Validity of the Symbol Digit Modalities Test as a cognition performance outcome measure for multiple sclerosis

Study protocol of a randomized controlled trial comparing backward walking to forward walking training on balance in multiple sclerosis: The TRAIN-MS trial

Balance impairment and accidental falls are a pervasive challenge faced by persons with multiple sclerosis (PwMS), significantly impacting their quality of life. While exercise has proven to be an effective intervention for improving mobility and functioning in PwMS, current exercise approaches predominantly emphasize forward walking (FW) and balance training, with variable improvements in balance and fall rates. Backward walking (BW) has emerged as a promising intervention modality for enhancing mobility and strength outcomes; however, significant gaps remain. Specifically, there is limited knowledge about the efficacy of BW interventions on outcomes such as static, anticipatory, and reactive balance, balance confidence, falls, and cognition. This randomized controlled trial aims to determine the feasibility, acceptability, and impact of 8-weeks of backward walking training (TRAIN-BW) as compared to forward walking training (TRAIN-FW). Ninety individuals with MS with self-reported walking dysfunction or ≥ 2 falls in the past 6 months will be randomized in blocks, stratified by sex and disease severity to either the TRAIN-BW or TRAIN-FW intervention groups. Adherence and retention rates will be used to determine feasibility and the Client Satisfaction Questionnaire will be used to assess acceptability. The primary outcomes will be static, anticipatory, and reactive balance. Secondary outcomes include walking velocity, balance confidence, concern about falling, cognition, physical activity, and fall rates measured prospectively for 6 months after post-testing. Additionally, the extent to which cognitive functioning influences response to intervention will be examined. Backward walking training may be an innovative intervention to address balance impairments and falls in persons with MS.

Combined use of the Montreal Cognitive Assessment and Symbol Digit Modalities Test improves neurocognitive screening accuracy after cardiac arrest: A validation sub-study of the TTM2 trial

AIM

To assess the merit of clinical assessment tools in a neurocognitive screening following out-of-hospital cardiac arrest (OHCA).

METHODS

The neurocognitive screening that was evaluated included the performance-based Montreal Cognitive Assessment (MoCA) and Symbol Digit Modalities Test (SDMT), the patient-reported Two Simple Questions (TSQ) and the observer-reported Informant Questionnaire on Cognitive Decline in the Elderly-Cardiac Arrest (IQCODE-CA). These instruments were administered at 6-months in the Targeted Hypothermia versus Targeted Normothermia after Out-of-Hospital Cardiac Arrest (TTM2) trial. We used a comprehensive neuropsychological test battery from a TTM2 trial sub-study as a gold standard to evaluate the sensitivity and specificity of the neurocognitive screening.

RESULTS

In our cohort of 108 OHCA survivors (median age = 62, 88% male), the most favourable cut-off scores were: MoCA <26; SDMT z ≤-1; IQCODE-CA ≥3.04. The MoCA (sensitivity 0.64, specificity 0.85) and SDMT (sensitivity 0.59, specificity 0.83) had a higher classification accuracy than the TSQ (sensitivity 0.28, specificity 0.74) and IQCODE-CA (sensitivity 0.42, specificity 0.60). When using the cut-points for MoCA or SDMT in combination to identify neurocognitive impairment, sensitivity improved (0.74, specificity 0.81), area under the curve = 0.77, 95% CI [0.69, 0.85]. The most common unidentified impairments were within the episodic memory and executive functions domains, with fewer false negative cases on the MoCA or SDMT combined.

CONCLUSION

The MoCA and SDMT have acceptable diagnostic accuracy for screening for neurocognitive impairment in an OHCA population, and when used in combination the sensitivity improves. Patient and observer-reports correspond poorly with neurocognitive performance.

CLINICALTRIALS

gov Identifier: NCT03543371.

Clinical characteristics and impact on patient-reported outcomes and quality of life of people with ambulatory secondary progressive multiple sclerosis: Discover study

BACKGROUND

People with secondary progressive multiple sclerosis (pwSPMS) experience increasing disability, which impacts negatively on their health-related quality of life (HRQoL). Our aims were to assess the impact of secondary progressive multiple sclerosis (SPMS) on functional status and HRQoL and describe the clinical profile in this population.

METHODS

DISCOVER is an observational, cross-sectional, multicenter study with retrospective data collection in real-world clinical practice in Spain. Sociodemographic and clinical variables, functional and cognitive scales, patient-reported outcomes (PROs), and direct healthcare, and non-healthcare and indirect costs were collected.

RESULTS

A total of 297 evaluable pwSPMS with a EDSS score between 3-6.5 participated: 62.3 % were female and 18.9 % had active SPMS. At the study visit, 77 % of them presented an Expanded Disability Scale Score (EDSS) of 6-6.5. Nearly 40 % did not receive any disease-modifying treatment. Regarding the working situation, 61.6 % were inactive due to disability. PROs: 99.3 % showed mobility impairment in EuroQoL-5 Dimensions-5 Levels, and about 60 % reported physical impact on the Multiple Sclerosis Impact Scale-29. Fatigue was present in 76.1 %, and almost 40 % reported anxiety or depression. The Symbol Digit Modalities Test was used to assess cognitive impairment; 80 % of the patients were below the mean score. Participants who presented relapses two years before and had high EDSS scores had a more negative impact on HRQoL. PwSPMS with a negative impact on HRQoL presented a higher cost burden, primarily due to indirect costs.

CONCLUSIONS

PwSPMS experience a negative impact on their HRQoL, with a high physical impact, fatigue, cognitive impairment, and a high burden of indirect costs.

Cladribine effects on patient-reported outcomes and their clinical and biometric correlates in highly active relapsing multiple sclerosis at first switch: the observational, multicenter, prospective, phase IV CLADFIT-MS study

Patient-reported outcomes (PROs) are essential for understanding the effects of MS and its treatments on patients' lives; they play an important role in multiple sclerosis (MS) research and practice. We present the protocol for an observational study to prospectively assess the effect of cladribine tablets on PROs and their correlation to disability and physical activity in adults with highly active relapsing MS switching from a first disease modifying drug (DMD) to cladribine tablets in routine clinical practice at study sites in Italy. The primary objective will be to evaluate changes from baseline in the impact of highly active MS on self-assessed physical functioning 52 weeks after the switch to cladribine tablets using the Multiple Sclerosis Impact Scale-29 (MSIS-29). Secondary objectives will include self-assessed psychological impact of highly active MS in daily life and general health after the switch to cladribine tablets as well as changes in cognitive function, anxiety, and depression symptoms. Additional PRO measures will include the Hospital Anxiety and Depression Scale (HADS), the EuroQoL 5-Dimension 5-Level (EQ-5D-5L), the Work Productivity and Activity Impairment Questionnaire: Multiple Sclerosis (WPAI:MS), and the Patient-Reported Outcomes Measurement Information System (PROMIS). Wearable devices will acquire activity data (step counts, walking speed, time asleep, and energy expenditure). Additional clinical, radiological, and laboratory data will be collected when available during routine management. The findings will complement data from controlled trials by providing insight from daily clinical practice into the effect of cladribine tablets on the patient's experience and self-assessed impact of treatment on daily life.

French consensus procedure for neuropsychological assessment in multiple sclerosis

Cognitive impairment is one of the invisible symptoms of Multiple sclerosis (MS), which could be associated with depression, unemployment, reduced social interaction, inability to drive, and compromised quality of life. Moreover, the presence of cognitive impairment can be considered as a long-term prognostic factor and in the follow-up of disability. So, cognitive assessment is a crucial element in clinical follow-up of patients with MS (pwMS). International recommendations mention the use of the Brief International Cognitive Assessment in MS (BICAMS). The BICAMS, that has been recently validated in French is a brief non-exhaustive assessment, developed as a short screening battery, hence needing other supplemented tests. The present paper aims to propose a consensus, approved by expert French consensus from the Cognition group of the SF-SEP (http://sfsep.org [Société Francophone de la Sclérose en Plaques]), for cognitive assessment of pwMS suggesting the tools that should be used in order to apprehend the other cognitive impairments that could appear in MS.

Long COVID Brain Fog Treatment: Findings from a Pilot Randomized Controlled Trial of Constraint-Induced Cognitive Therapy

Purpose

Long COVID brain fog is often disabling. Yet, no empirically-supported treatments exist. This study's objectives were to evaluate feasibility and efficacy, provisionally, of a new rehabilitation approach, Constraint-Induced Cognitive Therapy (CICT), for post-COVID-19 cognitive sequelae.

Design

Sixteen community-residents ≥ 3-months post-COVID-19 infection with mild cognitive impairment and dysfunction in instrumental activities of daily living (IADL) were enrolled. Participants were randomized to Immediate-CICT or treatment-as-usual (TAU) with crossover to CICT. CICT combined behavior change techniques modified from Constraint-Induced Movement Therapy with Speed of Processing Training, a computerized cognitive-training program. CICT was deemed feasible if (a) ≥80% of participants completed treatment, (b) the same found treatment highly satisfying and at most moderately difficult, and (c) <2 study-related, serious adverse-events occurred. The primary outcome was IADL performance in daily life (Canadian Occupational Performance Measure). Employment status and brain fog (Mental Clutter Scale) were also assessed.

Results

Fourteen completed Immediate-CICT (n=7) or TAU (n=7); two withdrew from TAU before their second testing session. Completers were [M (SD)]: 10 (7) months post-COVID; 51 (13) years old; 10 females, 4 males; 1 African American, 13 European American. All the feasibility benchmarks were met. Immediate-CICT, relative to TAU, produced very large improvements in IADL performance (M=3.7 points, p<.001, d=2.6) and brain fog (M=-4 points, p<.001, d=-2.9). Four of five non-retired Immediate-CICT participants returned-to-work post-treatment; no TAU participants did, p=.048.

Conclusions

CICT has promise for reducing brain fog, improving IADL, and promoting returning-to-work in adults with Long COVID. Findings warrant a large-scale RCT with an active-comparison group.

