Tag Archives: biological

Cognition and mental health

Suicidal ideation and suicide in MS

Mental health problems and suicide are the underbelly of MS, the elephant in the consulting room. I have attempted to discuss these topics in a way that is not too dark, based on data from a 2026 systematic review. Please be aware, however, that the content may still be upsetting.

Key points

  • The suicide rate among people with MS is roughly twice that of the general population.
  • Several biological, psychological and social factors contribute to suicide risk:
    • depression and anxiety: a biological basis for these comorbidities exists in MS
    • MS disease-related factors: increased disability, disease duration and progression; life-changing symptoms
    • socio-demographic factors: age, male sex, living alone, education level
    • social and existential factors: loneliness, social exclusion and low perceived social support; loss of purpose and meaning; financial strain; fear of stigma.
  • Thoughts of ending one’s life – ‘suicidal ideation’ – precede suicide attempts; effective screening tools exist, are quick to complete and can identify patients at risk of suicide.
  • Systematic screening is not optional but should be part of the basic standard of care.
  • Suicide prevention in MS requires participation by the clinic, the patient (and their family) and the health system.
  • If you or someone you know is having thoughts of suicide, please reach out for help. Support groups are available.

The problem we avoid talking about …

MS is a chronic, unpredictable and often disabling neurological condition. People with MS know this, and as a result they carry a psychological burden that is usually overlooked in a 15-minute annual outpatient appointment. Mental health problems and suicide are the elephant in the MS consulting room. They sit quietly alongside the disability progression conversation, the drug treatment switch discussion, and the “How are things at home?” question that healthcare professionals (HCPs) often forget to ask.

How common are suicidal ideation and suicide in MS?

Suicidal ideation – thoughts of ending one’s life, with or without a plan – is the single most important precursor to suicide attempts, and death by suicide among people with MS is far more common than most HCPs appreciate. A landmark Canadian study in 1991 found that suicide was the third most common cause of death reported in MS clinics.1 The proportion of deaths due to suicide among people with MS (15%) was 7.5 times the proportion in an age-matched general population (2%).

More recent work suggests that the suicide rate among people with MS is roughly twice that of the general population.2 A 2026 systematic review and meta-analysis of suicidal ideation in MS draws on 18 studies and more than 8,000 people with MS to provide a picture of how common it is, what drives it and where the gaps are in MS care.2 From these combined data, the authors estimate that one in five people (20%) in an MS clinic waiting room has considered suicide. This is higher than the 13% figure from a 2020 meta-analysis,3 and the authors suggest two plausible explanations:

  • an expanding evidence base that now includes more diverse settings
  • a real rise in suicidal ideation rates – perhaps linked to the COVID-19 pandemic, growing geopolitical instability and reduced stigma around reporting mental health symptoms.

Individual study prevalence ranged dramatically, from 8% in a Canadian cohort to 36% in an Iranian cohort. This is probably telling us something important about how context, culture, income level and healthcare infrastructure shape suicide risk.

In most high-income countries, lifetime suicidal ideation prevalence in the general population is around 9–10%. The recent 20% figure in people with MS2 is therefore roughly double that seen in the background population – a finding echoed by many independent studies.

Regional and temporal patterns

In the 2026 review, subgroup analysis based on country income level reported a pooled suicidal ideation prevalence of 17% among the 14 high-income countries compared with 32% in the countries with ‘upper-middle’ incomes (three studies from Iran and one from Brazil).2 This aligns with what we know about mental health inequities more broadly – poverty, housing insecurity, financial strain, limited access to psychiatric services, and stigma all worsen outcomes in lower-resource settings. (Please note, the ‘upper-middle income’ data in this review came from just two countries; therefore, we should be cautious about extrapolating to sub-Saharan Africa, South Asia or Latin America as a whole.)

Suicidal ideation prevalence figures published between 19911 and 20262 from many studies conducted across different regions of the world vary widely and may appear inconsistent. The 2026 figure of 20% still means, however, that roughly one in five people with MS has active suicidal thoughts, and global crises in the last five years may be masking an underlying deterioration that will only become visible in the next generation of studies.

Limitations of study data

The 2026 review has limitations that need to be acknowledged. Study methodologies vary widely: suicidal ideation is measured with different instruments and at different time points; diagnostic criteria for MS are inconsistently reported; variability between studies is high. The ‘20% prevalence’ figure from 2026 is therefore an estimate with uncertainty. What is not uncertain is that suicidal ideation is substantially more common in MS than in the general population, and that it is driven by modifiable factors and hence is preventable. 

