patients with neuromyelitis optica spectrum disorder (NMOSD). The Modified Fatigue Impact Scale (MFIS) has not yet been validated in patients with NMOSD, and anti-interleukin-6 (IL-6) receptor antibody was reported to decrease pain and fatigue in patients with NMOSD. The aim of this study was to validate MFIS and to investigate the relationships among fatigue, pain and serum IL-6 levels in patients with NMOSD. MFIS and the Multidimensional Fatigue Inventory (MFI), an established scale for fatigue, were administered to patients with NMOSD and age- and sex-matched healthy controls (HCs). The Pain Effects Scale score and serum IL-6 levels were also measured in patients with NMOSD. Correlations among clinical characteristics, laboratory data and each score were investigated. To validate MFIS in patients with NMOSD, MFIS was administered twice within 4days from the first administration. Fifty-one patients answered the first MFIS, and 26 patients answered the second MFIS. There was no difference between the first and second MFIS scores. Patients with NMOSD had higher MFIS and MFI scores than HCs. No correlations were observed between serum IL-6 levels and either score. MFIS was validated in patients with NMOSD. Serum IL-6 levels may not be involved in the pathogenesis of fatigue and pain in patients with NMOSD.

Minimal clinically important difference of the Modified Fatigue Impact Scale in Parkinson's disease.

OBJECTIVE: Fatigue is a common and debilitating symptom of Parkinson's disease (PD) with no evidence-based treatments. While several fatigue scales are partially validated in PD the minimal clinically important difference (MCID) is unknown for any scale but is an important psychometric value to design and interpret therapeutic trials. We thus sought to determine the MCID for the Modified Fatigue Impact Scale (MFIS). METHODS: This is a secondary data analysis from 94 PD participants in an acupuncture trial for PD fatigue. Standard psychometric approaches were used to establish validity and an anchor-based approach was used to determine the MCID. RESULTS: The MFIS demonstrated good concurrent validity with other outcome measures and high internal consistency. MCIDs values were found to be 13.8, 6.8 and 6.2 for the MFIS total, MFIS cognitive, and MFIS physical subscores respectively. CONCLUSIONS: The MFIS is a valid multidimensional measure of fatigue in PD with demonstrable MCID.