FormalPara Key Summary Points

Cognitive impairment is a common manifestation in multiple sclerosis (MS) and can have a considerable impact on the quality of life of people living with MS: however, it is not embedded into the MS care approach in the way that physical impairment is, resulting in it being overlooked for many people with MS

A panel of three experts from the Multiple Sclerosis in the 21st Century group discussed this aspect of MS and elucidated that the low prioritisation of cognitive impairment in MS care can be attributed to several factors, including the ‘invisible’ nature of cognitive symptoms, the stigma attached to them and the fact that neurologists are not always trained to consider cognitive impairment outside the context of dementia

Cognitive symptoms can negatively impact the employment, social life and relationships of people living with MS and their participation in shared decision-making in their own care. It is therefore very important for people with MS and their care team to be aware that cognitive impairment can affect their daily life, and that there is support available to help proactively manage these effects and to maintain cognition in the long term

The panel emphasised the importance of routine cognition assessments in the clinic as well as the need to inform people with MS about the benefits of a brain-healthy lifestyle, building cognitive reserve and the benefits of cognitive rehabilitation programmes for the long-term protection of their cognition

The panel suggested that educational resources about cognitive symptoms and strategies to manage these symptoms would help support healthcare professionals and people with MS and help them be better informed and confident in coping with these symptoms


Multiple sclerosis (MS) is a chronic, neurodegenerative inflammatory disease [1] with a heterogeneous and unpredictable disease course [2, 3]. The disease can result in both physical and cognitive impairment, with the prevalence of the latter ranging from 40 to 70% across different populations of people living with MS (PwMS) [4,5,6]. Furthermore, cognitive impairment manifests across different subtypes of MS and can affect PwMS during both early onset and later stages of the disease [7, 8]. Despite the prevalence of cognitive impairment, clinical care and research have been skewed toward focusing on the physical symptoms and viewing disease progression in terms of physical disability [9]. For example, the Expanded Disability Status Scale (EDSS), [10], which is the gold standard for measuring the extent of disability and changes in disability over time in MS, is heavily skewed toward measuring physical disability [11]. The EDSS does not adequately capture accumulated cognitive impairment or changes in cognition over time [11], nor does it include neuropsychological evaluation [12] or measures of fatigue and depression, which may affect cognition [11].

MS in the 21st Century (MS21) is an international steering committee composed of MS specialists and patient experts dedicated to voicing the experiences and priorities of PwMS and improving communication and shared treatment decision-making in MS care. In a series of open-forum workshops held by the MS21 initiative in 2018, it was highlighted that ‘invisible’ symptoms, including cognitive impairment, were ranked as one of the greatest unmet needs by PwMS. In these workshops, PwMS participants called for more open discussions between themselves and their healthcare professionals (HCPs) regarding these ‘invisible’ symptoms [13]. This suggests that cognitive impairment is not only a significant issue for many PwMS but may also be an aspect of the disease that is under-prioritised in MS care. Open communication is crucial for PwMS to feel heard and for HCPs to respond effectively. MS21 hypothesises that failure to acknowledge the priorities of PwMS has an impact on their willingness to engage with care.

Considering that cognitive impairment in MS is often a key invisible and, therefore, likely unmet need [13], MS21 held a virtual symposium at an ECF meeting on 19 November 2020 to discuss its significant burden on PwMS. The panel consisted of patient expert Dr. Paola Kruger, who is a member of the MS21 steering group, together with two leading clinicians specialising in MS, Prof. Dawn Langdon, who is a neuropsychologist, and Dr. Sarah A. Morrow, an MS neurologist. The discussions and opinions presented in the symposium form the basis of this article, and supporting literature for these perspectives is included. The present commentary did not involve the use of identifiable patient data; therefore, ethical approval and informed consent were not required.

Cognitive Impairment is a Significant, Yet Under-Reported, Aspect of MS

As a neurologist herself, one of the panellists highlighted her perspective that neurologists are generally trained to assess cognitive impairment in the context of dementia and not MS. As a result, they may be considering the disease progression of their patients with MS only in terms of physical disability.