Who is at risk of suicidal ideation among people with MS

No single risk factor predicts suicidal ideation in isolation. Suicide is the final common pathway of several biological, psychological and social factors. Consistent drivers can be grouped into four domains.2

1. Psychiatric comorbidity: depression and anxiety

Depression and anxiety are the most consistently reported risk factors for suicidal ideation in MS.2 Depression affects up to 50% of people with MS at some point, far exceeding the 14–21% figure in the general population. This matters because depression in MS is both more common and more severe than in the general population, and it is driven by a mixture of:

  • neuroinflammation and hormonal factors (depression in MS is not simply a ‘reaction’ to having MS – it has a biological basis)
  • lesion location, particularly in limbic and frontal lobe/cortex pathways
  • disease-modifying therapy (DMT) side effects (particularly with interferon therapy)
  • the psychological burden of uncertainty, disability and loss of role.

Anxiety, which is often under-recognised and under-treated in MS, frequently coexists with depression and independently elevates suicidal ideation risk.

2. Disease-related factors

Several disease features align with suicidal ideation across studies.

  • Greater disability – measured both by clinician-rated EDSS (Expanded Disability Status Scale) scores and by self-reported physical impairment. The latter may be a stronger predictor than EDSS scores, because it captures the subjective experience of living with impairment.
  • Longer disease duration – though this relationship is complex. Study results vary, suggesting that some patients adapt psychologically over time, probably depending how well they adjust to living with MS.
  • Progressive MS – higher suicidal ideation rates are found in people with more advanced MS when compared with the earlier relapsing–remitting phase. Many HCPs and healthcare systems think that once someone with MS becomes disabled, the disease is not modifiable. I hope landmark studies like ocrelizumab in PPMS (O’HAND study), siponimod in SPMS (EXPAND study) and tolebrutinib in non-relapsing SPMS (HERCULES study) change this perspective. 
  • Specific symptoms – fatigue, sleep disturbance, spasms, bladder and bowel difficulties, and speech and swallowing problems also correlate with suicidal ideation. Together, these symptoms erode quality of life.

3. Sociodemographic factors

The evidence here is more mixed.

  • Age – findings are inconsistent. Some studies identify older patients (≥ 65 years) as higher risk; others find younger people with MS more vulnerable. Both extremes carry risk for different reasons; younger recently diagnosed patients face a challenge to their identity and loss of envisioned future; older patients face accumulated disability and social isolation.
  • Male sex – some (but not all) studies find men at higher risk, consistent with general population data on completed suicide.
  • Unmarried status and living alone are both associated with increased suicidal ideation in multiple studies.
  • Education level – most studies suggest that higher educational attainment is protective (better health literacy, coping strategies, economic resources); one Iranian study found the opposite, perhaps reflecting unmet expectations or awareness of prognosis.

4. Social and existential factors

This domain is the easiest to miss in a busy MS clinic but most important to address.

  • Low perceived social support, from family, friends and significant others, is a consistent risk factor.
  • Loneliness and social exclusion – ‘feeling socially excluded’ strongly correlates with suicidal ideation.
  • Hopelessness and loss of purpose – perceived loss of control, loss of masculinity/femininity and failure to achieve an expected role contribute psychologically to suicidal ideation.
  • Challenges to faith or spiritual meaning – having a sense of purpose, comfort in faith, and church membership can all be helpful and protective (in those for whom they are important).  
  • Financial strain and anticipated stigma are particularly important in lower-resource settings.

Screening for suicidal ideation in the clinic

If 20% of people with MS experience suicidal ideation but only a small fraction volunteer it spontaneously, systematic screening is not optional but should be part of the basic standard of care. Effective screening tools exist, and they are quick to complete.

The Patient Health Questionnaire-9 (PHQ-9)

The PHQ-9 is the most practical and widely validated mental health tool for neurological conditions, including MS; it is particularly suited to detecting suicidal ideation. Item 9 of this 9-item self-report depression screen specifically asks about thoughts of self-harm or being better off dead. It takes under 3 minutes to complete and can be done in the waiting room or electronically before the clinic. Scores above 10 indicate clinically significant depression warranting action. A positive response to item 9 should trigger a suicide risk assessment. It could be argued that every MS clinic should administer the PHQ-9 at least annually, and at every unscheduled visit where there has been a relapse, a significant disability progression, a DMT change or a major life event.

The Beck Scale for Suicide Ideation (BSI)

The BSI is a 20-item instrument designed specifically for suicide risk. It is more detailed than the PHQ-9 and is better suited to psychiatric follow-up than to first-line screening.