Cognitive function in severe progressive multiple sclerosis

Cognitive impairment is common in multiple sclerosis and negatively impacts quality of life. Cognitive status has yet to be described in people with severe progressive multiple sclerosis, in whom conventional neuropsychological testing is exceptionally difficult. The objective for the study was to characterize cognitive performance in severe progressive multiple sclerosis and compare them with age-, sex- and disease duration-matched less disabled people with multiple sclerosis using a specifically developed auditory, non-motor test of attention/cognitive processing speed-Auditory Test of Processing Speed. Also, we aimed to determine the relationship between cognitive performance and MRI-based outcomes in these matched cohorts. The Comprehensive Assessment of Severely Affected Multiple Sclerosis study was carried out at the University at Buffalo and the Boston Home, a skilled nursing facility in Dorchester, MA. Inclusion criteria were age 30-80 years and expanded disability status scale 3.0-6.5 for community-dwelling and 7.0-9.5 for skilled nursing facility people with multiple sclerosis. The cognitive assessment was performed using the Brief International Cognitive Assessment for Multiple Sclerosis consisting of Symbol Digit Modalities Test, Brief Visuospatial Memory Test-Revised, California Verbal Learning Test-2nd edition along with Auditory Test of Processing Speed, Paced Auditory Serial Addition Test-3 second and Controlled Oral Word Association Test. MRI scans were retrospectively collected and analysed for lesion and volumetric brain measurements. The rate of completion and performance of the cognitive tests was compared between the groups, and the relationship with MRI measures was determined using sex, age and years of education-adjusted linear regression models. Significantly greater percentage of the severe multiple sclerosis group completed Auditory Test of Processing Speed when compared with the current gold standard of Symbol Digit Modalities Test (93.2% versus 65.9%). Severe progressive multiple sclerosis had worse cognitive performance in all cognitive domains with greatest differences for cognitive processing speed (Symbol Digit Modalities Test > Paced Auditory Serial Addition Test-3 second > Auditory Test of Processing Speed, Cohen's d < 2.13, P < 0.001), learning and memory (Cohen's d < 1.1, P < 0.001) and language (Controlled Oral Word Association Test with Cohen's d = 0.97, P < 0.001). Multiple cognitive domains were significantly associated with lower thalamic (standardized β < 0.419, P < 0.006) and cortical (standardized β < 0.26, P < 0.031) volumes. Specially designed (auditory) cognitive processing speed tests may provide more sensitive screening of cognitive function in severe progressive multiple sclerosis. The cognitive profile of severe multiple sclerosis is proportional to their physical outcomes and best explained by decreased grey matter volume.

Cost and Quality of Life of Disability Progression in Multiple Sclerosis Beyond EDSS: Impact of Cognition, Fatigue, and Limb Impairment

BACKGROUND AND OBJECTIVE

Understanding the socioeconomic burden of multiple sclerosis (MS) is essential to inform policymakers and payers. Real-world studies have associated increasing costs and worsening quality of life (QoL) with disability progression. This study aims to further evaluate the impact of cognition, fatigue, upper and lower limb function (ULF, LLF) impairments, and disease progression per Expanded Disability Status Scale (EDSS) level, on costs and QoL.

METHODS

This was a cross-sectional cohort study including 20,988 patients from the German NeuroTransData MS registry from 2009 to 2019. QoL analyses were based on EQ-5D-5L. Cost analyses included indirect/direct medical and non-medical costs. Eight subgroups, ranging from 439 to 1812 patients were created based on presence of measures for disease progression (EDSS), cognition (Symbol Digit Modalities Test [SDMT]), fatigue (Modified Fatigue Impact 5-Item Scale [MFIS-5]), ULF (Nine-Hole Peg Test [9HPT]), and LLF (Timed 25-Foot Walk [T25FW]). Multivariable linear regression assessed the independent effect of each test's score on QoL and costs, while adjusting for EDSS and 12 other confounders.

RESULTS

Lower QoL was associated with decreasing cognition (p < 0.001), worsening ULF (p = 0.025), and increasing fatigue (p < 0.0001); however, the negative impact of LLF worsening on QoL was not statistically significant (p = 0.54). Higher costs were associated with decreasing cognition (p < 0.001), worsening of ULF (p = 0.0058) and LLF (p = 0.049), and increasing fatigue (p < 0.0001). Each 1-scale-step worsening function of SDMT, MFIS-5, 9HPT, and T25FW scores resulted in €170, €790, €330, and €520 higher costs, respectively. Modeling disability progression based on SDMT, MFIS-5, 9HPT, and T25FW scores as an interaction with EDSS strata found associations with lower QoL and higher costs at variable EDSS ranges.

CONCLUSIONS

Disease progression in MS measured by 9HPT, SDMT, and MFIS-5 had a significant negative impact on QoL and broad socioeconomic costs independent of EDSS. T25FW had a significant negative association with costs. Cognition, fatigue, ULF, and LLF have stronger impact on costs and QoL in patients with higher EDSS scores. Additional determinants of MS disability status, including SDMT, MFIS-5, 9HPT, and T25FW, should be considered for assessing cost effectiveness of novel therapeutics for MS.

Increased intraindividual variability (IIV) in reaction time is the earliest indicator of cognitive change in MS: A two-year observational study

Background

Cognitive decline in multiple sclerosis (MS) is common, but unpredictable, and increases with disease duration. As such, early detection of cognitive decline may improve the effectiveness of interventions. To that end, the Symbol Digit Modalities Test (SDMT) is effective in detecting slow processing speed as it relates to cognitive impairment, and intraindividual variability (IIV) observed in trials assessing continuous reaction time (RT) may be a useful indicator of early cognitive changes. Here, we will assess cognitive IIV changes in adults with early MS.

Methods

Adults with relapsing-remitting MS (RRMS), <11 years since diagnosis, were recruited nationally. Baseline and two-year follow-up assessments included Brief International Cognitive Assessment in MS (BICAMS) and Cogstate computerized tests. Intraindividual variability in RT was calculated from psychomotor tasks and data were age-normalized.

Results

A total of 44 of the 66 participants completed follow-up (mean age, 34.0 ± 5.5 years; 66 % female; mean disease duration, 4.1 ± 2.9 years; median Expanded Disability Status Scale (EDSS) score, 1.5 [0 to 6.0]). Participants were grouped by SDMT z-score median split. Groups did not differ in demographics or clinical features. The higher baseline SDMT group was faster (p = 0.05) in RT and less variable (lower IIV, p = 0.001). At the two-year follow-up, the higher SDMT group showed increased variability (p = 0.05) compared to the lower SDMT group, with no significant RT or BICAMS changes.

Conclusions

In early MS, higher SDMT performance at baseline is associated with less cognitive variability but may indicate susceptibility to increased variability over time, highlighting the importance of monitoring IIV for early cognitive changes.

Effects of virtual reality-based rehabilitation on cognitive function and mood in multiple sclerosis: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Multiple sclerosis (MS) is a disabling neurological disease that causes cognitive impairment and mental problems that occur in all MS phenotypes but are most common in patients with secondary progressive MS. Various degrees of cognitive impairment and mental health concerns are common among patients with MS (PwMS). Virtual reality (VR)-based rehabilitation is an innovative approach aimed at enhancing cognitive function and mood in PwMS. This study aims to perform a meta-analysis to assess the effects of VR-based rehabilitation on cognitive function and mood in PwMS.

METHODS

Using PubMed, Embase, the Cochrane Library, Web of Science, and the Physiotherapy Evidence Database (PEDro), a thorough database search was performed to identify randomized controlled trials (RCTs) examining the effects of VR on PwMS. Trials published until October 31, 2023, that satisfied our predetermined inclusion and exclusion criteria were included. Data were extracted, literature was examined, and the methodological quality of the included trials was assessed. StataSE version 16 was used for the meta-analysis.

RESULTS

Our meta-analysis included 461 patients from 10 RCTs.

PRIMARY OUTCOMES

The Montreal Cognitive Assessment (MoCA) (weighted mean difference [WMD]=1.93, 95 % confidence interval [CI]=0.51-3.36, P = 0.008, I² = 75.4 %) the Spatial Recall Test (SPART) (WMD=3.57, 95 % CI=1.65-5.50, P < 0.001, I² = 0 %), immediate recall (standard mean difference [SMD]=0.37, 95 % CI=0.10-0.64, P = 0.007, I² = 0 %) and delayed recall ([SMD]=0.30, 95 % CI=0.06-0.54, P = 0.013, I² = 35.4 %) showed improvements in comparison to the control group in terms of global cognitive function immediate recall, delayed recall, and visuospatial abilities.

SECONDARY OUTCOMES

Compared to the control group, anxiety improved (standard mean difference [SMD]=0.36, 95 % CI=0.10-0.62, P = 0.007, I² = 43.1 %). However, there were no significant differences in processing speed, attention, working memory or depression.

CONCLUSIONS

This systematic review provides valuable evidence for improving cognitive function and mood in PwMS through VR-based rehabilitation. In the future, VR-based rehabilitation may be a potential method to treat cognitive function and emotional symptoms of MS.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO; identifier: CRD42023474467.

Konectom™ cognitive processing speed test enables reliable remote, unsupervised cognitive assessment in people with multiple sclerosis: Exploring the use of substitution time as a novel digital outcome measure

BACKGROUND

The Konectom™ smartphone-based cognitive processing speed (CPS) test is designed to assess processing speed and account for impact of visuomotor function on performance.

OBJECTIVE

Evaluate reliability and validity of Konectom CPS Test, performed in clinic and remotely.

METHODS

Data were collected from people with multiple sclerosis (PwMS) aged 18-64 years and healthy control participants (HC) matched for age, sex, and education. Remote test-retest reliability (intraclass correlation coefficients, ICC); correlation with established clinical measures (Spearman correlation coefficients); group analyses between cognitively impaired/unimpaired PwMS; and influence of age, sex, education, and upper limb motor function on CPS Test measures were assessed.

RESULTS

Eighty PwMS and 66 HC participated. CPS Test measures from remote tests had good test-retest reliability (ICC of 0.67-0.87) and correlated with symbol digit modalities test (highest |ρ| = 0.80, p < 0.0001). Remote measures were stable (change from baseline < 5%) and correlated with MS disability (highest |ρ| = 0.39, p = 0.0004) measured by Expanded Disability Status Scale. CPS Test measures displayed sensitivity to cognitive impairment (highest d = 1.47). Demographics and motor function had the lowest impact on CPS Test substitution time, a measure accounting for visuomotor function.

CONCLUSION

Konectom CPS Test measures provide valid, reliable remote measurements of cognitive processing speed in PwMS.

Mobile Health App (DIGICOG-MS) for Self-Assessment of Cognitive Impairment in People With Multiple Sclerosis: Instrument Validation and Usability Study

BACKGROUND

Mobile health (mHealth) apps have proven useful for people with multiple sclerosis (MS). Thus, easy-to-use digital solutions are now strongly required to assess and monitor cognitive impairment, one of the most disturbing symptoms in MS that is experienced by almost 43% to 70% of people with MS. Therefore, we developed DIGICOG-MS (Digital assessment of Cognitive Impairment in Multiple Sclerosis), a smartphone- and tablet-based mHealth app to self-assess cognitive impairment in MS.

OBJECTIVE

This study aimed to test the validity and usability of the novel mHealth app with a sample of people with MS.

METHODS

DIGICOG-MS includes 4 digital tests assumed to evaluate the most affected cognitive domains in MS (visuospatial memory [VSM], verbal memory [VM], semantic fluency [SF], and information processing speed [IPS]) and inspired by traditional paper-based tests that assess the same cognitive functions (10/36 Spatial Recall Test, Rey Auditory Verbal Learning Test, Word List Generation, Symbol Digit Modalities Test). Participants were asked to complete both digital and traditional assessments in 2 separate sessions. Convergent validity was analyzed using the Pearson correlation coefficient to determine the strength of the associations between digital and traditional tests. To test the app's reliability, the agreement between 2 repeated measurements was assessed using intraclass correlation coefficients (ICCs). Usability of DIGICOG-MS was evaluated using the System Usability Scale (SUS) and mHealth App Usability Questionnaire (MAUQ) administered at the conclusion of the digital session.