The most widely used tool for assessing disease progression is the EDSS [10], yet this tool is mostly restricted to mobility and lacks adequate measures for capturing cognitive impairment [11, 12]. Furthermore, despite recommendations [14], both early baseline cognition screening and routine monitoring are not always incorporated as part of the treatment plan. This limits the possibility of assessing changes in cognition over time.

As highlighted by the panel, cognition can be considered ‘invisible’ and may not be noticed as easily as physical symptoms, which has been previously acknowledged in MS literature [13, 15]. As a result of this, PwMS may not be aware that certain limitations that they experience in day-to-day life may be attributable to MS-related cognitive symptoms. The panel described how coping mechanisms (e.g., memory notes, phone reminders, use of calendars) help PwMS compensate for these symptoms to some extent, but they may inadvertently mask cognitive impairment. If PwMS themselves are not aware that the cognitive difficulties they are noticing are related to their MS, these symptoms will not be reported to their HCPs.

This problem is especially apparent in elderly PwMS. As the panellists pointed out, advances in MS therapy have resulted in increased life expectancy and, therefore, increased mean age of PwMS [16, 17]. Furthermore, elderly PwMS may also experience signs of cognitive impairment because of age or age-related comorbidities and generally have worse cognitive symptoms than middle-aged PwMS with cognitive impairment [18]. This makes cognitive impairment in elderly PwMS an under-researched and increasingly important topic to explore.

A third point highlighted by the panel was the stigma which can be attached to cognitive impairment. As expressed by one of the panellists, ‘No one goes to see their HCP saying: “I feel stupid, I can’t do my job anymore.”’ The nature of cognitive symptoms is highly sensitive and fear of being judged and shamed discourages open communication between PwMS and their HCPs, which contributes to the under-reporting of such symptoms.

The ‘Everyday’ Matters: The Impact of Cognitive Impairment on PwMS’s Daily Lives

During the symposium, the panel drew attention to the fact that cognitive symptoms in MS can be challenging to manage and often have a profound effect on daily living [9, 19, 20]. The panel stressed that it is important to acknowledge the experiences of PwMS who have cognitive impairment from a practical, day-to-day viewpoint. In the recent past, much focus has been skewed toward the neurological basis of the disease, but less attention has been given to the realities of living with it. In order for clinical care and research to work toward addressing the care priorities of patients, it is crucial to understand what matters to PwMS. Advocating for higher prioritisation of cognition, the panellists discussed several key areas in the lives of PwMS that are considerably affected by these symptoms, which are reported below.

Social Life and Relationships

Social cognition is the mental process which drives interpersonal skills such as social perception, empathy and ‘theory of mind’, which refers to extrapolating others’ states of mind by analysing their facial expression, other behavioural signs and social context [21,22,23]. Acknowledged as a crucial aspect of daily quality of life (QoL) and implicated in several psychological processes, social cognition is one of the deficits manifested as part of cognitive impairment in MS and impacts the QoL and social functioning of PwMS [23,24,25,26,27,28]. Results from a study show an association between social cognition deficits and reduced social and psychological QoL, regardless of disease duration or severity, age or formal neurocognitive test performance [29].

The impacts of these symptoms are experienced on a daily level by affected PwMS, who report difficulties in their relationships, family life and social situations [30, 31]. The patient expert panellist emphasised that, in her opinion, there is an unmet educational need regarding cognitive impairment and its impacts on day-to-day social activities and relationships. According to the panel, the significant burden of cognitive impairment on social life needs to be openly discussed among PwMS, their caregivers/partners, families and their HCPs to understand the implications, navigate the difficulties and adopt helpful coping strategies, where possible, to minimise the effects on social relationships.


Another main point of discussion during the symposium was the impact of cognitive impairment on the employment of PwMS. Cognitive changes that PwMS commonly experience include a decline in cognitive processing speed, memory difficulties, verbal fluency and even difficulties in multitasking (investigated using the ‘dual task paradigm’) [32,33,34]. Therefore, it is perhaps unsurprising that cognitive impairment is significantly associated with unemployment, difficulties in the workplace and reduced work hours [35,36,37]. Research has found that the slower information processing speed experienced by PwMS is a significant predictor of unemployment and decreased working hours [35, 36]. Furthermore, PwMS’s perceived cognitive impairment has been shown to predict poor work outcomes, regardless of their objective performance on cognitive assessments [38]. However, while the panellists noted that this important topic has been acknowledged in the MS literature, they perceived it to remain mostly unaddressed and undiscussed in MS care. The patient expert panellist drew attention to her experiences working with PwMS who were having difficulties in their work life related to their cognitive symptoms, describing how many of these people had little or no guidance from their MS care team on how to cope with this significant impact.