The Beck Depression Inventory-II (BDI-II)

The BDI-II is a broader 21-item depression measure that includes a suicide item. This is often used in research settings but takes longer to complete than the PHQ-9 in a clinic.

The Hospital Anxiety and Depression Scale (HADS)

The HADS is my favoured option that captures both anxiety and depression domains. It does not, however, include a direct suicide item, so a ‘positive’ (i.e. high: 11−21) HADS score should always prompt a follow-up suicide-specific question.

What should you be asked if a screen is positive?

Clinicians often feel awkward asking directly about suicide. Evidence is unambiguous that asking about suicide does not increase the risk. A graded approach works well:

  1. ‘Have you had thoughts that life isn’t worth living, or that you’d be better off dead?’
  2. ‘Have you had thoughts of harming yourself?’
  3. ‘Have you thought about how you might do it?’ (plan)
  4. ‘Do you have access to the means?’ (access)
  5. ‘Have you taken any steps or made any preparations?’ (intent)

Presence of a plan, access to means, or preparatory behaviour indicates a high imminent risk and demands urgent psychiatric referral – ideally, the same day.

Suicide prevention: what can we do?

Suicide prevention in MS operates at three levels: the clinic, the patient and the system.

At the clinical level

  • Screen systematically. A good MS service should embed PHQ-9 into routine MS review and not rely on patients volunteering suicidal ideation. If I were setting up an MS clinic now, I would include PHQ-9 in routine screening and add it to the annual questionnaire that patients must complete before each clinic visit. 
  • Treat depression and anxiety aggressively. Depression and anxiety are the dominant modifiable risk factors. Selective serotonin reuptake inhibitors (SSRIs: sertraline, citalopram, escitalopram) are first-line, well-tolerated drugs and have no meaningful interaction with current DMTs. Cognitive behavioural therapy (CBT) – including web-based models – has a good evidence base in MS. We should reject the dogma that ‘of course they’re depressed, they have MS’ as a reason not to proactively manage depression.
  • Address symptom burden. Fatigue, pain, sleep disturbance, bladder dysfunction and spasticity are not just quality-of-life issues – they are suicide risk factors that need to be treated. Please make sure that your MS care team provides relevant support. 
  • Be alert at transition points. Diagnosis, relapse, disability milestones (losing the ability to walk, work or drive), DMT failure, and being labelled as having secondary progressive MS are all periods of elevated risk. 
  • Assess social support explicitly. Who do you live with? Who helps you? Who would you call at 3 am? Treat loneliness and social isolation as vital potential danger signs.
  • Restrict means where appropriate. Safe storage of medications, particularly in patients with large quantities of prescribed opioids, benzodiazepines or anticholinergics, can save lives. This conversation needs to be had with the patient, their partner and their family. 
  • Document and communicate risk. A named crisis contact, a safety plan, and timely communication with the GP or primary care physician should be standard practice.

At the patient and family level

  • Psychoeducation. Many people with MS don’t know that depression is a common and treatable part of MS – they assume sadness and hopelessness are inevitable. Naming and confronting depression and suicidal ideation helps.
  • Normalise help-seeking. The stigma of psychiatric care in MS remains real. Framing mental health as part of MS care, not something separate, reduces that barrier.
  • Involve family. Family members are often the first to notice a change – withdrawal, giving away possessions, changes in sleep. They need to be taught about what to watch for.
  • Build purpose and connection. Peer support groups (e.g. MS Society, Shift.ms, MS Trust, MS International Federation resources, National MS Society [US]), vocational rehabilitation, social prescribing, church attendance, volunteering and hobbies all buffer against hopelessness. Having a purpose in life and being productive reduce the likelihood of suicidal ideation.
  • Safety planning. A written safety plan – warning signs, coping strategies, people to call, reasons for living, means restriction – is a simple but evidence-based self-administered intervention. The Stanley-Brown Safety Plan is freely available online.

At the system level

  • Integrate mental health into MS services. A neuropsychologist or clinical psychologist embedded in an MS service should not be a luxury; it is the minimum standard for a condition where one in two patients develops depression. That said, most NHS MS clinics don’t employ a neuropsychologist, and referring people with MS for assessment and management takes time.
  • Address inequity. The doubled suicidal ideation prevalence in upper-middle-income countries2 is not inevitable. It reflects under-resourced mental health services, stigma, and financial barriers to care – all modifiable at a policy level.
  • Research under-represented populations. The Bazmi review2 of 14 high-income and three upper-middle-income countries openly discusses its limitations: it includes no data from low-income countries and none from most of Asia, Africa or Latin America, beyond a single Brazilian study. MS care cannot be evidence-based at a global level if the evidence is dominated by findings from high-income countries. More research is needed. 