RESULTS

The final sample consisted of 92 people with MS (60 women) followed as outpatients at the Italian Multiple Sclerosis Society (AISM) Rehabilitation Service of Genoa (Italy). They had a mean age of 51.38 (SD 11.36) years, education duration of 13.07 (SD 2.74) years, disease duration of 12.91 (SD 9.51) years, and a disability level (Expanded Disability Status Scale) of 3.58 (SD 1.75). Relapsing-remitting MS was most common (68/92, 74%), followed by secondary progressive (15/92, 16%) and primary progressive (9/92, 10%) courses. Pearson correlation analyses indicated significantly strong correlations for VSM, VM, SF, and IPS (all P<.001), with r values ranging from 0.58 to 0.78 for all cognitive domains. Test-retest reliability of the mHealth app was excellent (ICCs>0.90) for VM and IPS and good for VSM and SF (ICCs>0.80). Moreover, the SUS score averaged 84.5 (SD 13.34), and the mean total MAUQ score was 104.02 (SD 17.69), suggesting that DIGICOG-MS was highly usable and well appreciated.

CONCLUSIONS

The DIGICOG-MS tests were strongly correlated with traditional paper-based evaluations. Furthermore, people with MS positively evaluated DIGICOG-MS, finding it highly usable. Since cognitive impairment poses major limitations for people with MS, these findings open new paths to deploy digital cognitive tests for MS and further support the use of a novel mHealth app for cognitive self-assessment by people with MS in clinical practice.

Disrupted hemodynamic response within dorsolateral prefrontal cortex during cognitive tasks among people with multiple sclerosis-related fatigue

INTRODUCTION

Mental fatigue is an early and enduring symptom in persons with autoimmune disease particularly multiple sclerosis (MS). Neuromodulation has emerged as a potential treatment although optimal cortical targets have yet to be determined. We aimed to examine cortical hemodynamic responses within bilateral dorsolateral prefrontal cortex (dlPFC) and frontopolar areas during single and dual cognitive tasks in persons with MS-related fatigue compared to matched controls.

METHODS

We recruited persons (15 MS and 12 age- and sex-matched controls) who did not have physical or cognitive impairment and were free from depressive symptoms. Functional near infrared spectroscopy (fNIRS) registered hemodynamic responses during the tasks. We calculated oxyhemoglobin peak, time-to-peak, coherence between channels (a potential marker of neurovascular coupling) and functional connectivity (z-score).

RESULTS

In MS, dlPFC demonstrated disrupted hemodynamic coherence during both single and dual tasks, as evidenced by non-significant and negative correlations between fNIRS channels. In MS, reduced coherence occurred in left dorsolateral PFC during the single task but occurred bilaterally as the task became more challenging. Functional connectivity was lower during dual compared to single tasks in the right dorsolateral PFC in both groups. Lower z-score was related to greater feelings of fatigue. Peak and time-to-peak hemodynamic response did not differ between groups or tasks.

CONCLUSIONS

Hemodynamic responses were inconsistent and disrupted in people with MS experiencing mental fatigue, which worsened as the task became more challenging. Our findings point to dlPFC, but not frontopolar areas, as a potential target for neuromodulation to treat cognitive fatigue.

Improvement of the thalamocortical white matter network in people with stable treated relapsing-remitting multiple sclerosis over time

Advanced imaging techniques (tractography) enable the mapping of white matter (WM) pathways and the understanding of brain connectivity patterns. We combined tractography with a network-based approach to examine WM microstructure on a network level in people with relapsing-remitting multiple sclerosis (pw-RRMS) and healthy controls (HCs) over 2 years. Seventy-six pw-RRMS matched with 43 HCs underwent clinical assessments and 3T MRI scans at baseline (BL) and 2-year follow-up (2-YFU). Probabilistic tractography was performed, accounting for the effect of lesions, producing connectomes of 25 million streamlines. Network differences in fibre density across pw-RRMS and HCs at BL and 2-YFU were quantified using network-based statistics (NBS). Longitudinal network differences in fibre density were quantified using NBS in pw-RRMS, and were tested for correlations with disability, cognition and fatigue scores. Widespread network reductions in fibre density were found in pw-RRMS compared with HCs at BL in cortical regions, with more reductions detected at 2-YFU. Pw-RRMS had reduced fibre density at BL in the thalamocortical network compared to 2-YFU. This effect appeared after correction for age, was robust across different thresholds, and did not correlate with lesion volume or disease duration. Pw-RRMS demonstrated a robust and long-distance improvement in the thalamocortical WM network, regardless of age, disease burden, duration or therapy, suggesting a potential locus of neuroplasticity in MS. This network's role over the disease's lifespan and its potential implications in prognosis and treatment warrants further investigation.

Evaluation of a self-administered iPad®-based processing speed assessment for people with multiple sclerosis in a clinical routine setting

BACKGROUND

Limited resources often hinder regular cognitive assessment of people with multiple sclerosis (pwMS) in standard clinical care. A self-administered iPad®-based cognitive screening-tool (Processing Speed Test; PST) might mitigate this problem.

OBJECTIVE

To evaluate the PST in clinical routine.

METHODS

We investigated the feasibility of the PST in both a quiet and a waiting room setting. We assessed the validity of the PST in comparison with the established Symbol Digit Modalities Test (SDMT). We explored associations between processing speed assessments and the Brief International Cognitive Assessment for MS (BICAMS), magnetic resonance imaging (MRI) parameters, and psychological factors. Additionally, we explored the ability of the PST to detect impairment in processing speed compared to the SDMT.

RESULTS

The PST was feasible in the waiting room setting. PST and SDMT correlated comparably with the BICAMS, MRI parameters, and psychological variables. Of 172 pwMS, 50 (30.8%) showed cognitive impairment according to the BICAMS; respective values were 47 (27.3%) for the SDMT and 9 (5.2%) for the PST.

CONCLUSIONS

The PST performed in a waiting room setting correlates strongly with established cognitive tests. It thus may be used to assess processing speed in a resource-efficient manner and complement cognitive assessment in clinical routine. Despite comparable validity of the PST and SDMT, we identified more pwMS with impaired processing speed using normative data of the SDMT compared to the PST and advise caution, that the common cut-off score of - 1.5 SD from the current PST is not appropriate in Europe.

The association of fear of falling and falls with sedentary behavior in people with multiple sclerosis

OBJECTIVE

Sedentary behavior, falls, and fear of falling (FoF) are specific concerns for people with MS (pwMS). Considering the relatively high incidence and potential linkage, it is surprising that this triple relationship has as yet not been extensively investigated in pwMS. Thus, the present study aimed to examine the correlates of sedentary behavior with FoF and falls in pwMS.

METHODS

Fifty pwMS, 30 women, were admitted to this cross-sectional study. Primary outcome measures included physical activity and sedentary behavior metrics measured by accelerometry, fall status, and FoF. Additional measures included mobility clinical tests, cognition, perceived fatigue, depression, and anxiety. The sample was divided into two subgroups according to the daily Metabolic Equivalent of Task (MET) rate scores; <1.5 was defined as sedentary, ≥1.5 were defined as non-sedentary. Multivariate analysis of variance and linear regression analyses assessed the relationships by using an alpha of 0.05.

RESULTS

Sixty-four percent of the sample were classified as sedentary. The sedentary subgroup reported more FoF than the non-sedentary subgroup (32.5 (S·D. = 11.3) vs. 29.9 (S.D. = 9.5); however, no differences were found in fall status between the subgroups. No differences were found for depression, anxiety, cognition, and perceived fatigue between the subgroups. Furthermore, according to the linear regression analysis, FoF explained 23.9% of the variance pertaining to the daily MET rate when controlling for age, gender, disease duration, and disability.

CONCLUSIONS

Clinicians are encouraged to incorporate the issue of FoF during standard management, which may represent an opportunity to improve care and reduce sedentary behavior in pwMS.

Adapting the Multiple Sclerosis Functional Composite for Telehealth Administration Using Videoconference Delivery: Methodological Considerations and Interrater Reliability

Objective

To describe the adaptations made and to examine interrater reliability and feasibility of administering a telehealth version of the Multiple Sclerosis Functional Composite (tele-MSFC).

Design

The Multiple Sclerosis Functional Composite (MSFC) is a commonly used, in-person clinical outcome assessment. It is composed of the timed 25-Foot Walk Test (T25FWT), Nine-Hole Peg Test (NHPT), and Paced Auditory Serial Addition Test (PASAT). The MSFC was adapted for videoconference administration as part of a larger clinical trial. One of the adaptations included administering a timed 12.5-Foot Walk Test (T12.5FWT) for participants who did not have adequate space in their homes for the T25FWT. Participants, examiners, and raters completed surveys online about their satisfaction and experience with tele-MSFC.

Setting

Participants underwent the tele-MSFC in their homes using a laptop or smartphone while examiners scored the tele-MSFC in real-time at a remote location.

Participants

Community-dwelling adults (n=61) with mild-to-moderate multiple sclerosis (MS) symptoms.

Interventions

Not applicable.

Main Outcome Measure

Tele-MSFC.

Results

Intraclass correlation coefficients (ICC) assessed interrater reliability between the examiner and 2 independent raters who later scored a recording of the tele-MSFC. Interrater reliability was excellent (ICC>0.90) for all tests, including the T12.5FWT. Participants were highly satisfied with tele-MSFC. However, challenges included adequate space for T25FWT, technical difficulties, and safety and privacy considerations of individuals with moderate impairments who were requested to have their caregivers present during testing.

Conclusion

The tele-MSFC is reliable and feasible to administer with adaptations for community-dwelling adults with mild to moderate MS symptoms. Further validation of T12.5FWT is needed.

Effects of photobiomodulation therapy on muscle function in individuals with multiple sclerosis

BACKGROUND

In people with multiple sclerosis (pwMS), muscle fatigue and weakness are common issues that can interfere with daily activities. Photobiomodulation therapy (PBMT), comprising light in a 600-1100 nm bandwidth, is a low-level laser therapy thought to improve muscle performance in non-disease populations, in part, by improving mitochondrial function and thus, might be beneficial in pwMS. Given this potential, we aimed to investigate the effects of PBMT on muscle performance in pwMS, both in the short-term and over an extended period.

METHODS

This study consisted of two parts with a randomized double-blind crossover design. In study I, muscle function was assessed in four sessions before and after PBMT in ambulatory pwMS (N = 17, F = 14) as follows: maximal voluntary contraction (MVC) and muscle fatigue of the right tibialis anterior (TA) muscle was compared at baseline and following a two-min submaximal fatiguing contraction. Then, PBMT was administered to the belly of TA muscle at different doses of energy of an active device (40 J, 80 J, 120 J) or placebo. The muscle function assessment was then repeated.

OUTCOME VARIABLES

muscle force recovery (%), muscle fatigue (%). Statistical tests included McNemar's exact test, Wilcoxon signed-rank test, and the Friedman test. In study II, a subgroup from study I (N = 12, F = 11) received individualized doses (i.e., best dose-effect observed in study I) of active, or placebo PBMT, which was administered on the TA muscle for two weeks. Muscle function assessments were performed pre- and post-PBMT in four sessions similar to study I.

OUTCOME VARIABLES

Baseline strength (N), endurance time (s), and muscle fatigue (%). The Wilcoxon signed-rank test was used for statistical analysis. Values are reported as mean (SD).