The panel also pointed out that changes in cognition occur over time, and the impact on employment status may often become more apparent years after diagnosis, as supported by the literature [39, 40]. This adds to the challenge of recognising the impact of cognitive impairment and implementing strategies to reduce the risks of future negative employment outcomes that may result. Furthermore, it highlights the value of discussing this aspect of MS with PwMS early on in their MS journey, so that they can be better prepared for their employment future.

During the discussions, the panellists drew attention to the challenge of recognising cognitive impairment as a disability in the workplace: the invisible nature of cognitive symptoms creates a difficult scenario for the employed PwMS experiencing them and for their employers alike. Evidence suggests that PwMS are often faced with the difficulty of deciding whether to disclose their symptoms, since any stigma occurring in the workplace may conflict with their health concerns and personal needs [15]. The panel suggested that employers therefore could benefit from receiving guidance to understand cognitive impairment in MS and facilitate discussions concerning its impact on an employee’s ability to work. With open communication, employers and PwMS who experience and choose to disclose their cognitive symptoms may come to an agreement about working arrangements that accommodate the employee’s changing needs and abilities.

The panel also stressed that the implications of cognitive symptoms on employment, including the possibility of future employment difficulties, should be acknowledged and proactively discussed during consultations with HCPs. HCPs may address employment concerns by providing a referral to a vocational counsellor [15] or vocational rehabilitation programme (a programme aimed at supporting people with a health condition to find work or remain in employment) [41].

Cognitive Impairment and Shared Decision-Making

Shared decision-making between HCPs and patients, especially regarding decisions on treatment selection, is an important facet of patient-centred healthcare (which aims to work toward meeting both HCP and PwMS care priorities) and should be a key tenet for making treatment decisions and optimising treatment satisfaction [42]. Shared decision-making requires the person with MS to understand their treatment options and the ways in which they can proactively participate in self-management. However, the complicating factor for PwMS who have cognitive impairment is that they can experience difficulties with information processing and social cognition, which could impact HCP–PwMS communication and, in turn, the capacity for PwMS to effectively participate and be an active agent in their own MS care [27, 42].

Decision aids, which are education resources designed to facilitate patients’ participation in shared decision-making, have been shown to improve patient knowledge and to help develop accurate risk perceptions [43, 44]. When kept up to date and relevant, these can be valuable tools for helping PwMS with cognitive impairment understand the implications of treatment decisions [44].

The panellists concluded the discussion of this topic by stating that it is crucial for HCPs, PwMS and their caregivers to openly discuss cognitive symptoms and be aware of how these may affect the shared decision-making process. In this manner, they can seek out helpful resources [45], develop strategies to navigate difficulties in communication and aim to maintain a patient-centred care strategy.

The Importance of Routine Cognition Screening and Early Access to Patient Education

Cognition screening around the time of diagnosis, with annual follow-up screening (including further assessment in the case of positive screening results), is recommended for the clinical management of MS [14]. It is the opinion of the panel, based on their experience, that despite these recommendations cognition screening has not been routinely incorporated as part of the MS disease management strategy in many clinics.

There is a current PwMS-driven demand for early access to cognition screening and information about cognitive symptoms. Reporting on discussions held at recent meeting of a stakeholder panel comprising an MS nurse, a person with MS, caregiver, neuropsychologist and two neurologists, the panel relayed the observation that PwMS now are asking for information about cognition from the beginning of their disease journey, and it is often a primary concern at diagnosis [41]. Supporting these observations are findings from a recent qualitative study which, despite its limited sample size (N = 12), revealed insights about patient attitudes toward routine cognition screening. In this study, all participating PwMS supported the practice of routine cognition screening in clinics; furthermore, PwMS felt that documentation of their cognitive symptoms would help facilitate their communication about cognitive impairment with people in their social circle [46].