The bottom line

If you are an HCP and are reading this, please remember that roughly one in five of your MS patients has had thoughts of suicide. Most of them have not told you. The dominant drivers – depression, anxiety, disability, symptom burden, loneliness, hopelessness – are either treatable or modifiable, and the screening tools are simple, brief and validated. Although suicidal ideation is common in people with MS, it is driven by modifiable factors and hence is preventable. Suicide in MS is not inevitable. It is, however, easy to miss. Every person with MS deserves a clinician who asks directly, listens without flinching, and acts on what they hear.

If you or someone you know is having thoughts of suicide, please reach out for help.

In the UK, Samaritans are available 24/7 on 116 123.

In the US, the 988 Suicide and Crisis Lifeline is available by call or text.

In other countries, the International Association for Suicide Prevention (IASP) maintains a directory of crisis services at iasp.info/crisis-centres-helplines/

You are not alone, and help is available.

References

  1. Sadovnick AD, et al. Cause of death in patients attending multiple sclerosis clinics. Neurology 1991;41:1193. doi.org/10.1212/WNL.41.8.1193.
  2. Bazmi E, et al. Global prevalence and risk factors of suicidal ideation in multiple sclerosis: a systematic review and meta-analysis. Health Sci Rep 2026;9:e72331. doi: 10.1002/hsr2.72331.
  3. Kouchaki E, et al. Prevalence of suicidal ideation in multiple sclerosis patients: meta‐analysis of international studies. Soc Work Pub Health 2020;35:655–63.

Cognition and mental health

Mental ill-health in MS: prevalence and causes

It is now well established that the burden of MS extends far beyond the purely neurological problems to include mental health.

Key points

  • Many patients with MS experience both anxiety and depression.
  • Other emotional and behavioural changes associated with MS include cognitive changes, apathy, inappropriate laughing and crying, euphoria, mania and bipolar disorder.
  • Physical symptoms like fatigue, sleep disturbances, concentration difficulties, numbness, tingling and dizziness may occur both in MS and in anxiety states, complicating diagnosis.
  • Unless severe anxiety symptoms are formally diagnosed as an anxiety disorder, individuals miss out on targeted treatments.
  • There is growing evidence that MS-related emotional changes are not necessarily a psychological consequence of living with a disability.
    • They may have a biological origin related to structural damage in the brain, caused by the MS disease process.
    • Brain imaging techniques that measure activity reveal how these brain networks function in real time.
  • Emotional changes sometimes occur as a side effect of medications used in the management of MS, including steroids used to treat MS relapses..

Background and introduction

Multiple sclerosis (MS) is a chronic, inflammatory and neurodegenerative disease of the central nervous system (CNS) that is typically defined by its physical manifestations, such as motor weakness, sensory disturbances and fatigue. However, the burden of MS extends far beyond the purely neurological problems to include cognitive changes and mental health disorders such as anxiety, depression, apathy, mania and uncontrolled laughter and crying.

Anxiety and depression in people with MS

Among the most prevalent mental health problems in MS is anxiety, a condition that for many years was overshadowed by the clinical and research focus on depression. Anxiety is not a secondary issue but a core component of the disease experience for many people with MS. Anxiety and depression in MS are closely related, with many patients experiencing both simultaneously. Indeed, the presence of depression in people with MS is a strong predictor of the future development of anxiety, and vice versa. Both conditions share common underlying psychological risk factors such as avoidant coping styles and low optimism as well as unhealthy behaviours like smoking or lack of exercise.

Many large-scale studies have shown that anxiety is more prevalent in the MS population than in the general population. Two meta-analyses published in 2017 and 2023 assessed more than 50 published studies; based on pooled results, they estimated that 22% and 36%, respectively, of people with MS experienced anxiety.1,2 The prevalence rates for depressive disorders in people with MS are about 20−30%. Further research, utilising the UK MS Register, suggests that more than half (54%) of the 4000 patients recorded in the database have experienced clinically significant anxiety and 47% have experienced depression.3

MH anxiety

The proportions of people with different levels of anxiety (normal, mild, moderate or severe) and who have a depression score of 8 or above (N = 1961). Data from UK MS Register.3

MH depression

The proportions of people with different levels of depression (normal, mild, moderate or severe) and who have an anxiety score of 8 or above (N = 2268).  Data from UK MS Register.3

By contrast, the lifetime prevalence of any anxiety disorder in the general population in the USA is around 29% (though the prevalence at a specific point in time is lower). Anxiety is also significantly more prevalent in MS than in many other chronic neurological conditions, suggesting a relationship that may be specific to the pathophysiology or lived experience of MS.

