Disease modifying treatments and symptomatic drugs for cognitive impairment in multiple sclerosis: where do we stand?

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.

Cognitive impairment and its impact on employment: A qualitative interview-based study involving healthcare professionals and people living with multiple sclerosis

BACKGROUND

Cognitive impairment can considerably impact the work life of people who have multiple sclerosis (MS). Cognitive symptoms are associated with an increased likelihood of unemployment, changes in employment and decreased working hours. This qualitative interview-based study aims to gather real-word experiences and perspectives from both people living with MS and healthcare professionals, to explore how cognitive symptoms are experienced in the workplace, how their impact is addressed, and what can be done to support people in managing and minimizing this impact on employment.

METHODS

Semi-structured, one-to-one interviews were conducted with people living with MS who experience cognitive symptoms, and with healthcare professionals working in MS care. Participants were recruited from a healthcare market research agency based in the United States. The data obtained from the interviews were subsequently analysed using a Grounded Theory method, in order to identify the core themes that form the basis of this paper.

RESULTS

A total of 20 participants (n = 10 people living with MS; n = 10 healthcare professionals) from the United States were interviewed. Overall, 9 themes were identified from the raw data, which were grouped into three core themes describing the perspectives and experiences reported by both people living with MS and healthcare professionals: (1) The implications of cognitive symptoms on work; (2) Challenges in addressing cognitive impairment and its impact on work in MS care; (3) Strategies and support for managing the impact of cognitive symptoms.

CONCLUSION

The real-world insights of PwMS and HCPs gained from this qualitative study show that a multi-faceted approach to addressing cognitive impairment and its impact on the employment of PwMS is required. Workplace adjustments can range from self-implemented changes to changes put in place by employers to accommodate the various ways in which cognitive symptoms may impact a person's work. This study provides valuable information on how people living with MS can be affected by cognitive symptoms in the context of their employment; furthermore, that preparing early when possible and maintaining a proactive approach to managing their impacts on work are important for maintaining a good quality of life.

Strengthening Mental Abilities with Relational Training (SMART) in multiple sclerosis (MS): study protocol for a feasibility randomised controlled trial

Background

Multiple sclerosis (MS) is a chronic condition of the central nervous system, affecting around 1 in every 600 people in the UK, with 130 new diagnoses every week. Cognitive difficulties are common amongst people with MS, with up to 70% experiencing deficits in higher-level brain functions—such as planning and problem-solving, attention, and memory. Cognitive deficits make it difficult for people with MS to complete everyday tasks and limit their abilities to work, socialise, and live independently. There is a clear need—and recognised research priority—for treatments that can improve cognitive functioning in people with MS. The absence of effective cognitive interventions exacerbates burdens on the services accessed by people with MS—requiring these services to manage sequelae of untreated cognitive deficits, including reduced quality of life, greater disability and dependence, and poorer adherence to disease-modifying treatments. Our planned research will fill the evidence gap through developing—and examining the feasibility of trialling—a novel online cognitive rehabilitation programme for people with MS (SMART). The SMART programme directly trains relational skills (the ability to flexibly relate concepts to one another) based on theory that these skills are critical to broader cognitive functioning.

Methods

The primary objective of this study aims to conduct a feasibility study to inform the development of a definitive trial of SMART for improving cognitive functioning in people with MS. The secondary objective is to develop the framework for a cost-effectiveness analysis alongside a definitive trial, and the exploratory objective is to assess the signal of efficacy.

Discussion

As a feasibility trial, outcomes are unlikely to immediately effect changes to NHS practice. However, this is a necessary step towards developing a definitive trial—and will give us a signal of efficacy, a prerequisite for progression to a definitive trial. If found to be clinically and cost-effective, the latter trial could create a step-change in MS cognitive rehabilitation—improving service delivery and optimising support with limited additional resources.

Trial registration

Registration ID: ClnicalTrials.gov: NCT04975685—registered on July 23rd, 2021.

Protocol version: 2.0, 25 November 2021

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-022-01152-7.

Screening of Cognitive Impairment in Patients with Multiple Sclerosis: A Cross-Sectional Study in Georgia

Cognitive impairment (CI) is a common symptom of multiple sclerosis (MS), with a significant negative impact on the occupational and social functioning of patients. This study aimed to estimate the prevalence and characteristics of CI among MS patients in Georgia. Sixty-eight patients with MS attending a neurology outpatient clinic in Tbilisi, Georgia, were enrolled in the study. Cognitive status was evaluated using two screening tools: the Brief International Cognitive Assessment for MS and the Montreal Cognitive Assessment. The overall prevalence of CI in our MS patients was 47%. We found negative associations between cognitive test results and patients' age, disability status, and depression. Lower education, higher scores on the Expanded Disability Status Scale, and the progressive course of MS were the main predictors of CI in the logistic regression analysis. This is the first study in Georgia to evaluate CI in patients with MS. The prevalence of CI in our study was comparable with those reported in other countries; however, we found greater impairment of the executive system compared to other cognitive domains. In our study, patients who were on continuous DMT showed significantly better performance on the cognitive tests used, indicating possible favorable effect of immunomodulatory drugs on cognition.