RESULTS

In study I, participants who received a high dose of PBMT showed significant improvement in force recovery (101.89 % (13.55 %)) compared to the placebo group (96.3 % (18.48 %); p = 0.03). Muscle fatigue did not significantly improve with either active PBMT or placebo. In study II, active PBMT resulted in a significant improvement in muscle strength compared to both the baseline (pre-PBMT = 162.70 N (37.52 N); post-PBMT = 185.56 N (33.95 N); p = 0.01) and the placebo group (active PBMT: mean-change = 22.87 N (23.67 N); placebo: mean-change = -4.12 N (31.95 N); p = 0.02). Endurance time and muscle fatigue did not show significant improvement with either active PBMT or placebo.

CONCLUSION

Our findings suggest that an individualized dose of PBMT might improve muscle performance, including force recovery and strength in individuals with mild-moderate MS. Therefore, PBMT might be a novel therapeutic modality, either as a standalone treatment or in combination with other interventions, to improve muscle performance in pwMS.

Discriminative ability of the original and short form of the Activities-specific Balance Confidence scale and its individual items for falls in people with multiple sclerosis

BACKGROUND

Balance confidence is an essential component of fall risk assessment in persons with multiple sclerosis (pwMS).

AIMS

The aims of this cross-sectional study were to 1) investigate the ability of the 16-item Activities-specific Balance Confidence scale (ABC-16), 6-item Activities-specific Balance Confidence scale (ABC-6), and each item of the ABC-16 for distinguishing fallers and 2) determine cutoff scores for these scales to discriminate fallers and non-fallers in pwMS.

METHODS

One hundred and fifty-six participants [fallers/non-fallers: 60 (38.5%)/96 (61.5%), median EDSS: 1.5] were enrolled. Balance confidence was assessed using the ABC-16 and ABC-6. The self-reported number of falls in the past three months was recorded. Descriptive assessments, including walking, balance, and cognition were performed. Logistic regression and receiver operating characteristic analyses were conducted to estimate the sensitivities and specificities of the ABC-16 and ABC-6.

RESULTS

Both the ABC-16 (AUC: 0.85) and ABC-6 (AUC: 0.84) had the discriminative ability for falls. Each item of the ABC-16 scale was a significantly related to falls [odds ratio (OR) range: 1.38 to 1.89]. Items 8 and 10 had the highest odds ratio (OR: 1.85; 95%CI: 1.47-2.33, OR: 1.89; 95%CI: 1.49-2.40; respectively). We found cutoff scores of ≤ 70 of 100 (sensitivity: 71.67, specificity: 86.46) and ≤ 65/100 (sensitivity: 76.67, specificity: 79.17) in discrimination between fallers and non-fallers for the ABC-16 and ABC-6, respectively.

CONCLUSION

Both original and short forms of the ABC scale are an efficient tool for discriminating fallers and non-fallers in pwMS. Although all items are related to falls, outdoor walking activities have the strongest associations with falls than other items.

Information processing speed and disease severity predict real-world ambulation in persons with multiple sclerosis

BACKGROUND

Impairments in real-world gait quality and quantity are multifaceted for individuals with multiple sclerosis (MS), encompassing mobility, cognition, and fear of falling. However, these factors are often examined independently, limiting insights into the combined contributions they make to real-world ambulation.

RESEARCH QUESTION

How do mobility, cognition, and fear of falling contribute to real-world gait quality and quantity in individuals with MS?

METHODS

Twenty individuals with MS underwent a series of cognitive assessments, including the Paced Auditory Serial Addition Test (PASAT), Symbol Digits Modalities Test (SDMT), Stroop Test, and the Selective Reminding Test (SRT). Participants also completed the Falls Efficacy Scale - International (FES-I) and walking impairment using the Patient Determined Disease Steps (PDDS). Following the in-lab session, participants wore an inertial sensor on their lower back and asked to go about their typical daily routines for three days. Metrics of gait speed, stride regularity, time spent walking, and total bouts were extracted from the real-world data.

RESULTS

Significant correlations were found between both real-world gait speed and stride regularity and the SDMT, FES-I, and PDDS. Backward linear regression analysis was conducted for gait speed and stride regularity, with PDDS and SDMT included in the final model for both metrics. These variables explained 63% of the variance in gait speed and 69% of the variance in stride regularity. Results were not significant for gait quantity after adjusting for age and sex.

SIGNIFICANCE

The study's results provide insight regarding the roles of cognition, walking impairment, and fear of falling on real-world ambulation. Deeper understanding of these contributions can inform the development of targeted interventions that aim to improve walking. Additionally, the absence of significant correlations between gait metrics, cognition, and fear of falling with gait quantity underscores the need for further research to identify factors that increased walking in this population.

Olfactory threshold as a biomarker of long-term relapse activity in multiple sclerosis

BACKGROUND

Olfactory threshold (OT) is a marker of short-term inflammatory activity in multiple sclerosis (MS).

OBJECTIVE

To investigate whether OT predicts long-term MS clinical disease course.

METHODS

This was a 6-year prospective longitudinal study on MS patients at the MS clinic Innsbruck. Clinical visits assessing the occurrence of relapses, Expanded Disability Status Scale (EDSS) scores, and disease-modifying treatment (DMT), were conducted biannually. OT testing was performed at baseline (BL), year 1 (Y1), year 2 (Y2) and year 6 (Y6), using the threshold subscore of the "Sniffin' Sticks" test. Cognitive function was assessed by the Symbol Digit Modalities Test.

RESULTS

Of 139 MS patients, 92 were eligible for Y6 follow-up. 68% experienced relapses, 53% EDSS worsening, 29% progression independent of relapse activity (PIRA) and 41% cognitive deterioration. OT scores were lower at BL, Y1 and Y2 in patients requiring DMT escalation. In multivariable analysis, higher OT scores at BL, Y1, Y2 and Y6 were associated with lower risk of relapse (hazard ratio, HR: 0.65-0.92) and EDSS worsening (HR: 0.86-0.89), while no associations were found for PIRA and cognitive deterioration.

CONCLUSIONS

OT is a potential surrogate marker for long-term inflammatory disease activity and DMT failure in MS.

Patterns of prospective memory errors differ in persons with multiple sclerosis

INTRODUCTION

Prospective memory (PM) deficits have been documented in multiple sclerosis (MS). This study aimed to explore the specific types of errors made by persons with MS (PwMS), including differences between PwMS and healthy controls (HC) and PwMS who do and do not have impairments in processing speed and/or verbal learning and memory.

METHOD

PwMS (n = 111) and HC (n = 75) completed the Memory for Intentions Test (MIST), an objective measure of PM that has five types of errors that can be coded (PM failure, task substitution, loss of content, loss of time, and random errors). The number and types of PM errors were calculated for the overall MIST and six subscales, which break down performance by types of delay (2-Minute and 15-Minute), cue (Time and Event), and response (Verbal and Action). Impairment was defined as performing < 1.5 SD on either the Symbol Digit Modalities Test (SDMT) or Rey Auditory Verbal Learning Test (RAVLT). Bivariate analyses were used to examine group differences, with post-hoc pairwise comparisons with Bonferroni corrections.

RESULTS

Nearly 93% of PwMS made at least one PM error, compared to 76% of HC (V = .24, p = .001). The most commonly made PM error by PwMS was loss of content errors (45.0%). PwMS made significantly more task substitution errors (26.4% vs. 7.6%, p < .001) and fewer loss of time errors (9.5% vs. 21.2%, p < .001) than HC. Impaired PwMS made more errors than non-impaired PwMS, specifically PM failures on time-based tasks.

CONCLUSIONS

PM errors are common in PwMS, particularly when there are longer delays and time-based cues. Not only do PwMS make more errors than demographically similar HC, but they exhibit different cognitive process failures.

Efficacy of erythropoietin as a neuroprotective agent in CKD-associated cognitive dysfunction: A literature systematic review

Patients with chronic kidney disease (CKD) often experience mild cognitive impairment and other neurocognitive disorders. Studies have shown that erythropoietin (EPO) and its receptor have neuroprotective effects in cell and animal models of nervous system disorders. Recombinant human EPO (rHuEPO), commonly used to treat anemia in CKD patients, could be a neuroprotective agent. In this systematic review, we aimed to assess the published studies investigating the cognitive benefits of rHuEPO treatment in individuals with reduced kidney function. We comprehensively searched Pubmed, Cochrane Library, Scopus, and Web of Science databases from 1990 to 2023. After selection, 24 studies were analyzed, considering study design, sample size, participant characteristics, intervention, and main findings. The collective results of these studies in CKD patients indicated that rHuEPO enhances brain function, improves performance on neuropsychological tests, and positively affects electroencephalography measurements. These findings suggest that rHuEPO could be a promising neuroprotective agent for managing CKD-related cognitive impairment.

Cognitive function influences cognitive-motor interference during dual task walking in multiple sclerosis

BACKGROUND

Both physical and cognitive impairments are common in people with multiple sclerosis (PwMS). Performing a cognitive task while walking (i.e., dual-task walking) can introduce cognitive-motor interference (CMI), resulting in changes in walking performance. The association between the levels of cognitive impairment and of CMI in MS remains unclear.

OBJECTIVES

To examine the association between cognitive functioning and differences in walking performance arise between single- and dual-task walking.

METHODS

Ninety-five PwMS performed self-preferred pace walking and dual-task walking. The gait parameters recorded were used to compute dual task costs (DTC) as a metric of CMI. Cognitive functioning was assessed using Match, an unsupervised test developed based on the Symbol Digit Modalities Test. Participants were categorized as higher (HCF) and lower cognitive functioning (LCF) based on a Match z-score < -1.5.

RESULTS

LCF group had elevated DTC for stride velocity, relative to the HCF group. Higher DTC for stride velocity was associated with lower cognition, as assessed by Match test.

CONCLUSION

The findings support the hypothesis that CMI is associated with cognitive functioning in PwMS.

Effects of Physical Therapy and Dalfampridine on Function and Quality of Life in Nonambulatory Individuals With Multiple Sclerosis: A Randomized Controlled Trial

BACKGROUND

Decreases in mobility, quality of life (QOL) and cognition are commonly seen in people with multiple sclerosis (MS). Physical therapy (PT) and exercise have been shown to improve many symptoms in ambulatory individuals with MS; however, evidence in nonambulatory people with MS is lacking. Dalfampridine is a US Food and Drug Administration-approved medication for MS that treats impaired ambulation by enhancing nerve conduction. To our knowledge, no study has examined the combined effect of PT and dalfampridine and very few studies have examined dalfampridine's effect on function in individuals with more progressive disease. The purpose of this study was to examine the effectiveness of PT combined with dalfampridine or a placebo on function, QOL, and cognition in nonambulatory individuals with MS. In addition, we explored the benefits of PT in all participants to increase the extremely limited research in this population.

METHODS

Adults with MS were randomly assigned to receive dalfampridine (n = 13) or placebo (n = 14) for 12 weeks in conjunction with PT treatment 2 times a week. Function, QOL, and cognition were assessed at baseline, 6 weeks, and 12 weeks.