Psychiatric symptoms versus psychiatric disorders

A critical nuance in understanding the epidemiology of anxiety in MS lies in the distinction between clinically significant anxiety symptoms and formally diagnosed anxiety disorders. The two are related but not interchangeable, and the disparity between their prevalence rates reveals a crucial aspect of the clinical challenge. The 2017 meta-analysis that found a 22% prevalence for anxiety disorders also found a substantially higher (34%) prevalence of clinically significant anxiety symptoms. This discrepancy indicates that for every ten patients who meet the formal diagnostic criteria for a specific anxiety disorder, such as generalised anxiety disorder (GAD) or panic disorder, there are approximately 15 patients who experience a level of anxiety that is severe enough to cause distress and impair functioning but is not formally identified and diagnosed in a clinical setting. The result is that these individuals miss out on targeted interventions such as specific psychotherapies or drug treatment that they might otherwise receive.

This large population of symptomatic but undiagnosed individuals may exist for several reasons. First, there is considerable symptom overlap between anxiety and MS itself. Physical symptoms like fatigue, sleep disturbances, concentration difficulties, numbness, tingling and dizziness can be manifestations of either MS or an anxiety state, creating a diagnostic challenge for clinicians and confusion for people with MS. Second, both patients and clinicians may view anxiety as an ’understandable’ or ’normal’ psychological reaction to living with a chronic, unpredictable illness, rather than as a distinct, treatable clinical entity. Finally, the historical research emphasis on depression may have led to less routine screening for anxiety in clinical practice. As an MSologist, it is also essential to differentiate formal depressive disorders from clinically significant depressive symptoms, which are much commoner than disorders.

Among those who do meet the criteria for a formal disorder, GAD appears to be the most prevalent, followed by panic disorder and obsessive-compulsive disorder. Recognising the full spectrum of anxiety, from subclinical symptoms to formal disorders, is essential for developing effective screening protocols and ensuring that all people with MS experiencing anxiety receive appropriate care (see article on management of mental ill-health in MS).

Other emotional and behavioural changes

MS impairs neuropsychiatric function (the interplay between neurological and psychological functioning) in a similar manner to its effects on other neurological functions. Living with MS can result in personality changes and subsequent relationship problems.

Cognitive changes

Cognitive impairment (i.e. dysfunction), particularly slowed information processing speed, is a common, well-documented and debilitating feature of MS. Anxiety has a demonstrably detrimental effect on cognitive domains that are often already compromised in MS, such as attention and executive functions.

Apathy

Apathy, characterised by profound loss of interest, blunted affect and reduced motivation, is also common in MS, particularly advanced MS. It is often misdiagnosed as depression. Apathy is not merely a component of low mood but is linked to executive dysfunction. Predictors identified include depressive symptoms, poor global quality of life, and poor attention and information processing speeds, probably due to MS lesions in the frontal lobe.

Inappropriate laughing and crying

Pathological laughing and crying, also known as pseudobulbar affect (PBA), are common but under-recognised and undertreated symptoms of MS that can be highly distressing and embarrassing for the patient and their relatives. The sudden, involuntary and explosive expressions of laughter or crying characteristic of PBA are often disproportionate or unrelated to the individual’s underlying emotional state.PBA is also associated with cognitive and mood problems, though the sudden and disproportionate emotional reactivity differentiates it from depression. The clinical presentation is due to frontal lobe or brainstem damage resulting from MS, which disrupts motor control pathways for emotional expression.  

Rare affective changes

Euphoria and mania are relatively uncommon in people with MS but are often triggered by high-dose steroids used to treat MS relapses.

Bipolar disorder is significantly more common in people with MS than in the general population; please see the separate post/chapter on this. The diagnosis must be made and treated by psychiatrists and involves lifelong therapy. 

The biological basis of mental illness in MS

MS-related emotional and mood changes are not necessarily a consequence of disability; they are often intrinsic to the MS disease process. This was recognised by the French neurologist Charcot, who, in 1877, noted pathological laughing, weeping, euphoria and depression in his patients who had MS.