Given the growing consensus among HCPs and PwMS on the importance of early and subsequent routine assessment of cognition [14], the panel hoped that cognition will become an automatic and integral aspect of all MS care.

The ‘Brain-Healthy’ Lifestyle, Cognitive Reserve and Cognitive Rehabilitation Programmes

The damage to cognitive function in MS is unlikely to be significantly reversible, which the panel highlighted as being the reason why early education about the management of cognition and early initiation of cognition interventions are particularly important. The panel were of the opinion that HCPs may be reluctant to discuss the management of cognition with their patients who have MS, as there are currently limited treatment options and no cure. For this reason, it is possible that many HCPs feel somewhat disempowered to help their patients with MS with these symptoms. However, previous research points to the beneficial effect of having a ‘brain-healthy’ lifestyle involving activities such as mental healthcare, stress reduction practices, social activity, engaging in physical exercise and a healthy diet [47,48,49,50]. The panellists highlighted how a ‘brain-healthy’ lifestyle may not only help to maintain cognition, but also encourage PwMS to be proactive, reminding them of the agency they have in their own MS care. It was agreed among the panel that adhering to a ‘brain-healthy’ lifestyle should therefore be actively discussed and encouraged in MS clinics.

Building cognitive reserve is another way of protecting cognitive function and improving cognitive performance [51,52,53]. Cognitive reserve refers to the resilience against effects of structural brain damage, and the ability of the brain to compensate for injury by shifting functions from damaged areas to non-damaged areas through the neuronal network [54] as a result of accumulated and varied ‘use’ of the brain (past engagement in leisure activities, physical activity and intellectual enrichment) [55, 56]. This theory rests on the idea that accumulated brain use over time leads to greater capacity and efficiency of neuronal networks [57, 58], which implies that early intervention in PwMS by engaging in cognitive reserve-building practices or cognitive rehabilitation programmes would help to prevent future cognitive decline. Encouragingly, there is evidence showing that cognitive rehabilitation programmes can also benefit overall health-related QoL [53, 59], and, in one particular study, the participants with MS reported improved reflection and understanding of their cognitive deficits as well as enhanced confidence and optimism after taking part in the programme [59]. Unfortunately, access to these programmes is often very limited, as they require considerable human resources as well as significant commitment and time investment from PwMS [59]. However, since they are simultaneously effective and low risk, the panel emphasised that cognitive rehabilitation programmes warrant consideration from clinicians and hoped that they become more widely accessible in MS clinics. Early initiation of interventions like these may ensure PwMS have the best chance of minimising the progression of cognitive impairment and its impact on their QoL.


Although cognitive impairment in MS is widely acknowledged by HCPs and in research, there seems to be a gap in MS care regarding proactively addressing it and its practical implications in day-to-day life. The challenging impacts of cognitive impairment are experienced by PwMS on a daily basis; they extend beyond the clinic and warrant adequate recognition and management.

There is optimism for the prioritisation of cognition in MS; with the recent shifts in healthcare approaches, patient priorities are being voiced and acknowledged more than they have been in the last decades. Patient engagement is becoming an increasingly active component of the drug development cycle, and meetings between various stakeholders discussing PwMS priorities have become more commonplace. The latter play a crucial role in informing clinicians, other stakeholders and research about the need to address the care priorities of PwMS and HCPs and improve disease and QoL outcomes.

If prioritised as highly as physical disability in both the MS care and clinical drug development setting, and discussed proactively between HCPs and PwMS, the ‘invisibility’ of cognitive impairment can be lifted. Here, we have highlighted the discussions of an expert panel from the MS21 group who advocated for more open communication between PwMS and their HCPs regarding cognitive impairment and stressed that cognition should be considered a priority in any treatment management strategy. As part of this broader vision, they hoped to see further research concerning intervention practices for protecting cognition and cognition endpoints in drug development research. Furthermore, they recommended the development of educational resources for both HCPs and PwMS concerning cognitive impairment, its stigma and its impact as well as what can be done to best manage this aspect of the disease. The authors hope that the insights and perspectives shared in this symposium will contribute to a brighter future for the management and treatment of cognitive impairment in PwMS.