RESULTS

There was a significant time × group interaction for the Multiple Sclerosis Quality of Life-54 favoring the placebo group. Both groups significantly improved on the 9-Hole Peg Test (left arm only), sitting lateral reach (right), transferring from wheelchair to mat, and repeated sit to stand.

CONCLUSIONS

The addition of dalfampridine to physical therapy did not improve function, QOL, or cognitive processing speed. Importantly, this study demonstrated an overall benefit in function and QOL with physical therapy 2 times a week for 12 weeks for nonambulatory individuals with MS.

Using Objective and Subjective Measures of Cognition to Predict Instrumental Activities of Daily Living Abilities in Multiple Sclerosis

BACKGROUND

Cognitive impairment, difficulty performing basic activities of daily living (ADLs) and instrumental ADLs (IADLs), depression, and fatigue are common among individuals with multiple sclerosis (MS). Some associations between these symptoms are known; however, many of their relationships remain unclear. This study investigated the contributions of subjective and objective cognition, depressive symptom severity, and fatigue on ADLs and IADLs.

METHODS

Participants (N = 217) were individuals with MS from a comprehensive MS center, participating in a larger study characterizing upper extremity function in MS. Outcome measures of ADL and IADL abilities were the Functional Status Index-Assistance (FSI-A) and Functional Status Index-Difficulty (FSI-D) and the Test D'évaluation Des Membres Supérieurs de Personnes Âgées (TEMPA). Predictors were objective cognition (Symbol Digit Modalities Test; SDMT), subjective cognition (Performance Scales©-Cognition; PS-C), depressive symptom severity (Center for Epidemiologic Studies Depression Scale; CES-D-10), and fatigue (Modified Fatigue Impact Scale; MFIS-5). Correlations were conducted, followed by hierarchal linear regressions. The SDMT and PS-C were entered into separate models.

RESULTS

After controlling for demographics, the SDMT significantly predicted the TEMPA and FSI-A, while the PS-C predicted only the FSI-D. The CES-D-10 predicted the FSI-D even after accounting for PS-C and SDMT, while the MFIS-5 only predicted the FSI-D when the SDMT was included. Neither the CES-D-10 nor MFIS-5 significantly predicted the FSI-A or TEMPA.

CONCLUSIONS

The way an individual with MS perceived their symptoms significantly contributed to their reported difficulty with functional tasks, while only their objective cognitive functioning predicted ADL and IADL performance and the level of assistance they would require.

Identifying and understanding cognitive profiles in multiple sclerosis: a role for visuospatial memory functioning

BACKGROUND

The heterogeneous nature of cognitive impairment in people with multiple sclerosis (PwMS) hampers understanding of the underlying mechanisms and developing patient-tailored interventions. We aim to identify and classify cognitive profiles in PwMS, comparing these to cognitive status (preserved versus impaired).

METHODS

We included 1213 PwMS (72% female, age 45.4 ± 10.7 years, 83% relapsing-remitting MS). Cognitive test scores were converted to Z-scores compared to healthy controls for the functions: attention, inhibition, information processing speed (IPS), verbal fluency and verbal/visuospatial memory. Concerning cognitive status, impaired cognition (CI) was defined as performing at Z ≤ - 1.5 SD on ≥ 2 functions. Cognitive profiles were constructed using latent profile analysis on all cognitive functions. Cognitive profiles or status was classified using gradient boosting decision trees, providing the importance of each feature (demographics, clinical, cognitive and psychological functioning) for the overall classification.

RESULTS

Six profiles were identified, showing variations in overall performance and specific deficits (attention, inhibition, IPS, verbal fluency, verbal memory and visuospatial memory). Across the profiles, IPS was the most impaired function (%CI most preserved profile, Profile 1 = 22.4%; %CI most impaired profile, Profile 6 = 76.6%). Cognitive impairment varied from 11.8% in Profile 1 to 95.3% in Profile 6. Of all cognitive functions, visuospatial memory was most important in classifying profiles and IPS the least (area under the curve (AUC) = 0.910). For cognitive status, IPS was the most important classifier (AUC = 0.997).

CONCLUSIONS

This study demonstrated that cognitive heterogeneity in MS reflects a continuum of cognitive severity, distinguishable by distinct cognitive profiles, primarily explained by variations in visuospatial memory functioning.

Impact of Acute Dopamine Replacement on Cognitive Function in Parkinson's Disease

BACKGROUND

PD causes striatal dopaminergic denervation in a posterior/dorsal to anterior/ventral gradient, leaving motor and associative cortico-striato-pallido-thalamic loops differentially susceptible to hyperdopaminergic effects with treatment. As the choice and titration of symptomatic PD medications are guided primarily by motor symptoms, it is important to understand their cognitive implications.

OBJECTIVE

To investigate the effects of acute dopaminergic medication administration on executive function in Parkinson's disease (PD).

METHODS

Participants with idiopathic PD were administered the oral Symbol Digit Modalities Test (SDMT; n = 181) and the Stroop test (n = 172) in the off-medication and "best on" medication states. ANCOVA was used to test for differences between off-medication and on-medication scores corrected for age and years of education.

RESULTS

After administration of symptomatic medications, scores worsened on the SDMT (F = 11.70, P < 0.001, d = -0.13), improved on the Stroop color (F = 26.89, P < 0.001, d = 0.184), word (F = 6.25, P = 0.013, d = 0.09), and color-word (F = 13.22, P < 0.001, d = 0.16) test components, and the Stroop difference and ratio-based interference scores did not significantly change. Longer disease duration correlated with lower scores on the SDMT, Stroop color, word, and color-word scores; however, longer disease duration and higher levodopa-equivalents correlated with higher Stroop difference-based interference scores.

CONCLUSIONS

Symptomatic medication differentially affects performance on two cognitive tests in PD. After acute treatment, core Stroop measures improved, Stroop interference was unchanged, and SDMT performance worsened, likely reflecting complex changes in processing speed and executive function related to acute treatment. When considering motor symptom therapies in PD, an individual's cognitive demands and expectations, especially regarding executive function, should be considered.

Thalamic atrophy and dysconnectivity are associated with cognitive impairment in a multi-center, clinical routine, real-word study of people with relapsing-remitting multiple sclerosis

BACKGROUND

Prior research has established a link between thalamic pathology and cognitive impairment (CI) in people with multiple sclerosis (pwMS). However, the translation of these findings to pwMS in everyday clinical settings has been insufficient.

OBJECTIVE

To assess which global and/or thalamic imaging biomarkers can be used to identify pwMS at risk for CI and cognitive worsening (CW) in a real-world setting.

METHODS

This was an international, multi-center (11 centers), longitudinal, retrospective, real-word study of people with relapsing-remitting MS (pwRRMS). Brain MRI exams acquired at baseline and follow-up were collected. Cognitive status was evaluated using the Symbol Digit Modalities Test (SDMT). Thalamic volume (TV) measurement was performed on T2-FLAIR, as well as on T1-WI, when available. Thalamic dysconnectivity, T2-lesion volume (T2-LV), and volumes of gray matter (GM), whole brain (WB) and lateral ventricles (LVV) were also assessed.

RESULTS

332 pwMS were followed for an average of 2.8 years. At baseline, T2-LV, LVV, TV and thalamic dysconnectivity on T2-FLAIR (p < 0.016), and WB, GM and TV volumes on T1-WI (p < 0.039) were significantly worse in 90 (27.1 %) CI vs. 242 (62.9 %) non-CI pwRRMS. Greater SDMT decline over the follow-up was associated with lower baseline TV on T2-FLAIR (standardized β = 0.203, p = 0.002) and greater thalamic dysconnectivity (standardized β = -0.14, p = 0.028) in a linear regression model.

CONCLUSIONS

PwRRMS with thalamic atrophy and worse thalamic dysconnectivity present more frequently with CI and experience greater CW over mid-term follow-up in a real-world setting.

Disrupted brain structural networks associated with depression and cognitive dysfunction in cerebral small vessel disease with microbleeds

Emerging evidence highlights cerebral microbleeds (CMBs) as hallmarks of cerebral small vessel disease (CSVD) underlying depression and cognitive dysfunction. This study aimed to reveal how depression and cognition-related white matter (WM) abnormalities are topologically presented, and the network-level structural disruptions associated with CMBs in CSVD. We used probabilistic diffusion tractography and graph theory to investigate brain WM network topology in CSVD patients with (n = 64, CSVD-c) and without (n = 138, CSVD-n) CMBs and 90 healthy controls. Then we evaluated the Pearson's correlations between disrupted network metrics and neuropsychological parameters. For global topology, the CSVD-c group exhibited significantly decreased global (Eglob) and local (Eloc) efficiency and increased shortest path length compared with the controls, while no significant difference was found between the CSVD-c and CSVD-n groups. For regional topology, although all groups showed highly similar hub distributions, compare with control group, the CSVD-c group exhibited significantly decreased nodal efficiency mainly in the bilateral supplementary motor area (SMA), median cingulate gyrus (DCG) and right orbital middle frontal gyrus, while the CSVD-n group showed significantly decreased nodal efficiency only in the right SMA. Notably, Eglob, Eloc and nodal efficiency of the right anterior cingulate gyrus, DCG, middle temporal gyrus and left insula showed significantly negative correlations with depression score, significantly positive correlations with Rey auditory verbal learning test and symbol digit modalities test scores in CSVD-n group, as well as significantly negative correlations with Stroop color-word test scores in CSVD-c group. The WM networks of CSVD patients are characterized by decreased global integration and local specialization, and decreased nodal efficiency highly related to depression and cognitive dysfunction in the attention, default mode network and sensorimotor regions. These findings provide new insight into the neurobiological mechanisms of CSVD and concomitant affective and cognitive disorders.

Functional gradients reveal cortical hierarchy changes in multiple sclerosis

Functional gradient (FG) analysis represents an increasingly popular methodological perspective for investigating brain hierarchical organization but whether and how network hierarchy changes concomitant with functional connectivity alterations in multiple sclerosis (MS) has remained elusive. Here, we analyzed FG components to uncover possible alterations in cortical hierarchy using resting-state functional MRI (rs-fMRI) data acquired in 122 MS patients and 97 healthy control (HC) subjects. Cortical hierarchy was assessed by deriving regional FG scores from rs-fMRI connectivity matrices using a functional parcellation of the cerebral cortex. The FG analysis identified a primary (visual-to-sensorimotor) and a secondary (sensory-to-transmodal) component. Results showed a significant alteration in cortical hierarchy as indexed by regional changes in FG scores in MS patients within the sensorimotor network and a compression (i.e., a reduced standard deviation across all cortical parcels) of the sensory-transmodal gradient axis, suggesting disrupted segregation between sensory and cognitive processing. Moreover, FG scores within limbic and default mode networks were significantly correlated (ρ = 0.30 $$ \rho =0.30 $$ , p < .005 after Bonferroni correction for both) with the symbol digit modality test (SDMT) score, a measure of information processing speed commonly used in MS neuropsychological assessments. Finally, leveraging supervised machine learning, we tested the predictive value of network-level FG features, highlighting the prominent role of the FG scores within the default mode network in the accurate prediction of SDMT scores in MS patients (average mean absolute error of 1.22 ± 0.07 points on a hold-out set of 24 patients). Our work provides a comprehensive evaluation of FG alterations in MS, shedding light on the hierarchical organization of the MS brain and suggesting that FG connectivity analysis can be regarded as a valuable approach in rs-fMRI studies across different MS populations.