Anxiety as a manifestation of MS pathology

While the psychological stress of living with a chronic illness contributes to anxiety in MS, there is growing evidence that anxiety is not solely a reactive or psychological phenomenon. The same autoimmune attack that damages myelin and axons, leading to physical disability, also targets and disrupts the complex neural circuits responsible for mood regulation, threat perception and emotional processing. 

Neuroinflammation and demyelination (damage to nerve insulation) are directly implicated in the development of anxiety and other psychiatric disorders. MS lesions are not confined to areas of the brain responsible for motor and sensory function but also occur within the networks that govern emotion and mood.

Structural and functional brain changes

Research has shown that people with MS can develop gradual grey matter loss in brain regions involved in emotion and motivation, particularly the limbic system and the basal ganglia. The limbic system includes the hippocampus, amygdala and cingulate cortex, and it plays a central role in processing emotions. Changes in the shape of the hippocampus have also been observed.

MH limbic system

Primary components of the limbic system. Modified from Encyclopaedia Britannica Inc.

These structural changes are thought to contribute to the development of mood and anxiety problems in MS. When MS-related inflammation, demyelination (damage to nerve insulation) or atrophy affects these areas, the brain’s ability to regulate fear and emotional responses can be disrupted. This creates a biological vulnerability to anxiety. From a structural perspective, therefore, anxiety in MS can be viewed as a direct consequence of neurological damage, in the same way that damage to the optic nerve causes visual impairment, or damage to the spinal cord leads to motor weakness.

In people with MS, depressive symptoms are consistently correlated with the volume of lesions in the brain and the degree of damage to connections between the cortex and subcortex. Neuroimaging studies show an association between depression and damage in the frontal and temporal areas of the cortex. In contrast, PBA is associated with lesions in the brainstem.

Brain imaging techniques that measure activity, such as functional MRI (fMRI), help to explain how these structural changes translate into anxiety symptoms. Rather than only showing where structural damage exists, fMRI studies reveal how brain networks function in real time. One key process identified in anxious people with MS is ‘fear overgeneralisation’. This occurs when the brain reacts to safe or neutral situations as if they were dangerous. For example, an individual learns to associate a specific signal (e.g. a picture of a circle) with a negative outcome (e.g. a mild electric shock). Anxious individuals tend to ’overgeneralise’ this fear, responding with fear to a similar but harmless signal (e.g. an oval), thus expanding their perception of danger in everyday life.

fMRI studies show that this process mainly involves the hippocampus (which is responsible for comparing incoming new experiences with ‘learned’ memories of danger) and the anterior insula (which plays a key role in generating the physical and emotional feeling of fear). In MS patients with anxiety, the physical pathways connecting these two regions are often disrupted, so that accurate information from the hippocampus is less effectively communicated to the anterior insula. As a result, the anterior insula may generate strong fear responses even when a situation is only mildly threatening or even safe.

fMRI studies have also revealed that many MS patients exhibit greater brain responses or increased recruitment of key emotional regions (e.g. prefrontal cortex and amygdala) compared to healthy controls. This likely reflects compensatory mechanisms the brain deploys to limit the clinical expression of emotional symptoms. The damaged MS brain tries to cope.

Neurological versus psychological causes

MS can trigger primary psychopathology as a result of demyelination and damage to specific functional circuits within the brain, as described above. It can be challenging to differentiate primary organic issues from reactive psychological problems, which is why people with MS may be referred for psychiatric assessments. 

I have, however, also seen patients in whom the initial symptoms were psychiatric, e.g. depression or (rarely) mania, but who were later found to have MS. The link between MS-related CNS damage and emotional symptoms is based on lesion location and lesion burden. For example, MS patients with lesions affecting the functional parts of the brain (rather than the connecting structures) exhibit a higher burden of emotional symptoms than those with lesions confined to the spinal cord. Our emotions are part of brain function in a similar way to motor function. Therefore, it is not surprising that MS impacts emotions. 

Lesion location and emotional symptoms

The evidence for a direct correlation between lesion location and anxiety is inconsistent. Some researchers suggest that, unlike depression, anxiety in MS may be driven more by psychosocial pressures and the psychological reaction to the illness rather than by focal brain damage. This discrepancy does not necessarily invalidate the biological basis of anxiety in MS. It may be that anxiety is related to more diffuse or subtle pathological changes, such as microstructural damage in white matter tracts or widespread neuroinflammation, that are not easily captured by conventional MRI lesion analysis. It is also possible that the broad distribution of the brain’s anxiety circuits means that damage to any number of different locations could produce a similar clinical outcome, making it difficult to pinpoint a single ’anxiety-causing’ lesion location. 