Montreal cognitive assessment for evaluating cognitive impairment in multiple sclerosis: a systematic review

This study aims to systematically review the evidence on the accuracy of the Montreal Cognitive Assessment (MoCA) test for evaluating the presence of cognitive impairment in patients with multiple sclerosis (MS) and to outline the quality and quantity of research evidence available about the use of MoCA in this population. We conducted a systematic literature review, searching five databases from inception until May 2020. We identified fourteen studies that met the inclusion criteria: three cross-sectional studies and two case - control studies comparing MoCA to a battery of tests, one study comparing MoCA to Mini-Mental State Examination (MMSE), and eight studies estimating the prevalence of cognitive impairment in individuals with MS. Publication period ranged from 2012 to 2020. Although the MoCA test demonstrated good sensitivity and specificity when used at the recommended threshold of 26, a lower threshold than the original cut-off was also reported to be useful for optimal screening, as it lowers false positive rates and improves diagnostic accuracy. Furthermore, in MS patients without subjective cognitive complaints, a cutoff of 27 could provide a better balance between the sensitivity and the specificity of the test. In patients with MS, the MoCA provides information on general cognitive functions disturbances. Nonetheless, more studies are required to examine the optimum cut-off score for detecting cognitive impairments in MS patients.

Clinically reliable cognitive decline in relapsing remitting multiple sclerosis: Is it the tip of the iceberg?

OBJECTIVES

Cognitive impairment is common in multiple sclerosis, but the brain MRI correlates in relapsing remitting multiple sclerosis remain controversial. The current study aimed to investigate whether cognitive decline can be predicted by global and/or regional brain atrophy.

METHODS

Sixty-three patients with relapsing remitting multiple sclerosis (36 men, mean age 39.9 ± 9.4 years old, mean EDSS 1.4 ± 1.2, mean disease duration 4.9 ± 4.3 years) and 46 healthy controls (21 men, mean age 37.5 ± 10.8 years old) were included. Demographic data were obtained, and a longitudinal neuropsychological and global and regional MRI brain volume assessment was performed.

RESULTS

The patients performed worse than controls in most neuropsychological tests at baseline. The percentage of patients with clinically meaningful cognitive decline ranged from only 0% to 7.9%. Statistically significant volume reduction was found for all MRI measures except for the left accumbens nucleus. Whole or regional brain atrophy ranged from -0.02% to -0.25%, with subcortical structures showing the largest atrophy rates. A total of 22.2% to 93.7% patients showed atrophy across the brain structures assessed volumetrically.

DISCUSSION

It was regional rather than whole-brain changes that significantly predicted cognitive decline for the patients in the tasks that tested processing speed, visuo-spatial and inhibition skills. The overall data suggest that the progression of cognitive impairment in relapsing remitting multiple sclerosis as captured by conventional neuropsychological testing is the tip of the iceberg of neurodegenerative sequelae in the disease. Also, regional volumetric changes are better than whole-brain atrophy at predicting cognitive dysfunction.

Patient Attitudes to Routine Cognitive Testing in Multiple Sclerosis

BACKGROUND AND AIM

In recent years, cognitive dysfunction (CD) in multiple sclerosis (MS) has received increased attention. Neuropsychological tests have been developed allowing to monitor changes in patients' cognitive functions. Knowledge is lacking, however, about patients' attitudes towards introducing routine cognitive testing. It was the aim of this qualitative study to explore this.

MATERIALS AND METHODS

Based on a literature study, semi-structured interview guides were designed and used in qualitative interviews with 12 Danish patients. Participants were selected to represent different perspectives on CD and included patients with relapsing-remitting MS (RRMS) and secondary-progressive MS (SPMS), women and men with varying time since diagnosis and cognitive test scores using the Symbol Digit Modalities Test (SDMT). The data were analysed using a constructivist approach in order to identify significant relations between the quality of life (QoL) impact of CD, and attitudes towards routine cognitive testing.

RESULTS

Most participants reported several subtypes of CD, yet objective CD did not coincide with subjective CD nor did it translate directly into poorer QoL. Overall, CD appeared to have larger impact on the QoL of patients with RRMS and higher SDMT scores, compared to patients with SPMS and lower SDMT scores. The QoL impact of CD manifested itself in the encounter between individual symptoms, expectations, coping and meaningful activities. All patients supported an introduction of routine cognitive testing, but patients with RRMS and SPMS had different main reasons to do so. These were related to supporting research, optimising treatment decisions, and providing documentation of this invisible MS symptom.

CONCLUSION

All aspects of MS patients' QoL may be affected by CD. Introducing routine cognitive testing was widely supported by patients in all phases of MS calling for comprehensive care taking both physical and cognitive difficulties into account.

A Pilot Study to Assess At-Home Speed of Processing Training for Individuals with Multiple Sclerosis

Objective

Cognitive impairment is a common symptom of multiple sclerosis (MS), yet treatment is currently limited. The primary goal of this pilot study was to assess the feasibility and acceptability of an at-home, five-week computerized speed of processing (SOP) training intervention for MS patients. In addition, we examined the utility of the intervention to improve speed of information processing, memory, executive function, and health-related quality of life (HRQOL).

Method

Fifteen subjects were assigned five weeks of SOP training, two times per week, for a total of ten sessions. Subjects were trained on five computerized SOP tasks that required processing of increasingly complex visual stimuli in successively shorter presentation times. Subjects were given a neuropsychological test battery that included measures of speed of information processing, verbal memory, visual spatial memory, and executive function. Subjects were also administered patient-reported outcome (PRO) measures to assess HRQOL, depression, and work productivity. Neuropsychological and PRO batteries were completed at baseline and after five weeks.

Results

Eighty percent of subjects completed the five-week intervention (n = 12). Significant improvements were observed on some, but not all, measures of speed of information processing, verbal memory, and executive function. There were no significant changes in HRQOL.

Conclusion

This pilot study supports the feasibility of an at-home SOP training intervention for individuals with MS. SOP training was associated with improvements in several cognitive domains. Larger, randomized controlled trials are warranted.