Predictive value of retinal atrophy for cognitive decline across disease duration in multiple sclerosis

BACKGROUND

We investigated the association between changes in retinal thickness and cognition in people with MS (PwMS), exploring the predictive value of optical coherence tomography (OCT) markers of neuroaxonal damage for global cognitive decline at different periods of disease.

METHOD

We quantified the peripapillary retinal nerve fibre (pRFNL) and ganglion cell-inner plexiform (GCIPL) layers thicknesses of 207 PwMS and performed neuropsychological evaluations. The cohort was divided based on disease duration (≤5 years or >5 years). We studied associations between changes in OCT and cognition over time, and assessed the risk of cognitive decline of a pRFNL≤88 µm or GCIPL≤77 µm and its predictive value.

RESULTS

Changes in pRFNL and GCIPL thickness over 3.2 years were associated with evolution of cognitive scores, in the entire cohort and in patients with more than 5 years of disease (p<0.01). Changes in cognition were related to less use of disease-modifying drugs, but not OCT metrics in PwMS within 5 years of onset. A pRFNL≤88 µm was associated with earlier cognitive disability (3.7 vs 9.9 years) and higher risk of cognitive deterioration (HR=1.64, p=0.022). A GCIPL≤77 µm was not associated with a higher risk of cognitive decline, but a trend was observed at ≤91.5 µm in PwMS with longer disease (HR=1.81, p=0.061).

CONCLUSIONS

The progressive retinal thinning is related to cognitive decline, indicating that cognitive dysfunction is a late manifestation of accumulated neuroaxonal damage. Quantifying the pRFNL aids in identifying individuals at risk of cognitive dysfunction.

Prospective observational study to evaluate treatment satisfaction and effectiveness in patients with relapsing multiple sclerosis starting cladribine tablets (CLADREAL) in Italy

Disease-modifying therapies (DMTs) for multiple sclerosis (MS) reduce relapse frequency, magnetic resonance imaging (MRI) activity, and slow disability progression. Numerous DMTs are approved for relapsing forms of MS although real-world data on patient-reported outcomes (PROs) and quality of life (QoL) are needed to inform treatment choice. Immune reconstitution therapy with cladribine tablets is a highly effective treatment for relapsing MS (RMS). We present the protocol for an observational study to prospectively assess the effectiveness of cladribine tablets on clinical and MRI parameters as well as on PROs, including treatment satisfaction, QoL, sleep quality, self-perceived health, fatigue, and physical function. Enrolled patients at study sites in Italy will be adults with RMS (including relapsing-remitting and active secondary progressive MS) who are either treatment naïve or have received at least one first-line disease modifying DMT or no more than one second-line DMT. The primary objective will be change in global treatment satisfaction measured with the Treatment Satisfaction Questionnaire for Medication Version 1.4 approximately 24 months after initiating cladribine tablets in patients switching from previous DMTs. Secondary objectives will include global treatment satisfaction at earlier timepoints, will comprise treatment naïve patients, and will quantify treatment effectiveness and tolerability. We will also assess relapses, disability progression, MRI activity, and other PROs at approximately 12 and 24 months. The findings will provide insight from daily clinical practice into the patient's experience to complement data from controlled trials and inform treatment choice. EU PAS Registration Number EUPAS49334 filed 17/10/2022.

A comparative study of fatigue and processing speed in patients with multiple sclerosis treated with natalizumab or rituximab

Background

Fatigue is the most debilitating symptom in patients with multiple sclerosis (MS). Natalizumab and rituximab are the most used MS disease modifying therapies in Sweden, but comparative data on the effect on fatigue is sparse.

Objective

Primary objective was to compare fatigue levels between patients on natalizumab and rituximab. As secondary objective, we assessed processing speed, an attention domain quality, between treatment groups.

Method

In this Swedish multicentre cross-sectional study, patients with relapsing-remitting MS and >24 months treatment duration were identified in the Swedish MS-registry. Fatigue was assessed using the Fatigue Scale for Motor and Cognitive functions (FSMC) and processing speed using Symbol Digit Modalities Test (SDMT).

Results

128 patients were enrolled (natalizumab: 56, rituximab: 72). No significant differences in FSMC were found when adjusting for potential confounders (p = 0.936), with age having the biggest impact, correlating with increased fatigue. Individuals on natalizumab performed significantly better on SDMT at cross-section (natalizumab 64.7, rituximab 56.2; p = 0.003), with an improvement from treatment initiation, compared to rituximab (change: natalizumab 8.9, rituximab -1.0; p = 0.002).

Conclusion

We found no difference in fatigue levels between natalizumab and rituximab cohorts. Patients treated with natalizumab showed significantly better results on SDMT than patients on rituximab.

Longitudinal Effects of Elexacaftor/Tezacaftor/Ivacaftor: Multidimensional Assessment of Neuropsychological Side Effects and Physical and Mental Health Outcomes in Adolescents and Adults

BACKGROUND

Italy initiated elexacaftor/tezacaftor/ivacaftor (ETI) for people with cystic fibrosis (pwCF) in July 2021. It has led to dramatic improvements in lung function, BMI, sweat chloride, and respiratory symptoms. However, few data are available on side effects or effects on a broad range of outcomes.

RESEARCH QUESTION

How does ETI affect mental health, cognitive processing, neuropsychological side effects, GI symptoms, and health-related quality of life over time?

STUDY DESIGN AND METHODS

This was a prospective, "real-world" longitudinal study. Participants were recruited consecutively and evaluated at initiation (T0) and after 1 month, 3 months, and 6 months of starting treatment. Assessments included depression (nine-item Patient Health Questionnaire), anxiety (seven-item Generalized Anxiety Disorder), cognition (Symbol Digit Modalities Test), GI Symptom Tracker, and health-related quality of life (Cystic Fibrosis Questionnaire-Revised). Based on literature, an ad hoc questionnaire was developed to assess side effects: insomnia, headache, memory problems, "brain fog," and concentration problems. Following descriptive analyses, longitudinal data were analyzed by using mixed models for repeated measures, controlling for age and sex when appropriate.

RESULTS

Ninety-two consecutive pwCF (female/male, 46/46; mean age, 25.4 years) participated. FEV1 increased initially and then remained stable. BMI also increased significantly from T0 to 6 months (P < .01). Depression improved from T0 to 1 month (P < .001); however, no changes in anxiety were found. Cognitive processing improved from T0 to subsequent assessments. Positive changes were reported on the GI Symptom Tracker for stools and adherence challenges, although no changes were found for abdominal pain and digestion. Side effects occurred in 10% to 29%, with no reduction over time; insomnia increased significantly across time. Female participants reported more side effects than male participants (ie, insomnia, headache, concentration problems, brain fog).

INTERPRETATION

This prospective study evaluated the effects of ETI using multiple measures. Significant improvements were found in many domains; however, side effects were reported by a substantial proportion of pwCF, with no improvements over time. Female participants reported more side effects than male participants. pwCF should be followed up systematically to assess the frequency of side effects after starting this new modulator.

Defining a standard set of health outcomes for patients with relapsing-remitting multiple sclerosis

BACKGROUND

Standardizing health outcomes is challenging in clinical management, but it also holds the potential for creating a healthcare system that is both more effective and efficient. The aim of the present study is to define a standardized set of health outcomes for managing Relapsing-Remitting Multiple Sclerosis (RRMS).

METHODS

The project was led and coordinated by a multidisciplinary scientific committee (SC), which included a literature review, a patient-focused group, three nominal group meetings, and two SC meetings.

RESULTS

36 outcome variables were included in the standard set: 24 clinical (including weight, smoking habit, comorbidities, disability, mobility, diagnosis of secondary progressive multiple sclerosis, relapsed-related variables, radiological variables, cognitive status and disease-related symptoms), nine treatment-related (pharmacological and non-pharmacological information), and 3 related to the impact of RRMS on the patient's life (quality of life, pregnancy desire, work-related difficulties). In addition, experts also agreed to collect 10 case-mix variables that may affect but cannot be controlled as part of the management of the condition: 4 sociodemographic (age, sex, race, and employment status) and 6 clinical (height, date of diagnosis and first episode, serological status, early symptoms, and number of relapses pre-diagnosis).

CONCLUSION

The information provided through the present standard set of outcome variables can improve the management of RRMS and promote patient-centred quality care.

Cognitive phenotypes in multiple sclerosis: mapping the spectrum of impairment

BACKGROUND

Available criteria for cognitive phenotypes in multiple sclerosis (MS) do not consider the severity of impairment.

OBJECTIVES

To identify cognitive phenotypes with varying degrees of impairment in MS patients and describe their demographic, clinical and MRI characteristics.

METHODS

Two hundred and forty-three MS patients and 158 healthy controls underwent neuropsychological tests to assess memory, attention, and executive function. For each domain, mild impairment was defined as performing 1.5 standard deviations below the normative mean on two tests, while the threshold for significant impairment was 2 standard deviations. Patients were classified into cognitive phenotypes based on severity of the impairment (mild/significant) and number of domains affected (one/more).

RESULTS

Five cognitive phenotypes emerged: Preserved cognition (PC; 56%), Mild Single-Domain Impairment (MSD; 15%), Mild Multi-Domain Impairment (MMD; 9%), Significant Single-Domain Impairment (SSD; 12%), Significant Multi-Domain Impairment (SMD; 8%). Compared with PC, MSD patients were older, had longer disease duration (DD) and higher T2-hyperintense lesion volume (LV; all p ≤ 0.02); MMD patients were older, had longer DD, higher disability, higher T2 LV and lower thalamic volume (all p ≤ 0.01); SSD patients had longer DD and lower gray matter cortical volume, thalamic, caudate, putamen and accumbens volumes (all p ≤ 0.04); and SMD patients were older, had longer DD, higher disability and more extensive structural damage in all brain regions explored (all p ≤ 0.03), except white matter and amygdala volumes.

CONCLUSIONS

We identified five cognitive phenotypes with graded levels of impairment. These phenotypes were characterized by distinct demographic, clinical and MRI features, indicating potential variations in the neural substrates of dysfunction throughout disease stages.

Understanding the Symptoms and Impacts Experienced by People with Relapsing-Remitting MS: A Qualitative Investigation Using Semi-Structured Interviews

INTRODUCTION

Multiple sclerosis (MS) is a disabling disease with unpredictable clinical manifestations. As clinical assessments may not fully capture the impact of MS on quality of life, they can be complemented by patient-reported outcome (PRO) measures to provide a more comprehensive picture of MS disease state and impact. The objectives of this study were to explore the experiences of people with relapsing-remitting MS, including symptoms and impacts on daily life, and to provide a conceptual model of MS outcomes.

METHODS

A literature review of studies that evaluated the experiences of people with MS was completed and combined with semi-structured concept elicitation interviews conducted with 14 people with relapsing-remitting MS in the USA.