Other contributing factors

Emotional changes may occur as a side effect of medications used in the management of MS, including certain disease-modifying therapies. People with MS are also susceptible to the effects of the menopause, seasonal affective disorder and comorbidities associated with depression and anxiety, such as alcohol and other substance misuse disorders. It is advisable, therefore, to have a complete assessment before having a mood disorder labelled as being due to MS. 

Anxiety in MS may also be caused by high-dose corticosteroids, which are the standard treatment for MS relapses. Steroids have significant neuropsychiatric side effects, including anxiety, mania, insomnia and psychosis. For someone with MS already dealing with the stress of a relapse, the addition of steroid-induced anxiety can be particularly distressing.

‘Prodromal’ MS and psychiatric symptoms

Psychiatric comorbidities, such as anxiety and depression, have historically been viewed as consequences that follow the diagnosis of MS. Recent research, however, points to the existence of an ‘MS prodrome’, during which anxiety and depression occur years before the first classical neurological event.4 Increased rates of anxiety are a significant feature of this prodromal phase, suggesting that anxiety and/or depression may be early signs of MS, not merely a consequence. This body of recent research supports the idea that psychiatric symptoms in MS have a biological origin. This is most likely driven by the same low-level, diffuse neuroinflammatory and neurodegenerative processes that are smouldering away in the CNS long before the first eloquent MS lesion.

References

  1. Boeschoten, RE et al. Prevalence of depression and anxiety in multiple sclerosis: A systematic review and meta-analysis. J Neurol Sci 2017;372:331−341.
  2. Zhang X et al. The prevalence and risk factors of anxiety in multiple sclerosis: A systematic review and meta-analysis. Front Neurosci 2023;17:1120541.
  3. Jones KH, et al. A large-scale study of anxiety and depression in people with multiple sclerosis: a survey via the web portal of the UK MS Register. PLoS ONE 2012;7:e41910.
  4. Ruiz-Algueró, M et al. Health care use before multiple sclerosis symptom onset. JAMA Netw Open 2025;8:e2524635.
Treatment strategy

Do I understand the concepts of treat-2-target and NEDA?

Has anyone discussed a treatment target with you, including the need to rebaseline your disease activity? Have the concepts of preventing end-organ damage to the central nervous system (the ‘end-organ’ in MS) and brain volume loss or atrophy been broached?

Key points

  • Achieving long-term remission is a well-established treatment target in MS and several other autoimmune diseases.
  • Key measures of MS disease activity are used to define composite treatment targets; they provide objective means for monitoring and decision-making.
  • To demonstrate a target of no evident disease activity (NEDA) requires a minimum of three criteria to be met: no relapses, no MRI activity and no disability progression.
  • More stringent definitions of NEDA targets have evolved and will continue to do so as new predictors of treatment response are developed.

If you are on a disease-modifying therapy (DMT), what is the objective or treatment target for your MS? This is another question to be answered before committing yourself to a specific treatment strategy.

Treat-2-target

Relapses and ongoing focal inflammatory activity on MRI (new or enlarging T2 lesions and T1 gadolinium-enhancing lesions [Gd-enhancing]) are associated with poor outcomes. This has led to the adoption of ‘no evident disease activity’ (NEDA) as a treatment target in MS. NEDA, or NEDA-3, is a composite of three related measures of MS disease activity: (i) no relapses, (ii) no MRI activity (new or enlarging T2 lesions or Gd-enhancing lesions) and (iii) no disability progression. NEDA is an important goal for treating individuals with MS.

When to rebaseline

To use NEDA as a treatment target in day-to-day clinical practice, it is advisable to be ‘rebaselined’ after the onset of action of the DMT you have been started on. The timing of the MRI to provide a new baseline depends on the DMT concerned. The recommendations for immune reconstitution therapies (IRTs) are very different from those for maintenance therapies. In the case of an IRT (for example alemtuzumab or cladribine, which are given as short courses), breakthrough disease activity can be used as an indicator to retreat rather than necessarily to switch therapy. Therefore, a rebaselining MRI should be delayed until after the final course of therapy, e.g. 2 years, or close enough to the time when a third, or subsequent course, can be administered.

Determining treatment failure: IRTs

Questions remain of how many treatment cycles need to be given before considering that a specific IRT has not been effective.