RESULTS

The average age of the 14 participants was 43.9 (range 25-64) years, most were White (78.6%) and female (78.6%), and the mean duration since diagnosis was 6.6 (2-10) years. The most bothersome symptoms identified included fatigue (n = 9), cognitive dysfunction (n = 5), mobility/difficulty with walking (n = 3), and vision problems (n = 3). The most commonly reported impacts on daily life were balance problems/instability (n = 13), work life/productivity (n = 12), difficulty walking (n = 11), daily activities/household chores (n = 11), and leisure activities (n = 10).

CONCLUSION

There was a high frequency of concepts associated with physical function, fatigue, and sensory-motor actions. A conceptual model was developed that captures the disease symptoms, impairments, and impacts identified in the interviews as well as known processes and symptoms identified in the literature search. This model underpins the appropriateness of PRO instruments, such as the PROMIS Fatigue (MS) 8a and PROMIS Physical Function (MS) 15a, which evaluate symptoms and impacts that matter most to people with MS.

Validation of the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) in individuals with multiple sclerosis from Mexico

BACKGROUND

Cognitive impairment is observed in 43-70 % of Multiple sclerosis (MS) patients. One of the most widely used batteries for cognitive assessment in this population is the Brief International Cognitive Assessment for MS (BICAMS). The objective of this study was to validate and assess the reliability of the BICAMS in a Mexican population with MS and to obtain and provide regression-based norms.

METHODS

One hundred healthy controls (HCs) and 100 patients with multiple sclerosis participated in the present study, and groups were matched for age, years of education and sex. Subjects completed all three tests of the BICAMS. Test-retest measures were obtained from 30 patients to test reliability.

RESULTS

The sample´s average age was 43.39 ± 6.03 years old, and the average years of education was 12.55 ± 2.52 years. Approximately 63 % of the participants were female. The groups did not differ in age, years of education, or sex. The MS group performed significantly worse than the HCs group on all three neuropsychological tests. A significant difference was observed for the SDMT (t = 10.166; p=<0.001), CVLT-II (t = 10.949; p=<0.001), and BVMT-R (t = 2.636; p = 0.009). For all comparisons, the effect size (d) for each test was calculated as follows: SDMT= 0.58 and CVLT-II= 0.61. The test-retest coefficients for each test were as follows: SDMT: r = 0.95; CVLT-II: r = 0.84; and BVMT-R = 0.81.

CONCLUSION

The BICAMS can provide information on cognitive impairment in MS patients, and this information can be used by neuropsychologists for cognitive rehabilitation in different domains.

Proteomic signatures of physical, cognitive, and imaging outcomes in multiple sclerosis

BACKGROUND

A quantitative measurement of serum proteome biomarkers that would associate with disease progression endpoints can provide risk stratification for persons with multiple sclerosis (PwMS) and supplement the clinical decision-making process.

MATERIALS AND METHODS

In total, 202 PwMS were enrolled in a longitudinal study with measurements at two time points with an average follow-up time of 5.4 years. Clinical measures included the Expanded Disability Status Scale, Timed 25-foot Walk, 9-Hole Peg, and Symbol Digit Modalities Tests. Subjects underwent magnetic resonance imaging to determine the volumetric measures of the whole brain, gray matter, deep gray matter, and lateral ventricles. Serum samples were analyzed using a custom immunoassay panel on the Olink™ platform, and concentrations of 18 protein biomarkers were measured. Linear mixed-effects models and adjustment for multiple comparisons were performed.

RESULTS

Subjects had a significant 55.6% increase in chemokine ligand 20 (9.7 pg/mL vs. 15.1 pg/mL, p < 0.001) and neurofilament light polypeptide (10.5 pg/mL vs. 11.5 pg/mL, p = 0.003) at the follow-up time point. Additional changes in CUB domain-containing protein 1, Contactin 2, Glial fibrillary acidic protein, Myelin oligodendrocyte glycoprotein, and Osteopontin were noted but did not survive multiple comparison correction. Worse clinical performance in the 9-HPT was associated with neurofilament light polypeptide (p = 0.001). Increases in several biomarker candidates were correlated with greater neurodegenerative changes as measured by different brain volumes.

CONCLUSION

Multiple proteins, selected from a disease activity test that represent diverse biological pathways, are associated with physical, cognitive, and radiographic outcomes. Future studies should determine the utility of multiple protein assays in routine clinical care.

Retinal clues for selective neuronal loss in multiple sclerosis

OBJECTIVE

The relationship between the cell body layer and the dendritic network layer of the retina and cognitive performance (CP) in MS patients has not been examined separately. The objective of this study is to predict cognitive impairment (CI) in RRMS patients and to examine the relationship between CP and ganglion cell layer (GCL), inner plexiform layer (IPL), and GCL divided by IPL (GCL/IPL).

METHODS

Ophthalmological evaluation, retinal segmentation, and Symbol Digit Modalities Test (SDMT) were performed on 102 RRMS patients and 54 healthy subjects. The relationships of GCL, IPL, and GCL/IPL with CP in eyes without a history of optic neuritis were investigated using Spearman's correlation. Models were created by accepting 1 standard deviation less of the SDMT mean of the control group as the limit for CI. The cutoff value of the GCL/IPL variable that could predict CI was calculated by ROC analysis, and the ability to accurately predict CI was tested with binary logistic regression.

RESULTS

No correlation was found between OCT parameters and CP in healthy subjects. Correlation was found between GCL thickness and GCL/IPL variable and CP in RRMS patients (r=0.235, r=0.667 respectively). A GCL/IPL value of 1.255 was able to identify CI with 81.8% sensitivity and 75.9% specificity (AUC=0.844, LR=3.38) and predicted CI with 74.5% accuracy (Nagelkerke R2=0.439).

CONCLUSION

In RRMS patients, the IPL thickness is unrelated to CP. Therewithal, the GCL/IPL-CP relationship is stronger than the GCL-CP relationship and GCL/IPL can predict CI.

Premorbid cognitive functioning influences differences between self-reported cognitive difficulties and cognitive assessment in multiple sclerosis

Cognitive difficulties are reported in up to 60% of people with MS (pwMS). There is often a discrepancy between self-reported cognitive difficulties and performance on cognitive assessments. Some of this discrepancy can be explained by depression and fatigue. Pre-MS cognitive abilities may be another important variable in explaining differences between self-reported and assessed cognitive abilities. PwMS with high estimated premorbid cognitive functioning (ePCF) may notice cognitive difficulties in daily life whilst performing within the average range on cognitive assessments. We hypothesised that, taking into account depression and fatigue, ePCF would predict (1) differences between self-reported and assessed cognitive abilities and (2) performance on cognitive assessments. We explored whether ePCF predicted (3) self-reported cognitive difficulties. Eighty-seven pwMS completed the Test of Premorbid Functioning (TOPF), the Brief International Cognitive Assessment for MS (BICAMS), self-report measures of cognitive difficulty (MS Neuropsychological Questionnaire; MSNQ), fatigue (MS Fatigue Impact Scale; MFIS) and depression (Hospital Anxiety and Depression Scale; HADS). Results revealed that, taking into account covariates, ePCF predicted (1) differences between self-reported and assessed cognitive abilities, p < .001 (model explained 29.35% of variance), and (2) performance on cognitive assessments, p < .001 (model explained 46.00% of variance), but not (3) self-reported cognitive difficulties, p = .545 (model explained 35.10% of variance). These results provide new and unique insights into predictors of the frequently observed discrepancy between self-reported and assessed cognitive abilities for pwMS. These findings have important implications for clinical practice, including the importance of exploring premorbid factors in self-reported experience of cognitive difficulties.

Domain-specific cognitive impairment in multiple sclerosis: A systematic review and meta-analysis

OBJECTIVE

Methods of cognitive measurements in multiple sclerosis (MS) are not standardized. We aimed to identify the prevalence of cognitive domain-specific impairment (DSI) in MS by using subtests of the Brief Repeatable Battery of Neuropsychological Tests (BRB-N) with analyzing different cutoff values.

METHODS

The systematic review and meta-analysis were registered on PROSPERO (ID: CRD42021287004). The systematic literature search was performed via PubMed, Embase, and CENTRAL on 24 October 2021. Inclusion criteria were adults of different MS subtypes (CIS, RRMS, PPMS, and SPMS) with the condition of distinct DSI measured by BRB-N. Pediatric MS, computerized versions of BRB-N, and patients receiving steroids were excluded. Primary outcome was pooled prevalence rates of impaired patients within each cutoff and MS subtype, with 95% confidence interval, I-squared statistics for heterogeneity, and chi-squared test for subgroup differences. Risk of bias was assessed using the "JBI Quality Assessment Tool for Prevalence Studies."

RESULTS

In 48 eligible observational studies (n = 3431 patients), the three most prevalent thresholds were the 2.0 SD and 1.5 SD below the mean of normative values, and the score below the fifth percentile of the normative values. A progressively increasing worsening of the overall DSI was observed from CIS, moving toward RRMS, PPMS, and SPMS.

INTERPRETATION

Cognitive impairment is observed in all MS phenotypes, with varying degrees. Due to several potential influencing factors, our comprehensive literature review has not revealed consistent findings, and we, therefore, recommend considering a more sophisticated, "individual referencing" approach, acknowledging the diverse clinical and sociodemographic characteristics among populations and disparities in cognitive testing.

Disutility of Cognitive Processing Speed (CPS) Impairment in the Context of Multiple Sclerosis: A Time Trade-Off (TTO) Elicitation Study

Introduction

Cognitive impairment, especially relating to cognitive processing speed, is a major cause of disability in people with multiple sclerosis (MS). Utility values are quantitative estimates of the quality of life experienced in specific health states and are a key component of cost-effectiveness modelling. However, existing health state utility values in MS typically focus on physical ability and are generally derived using generic (not disease-specific) measures of quality of life. The objective of the current study was to generate health state utility values for levels of cognitive impairment. We used a direct utility elicitation approach called the time trade-off (TTO) methodology.

Materials and Methods

Health state descriptions were created following interviews with healthcare professionals, patients, and caregivers in the United States (n=35), and with healthcare professionals in the UK (n=5). Three health states (mild, moderate, and severe impairment) were defined based upon a well-established and validated test for cognitive dysfunction called the Symbol Digit Modalities Test (SDMT) and described using qualitative interview findings. Next, interviews with members of the general public in the UK were conducted to estimate utility values for each health state using the TTO methodology. The procedure was based on the established Measurement and Valuation of Health (MVH) protocol, which generates values on a scale from 0.0 to 1.0.

Results

Mean health state utility values were 0.77 ± 0.24 in "mild impairment" (SDMT 43-40), 0.57 ± 0.26 in "moderate impairment" (SDMT 39-32), and 0.34 ± 0.28 in "severe impairment" (SDMT ≤ 31).

Discussion

Results indicate that the public perceives that health states of cognitive slowing (as observed in MS) are associated with a substantial reduction in affected individuals' health-related quality of life, quantified using the TTO methodology. Future economic modeling should consider how utility impacts of both cognitive and physical disability can be appropriately incorporated.

Clinical features of sleep apnea syndrome and cognitive impairment in multiple sclerosis

BACKGROUND

Complications of obstructive sleep apnea (OSA) have been reported in patients with multiple sclerosis (MS). Patients with sleep apnea syndrome (SAS) due to OSA also show cognitive decline, with similar clinical characteristics to that manifested in MS. SAS due to OSA is a treatable condition, and the associated cognitive decline is expected to improve. This study investigates clinical features of SAS in people living with MS and contribute to improve cognitive dysfunction of MS.

METHODS

A case-control study was conducted. Cognitive functions were evaluated by the Symbol Digit Modalities Test (SDMT) and the Paced Auditory Serial Addition Test 2 (PASAT-2) and 3 (PASAT-3). The Respiratory Event Index (REI) was measured using Out of Center Sleep Testing (OCST). We defined subjects with REI ≥ 5 as OSA and divided participants into two groups with or without SAS due to OSA. Cognitive and respiratory characteristics were statistically compared between patients with MS and healthy controls.

RESULTS

We enrolled 67 people living with MS and 31 age- and sex-matched controls. OCST detected OSA in people living with MS and controls, and the prevalence rates were 28.4 % and 25.8 %, respectively. REI values (5.2 ± 7.9 vs 3.9 ± 5.2, p = 0.509) and number of participants with REI ≥ 5 (19 vs 8, p = 0.793) were similar between the MS and control group. The SDMT, PASAT-2, and PASAT-3 scores were significantly lower in the MS group than the control group (p < 0.001, p = 0.001, and p < 0.001, respectively). The interaction effect of MS and SAS on cognitive function was not significant in the SDMT (p = 0.078), but in the PASAT-2 (p = 0.043) and PASAT-3 (p = 0.020).

CONCLUSION

This study revealed the prevalence rates of SAS in Japanese people living with MS and the usefulness of OCST for detection of SAS. This study also revealed that concomitant SAS can facilitate cognitive decline in people living with MS. These findings suggest that an appropriate intervention for OSA can be beneficial for people living with MS with cognitive decline.

Pathophysiology, Diagnosis, Treatment and Emerging Neurotherapeutic Targets for Progressive Multiple Sclerosis: The Age of PIRA

More than one million individuals are impacted by progressive forms of multiple sclerosis. The literature examining the management of MS has focused primarily on relapsing forms of disease, and effective therapies targeting progressive mechanisms in MS remains a significant unmet need. Despite this, there are several encouraging potential therapeutics on the horizon. Improved understanding of mechanisms underlying MS progression, identification and validation of biomarkers, identification of novel therapeutic targets, and improved trial design are needed to further propel progress in the management of individuals with progressive forms of MS.

Multiple sclerosis

Multiple sclerosis remains one of the most common causes of neurological disability in the young adult population (aged 18-40 years). Novel pathophysiological findings underline the importance of the interaction between genetics and environment. Improvements in diagnostic criteria, harmonised guidelines for MRI, and globalised treatment recommendations have led to more accurate diagnosis and an earlier start of effective immunomodulatory treatment than previously. Understanding and capturing the long prodromal multiple sclerosis period would further improve diagnostic abilities and thus treatment initiation, eventually improving long-term disease outcomes. The large portfolio of currently available medications paved the way for personalised therapeutic strategies that will balance safety and effectiveness. Incorporation of cognitive interventions, lifestyle recommendations, and management of non-neurological comorbidities could further improve quality of life and outcomes. Future challenges include the development of medications that successfully target the neurodegenerative aspect of the disease and creation of sensitive imaging and fluid biomarkers that can effectively predict and monitor disease changes.

Immunomodulators and immunosuppressants for relapsing-remitting multiple sclerosis: a network meta-analysis

BACKGROUND

Different therapeutic strategies are available for the treatment of people with relapsing-remitting multiple sclerosis (RRMS), including immunomodulators, immunosuppressants and biological agents. Although each one of these therapies reduces relapse frequency and slows disability accumulation compared to no treatment, their relative benefit remains unclear. This is an update of a Cochrane review published in 2015.

OBJECTIVES

To compare the efficacy and safety, through network meta-analysis, of interferon beta-1b, interferon beta-1a, glatiramer acetate, natalizumab, mitoxantrone, fingolimod, teriflunomide, dimethyl fumarate, alemtuzumab, pegylated interferon beta-1a, daclizumab, laquinimod, azathioprine, immunoglobulins, cladribine, cyclophosphamide, diroximel fumarate, fludarabine, interferon beta 1-a and beta 1-b, leflunomide, methotrexate, minocycline, mycophenolate mofetil, ofatumumab, ozanimod, ponesimod, rituximab, siponimod and steroids for the treatment of people with RRMS.

SEARCH METHODS

CENTRAL, MEDLINE, Embase, and two trials registers were searched on 21 September 2021 together with reference checking, citation searching and contact with study authors to identify additional studies. A top-up search was conducted on 8 August 2022.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that studied one or more of the available immunomodulators and immunosuppressants as monotherapy in comparison to placebo or to another active agent, in adults with RRMS.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies and extracted data. We considered both direct and indirect evidence and performed data synthesis by pairwise and network meta-analysis. Certainty of the evidence was assessed by the GRADE approach.

MAIN RESULTS

We included 50 studies involving 36,541 participants (68.6% female and 31.4% male). Median treatment duration was 24 months, and 25 (50%) studies were placebo-controlled. Considering the risk of bias, the most frequent concern was related to the role of the sponsor in the authorship of the study report or in data management and analysis, for which we judged 68% of the studies were at high risk of other bias. The other frequent concerns were performance bias (34% judged as having high risk) and attrition bias (32% judged as having high risk). Placebo was used as the common comparator for network analysis. Relapses over 12 months: data were provided in 18 studies (9310 participants). Natalizumab results in a large reduction of people with relapses at 12 months (RR 0.52, 95% CI 0.43 to 0.63; high-certainty evidence). Fingolimod (RR 0.48, 95% CI 0.39 to 0.57; moderate-certainty evidence), daclizumab (RR 0.55, 95% CI 0.42 to 0.73; moderate-certainty evidence), and immunoglobulins (RR 0.60, 95% CI 0.47 to 0.79; moderate-certainty evidence) probably result in a large reduction of people with relapses at 12 months. Relapses over 24 months: data were reported in 28 studies (19,869 participants). Cladribine (RR 0.53, 95% CI 0.44 to 0.64; high-certainty evidence), alemtuzumab (RR 0.57, 95% CI 0.47 to 0.68; high-certainty evidence) and natalizumab (RR 0.56, 95% CI 0.48 to 0.65; high-certainty evidence) result in a large decrease of people with relapses at 24 months. Fingolimod (RR 0.54, 95% CI 0.48 to 0.60; moderate-certainty evidence), dimethyl fumarate (RR 0.62, 95% CI 0.55 to 0.70; moderate-certainty evidence), and ponesimod (RR 0.58, 95% CI 0.48 to 0.70; moderate-certainty evidence) probably result in a large decrease of people with relapses at 24 months. Glatiramer acetate (RR 0.84, 95%, CI 0.76 to 0.93; moderate-certainty evidence) and interferon beta-1a (Avonex, Rebif) (RR 0.84, 95% CI 0.78 to 0.91; moderate-certainty evidence) probably moderately decrease people with relapses at 24 months. Relapses over 36 months findings were available from five studies (3087 participants). None of the treatments assessed showed moderate- or high-certainty evidence compared to placebo. Disability worsening over 24 months was assessed in 31 studies (24,303 participants). Natalizumab probably results in a large reduction of disability worsening (RR 0.59, 95% CI 0.46 to 0.75; moderate-certainty evidence) at 24 months. Disability worsening over 36 months was assessed in three studies (2684 participants) but none of the studies used placebo as the comparator. Treatment discontinuation due to adverse events data were available from 43 studies (35,410 participants). Alemtuzumab probably results in a slight reduction of treatment discontinuation due to adverse events (OR 0.39, 95% CI 0.19 to 0.79; moderate-certainty evidence). Daclizumab (OR 2.55, 95% CI 1.40 to 4.63; moderate-certainty evidence), fingolimod (OR 1.84, 95% CI 1.31 to 2.57; moderate-certainty evidence), teriflunomide (OR 1.82, 95% CI 1.19 to 2.79; moderate-certainty evidence), interferon beta-1a (OR 1.48, 95% CI 0.99 to 2.20; moderate-certainty evidence), laquinimod (OR 1.49, 95 % CI 1.00 to 2.15; moderate-certainty evidence), natalizumab (OR 1.57, 95% CI 0.81 to 3.05), and glatiramer acetate (OR 1.48, 95% CI 1.01 to 2.14; moderate-certainty evidence) probably result in a slight increase in the number of people who discontinue treatment due to adverse events. Serious adverse events (SAEs) were reported in 35 studies (33,998 participants). There was probably a trivial reduction in SAEs amongst people with RRMS treated with interferon beta-1b as compared to placebo (OR 0.92, 95% CI 0.55 to 1.54; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

We are highly confident that, compared to placebo, two-year treatment with natalizumab, cladribine, or alemtuzumab decreases relapses more than with other DMTs. We are moderately confident that a two-year treatment with natalizumab may slow disability progression. Compared to those on placebo, people with RRMS treated with most of the assessed DMTs showed a higher frequency of treatment discontinuation due to AEs: we are moderately confident that this could happen with fingolimod, teriflunomide, interferon beta-1a, laquinimod, natalizumab and daclizumab, while our certainty with other DMTs is lower. We are also moderately certain that treatment with alemtuzumab is associated with fewer discontinuations due to adverse events than placebo, and moderately certain that interferon beta-1b probably results in a slight reduction in people who experience serious adverse events, but our certainty with regard to other DMTs is lower. Insufficient evidence is available to evaluate the efficacy and safety of DMTs in a longer term than two years, and this is a relevant issue for a chronic condition like MS that develops over decades. More than half of the included studies were sponsored by pharmaceutical companies and this may have influenced their results. Further studies should focus on direct comparison between active agents, with follow-up of at least three years, and assess other patient-relevant outcomes, such as quality of life and cognitive status, with particular focus on the impact of sex/gender on treatment effects.

Frequency of cognitive impairment in patients with neuromyelitis optica spectrum disorder in Mexico

Background

Between 29% and 67% of neuromyelitis optica spectrum disorder patients have cognitive alterations.

Objective

To assess the frequency of cognitive impairment in patients with neuromyelitis optica spectrum disorder in Mexico using the Brief International Cognitive Assessment for Multiple Sclerosis.

Methods

We evaluated 40 neuromyelitis optica spectrum disorder patients and 40 healthy controls from Mexico.

Results

28 (70.0%) patients with neuromyelitis optica spectrum disorder had cognitive impairment in two or more cognitive domains. Student´s T test showed statistically poor performance by neuromyelitis optica spectrum disorder patients compared to healthy controls on all three neuropsychological test scores. This significant difference was observed on the Symbols Digit Modalities Test (t = 8.875; p ≤ 0.001); California Verbal Learning Test-II memory (t = 10.418; p ≤ 0.001); and Brief Visuospatial Memory Test Revised (t = 6.123; p ≤ 0.001).

Conclusions

This study showed that 70% of neuromyelitis optica spectrum disorder patients exhibited cognitive impairment in two or more cognitive domains. Determining the frequency of cognitive impairment will guide the decision of Neuropsychologists in planning cognitive rehabilitation across various domains.