  • For alemtuzumab, the threshold is three cycles under NHS England’s treatment algorithm (based on their cost-effectiveness analysis). Alemtuzumab is a biological or protein-based treatment, so the risk of developing neutralising anti-drug antibodies increases with each infusion.
  • Cladribine on the other hand is a small molecule, so neutralising antibodies are not a problem and there is no real limit on the number of courses that can be given.
  • Although HSCT tends to be a one-off treatment, there are rare reports of people with MS receiving more than one cycle.

Please note there are potentially cumulative risks associated with multiple cycles of an IRT: secondary malignancies in the case of HSCT and persistent lymphopaenia with cladribine. 

Determining treatment failure: maintenance therapies

In comparison to IRTs, if you have disease activity on a particular maintenance DMT, and provided you have been adherent to your treatment, this is usually interpreted as a suboptimal response or non-response and it should trigger a switch to another class of DMT. 

A criticism of NEDA is the omission of so-called ‘non-relapse-associated disease worsening’ as a component of the treatment target (in addition to evidence of incomplete recovery from relapses). I refer to this disease worsening as smouldering MS. Worsening disability in the absence of relapses may have little to do with ongoing focal inflammatory activity. It may simply represent a delayed dying-off of axons and nerve fibres following earlier focal inflammatory lesions. As a result, many neurologists feel uncomfortable switching, or stopping a DMT, based simply on non-relapse-associated worsening disability. For more information, please see Getting worse – smouldering MS.

Beyond NEDA-3

The definition of NEDA is evolving with clinical practice. Some centres are now testing for brain volume loss (that is, brain atrophy) and/or increased neurofilament light chain (NFL) in cerebrospinal fluid (CSF) as part of the NEDA-3 treatment target. NEDA-4 builds on NEDA-3, by including the target of normalising brain atrophy rates to within the normal range. The problem we have found with this is that the measurement of brain atrophy in an individual with MS level is very unreliable. For example, dehydration, excessive alcohol consumption and some symptomatic medications can cause the brain to shrink temporarily. We, therefore, think that CSF NFL levels are a better treatment target, less prone to misinterpretation. Neurofilaments are proteins that are found in nerves and axons (nerve fibres) and are released in proportion to the amount of nerve fibre damage that occurs in MS. Normalising CSF NFL levels, which would indicate that nerve damage is stopped, is referred to as NEDA-5. From a scientific perspective, including a more objective end-organ biomarker makes sense and will almost certainly be incorporated into our treatment target in the future.  

The components of NEDA-recommended targets are expanding as our ability to measure predictors of treatment response grows.
CSF, cerebrospinal fluid; MRI, Magnetic resonance imaging; NEDA, no evident disease activity; NEIDA, no evident inflammatory disease activity; NFL, neurofilament light; PROMS, patient-related outcome measures.

End-organ damage

The combination of relapses, the development of new MRI lesions and brain volume loss over 2 years in clinical trials predicts quite accurately who will become disabled over the same time period. From a treatment perspective, it is important to stop relapses, new MRI lesions and brain volume loss if we are to prevent or slow down worsening disability. Therefore, we must go beyond NEIDA (no evident inflammatory activity), which refers to relapses and focal MRI activity, and normalise brain volume loss if we can. 

Alternatives to NEDA?

Many neurologists are critical of using NEDA as a treatment target in clinical practice, fearing that it encourages people with MS to take highly effective DMTs that they consider may be ‘more risky’ (see short summaries of the available DMTs for information about individual drugs). Such neurologists, therefore, promote a less proactive approach and allow for some residual MS disease activity, but at a lower level. This treatment target is referred to as minimal evidence of disease activity, or MEDA.

In my opinion, MEDA flies in the face of the science of focal inflammatory lesions being ‘bad’ and it is associated with poor short-term, intermediate and long-term outcomes. If most people with MS end up receiving so-called high-efficacy therapies because of breakthrough disease activity, then this is what they probably need, that is, to have their MS treated adequately. Compelling evidence has emerged from trials, large registries and real-world data that people with MS treated early with highly effective DMTs (flipping the pyramid) do better than those who have delayed access to more effective DMTs.1,2,3 You can find a short summary of some key findings on the MS Brain Health website.

Implementing NEDA in clinical practice

Please note that achieving long-term remission, or NEDA, is a well-established treatment target in other autoimmune diseases, such as rheumatoid arthritis, autoimmune kidney disease and inflammatory bowel disease. People with MS treated to a target of NEDA do better than those with breakthrough disease activity. I would therefore strongly encourage you to discuss this treatment target with your own MS neurologist. 

The flowchart below illustrates how we implement a treat-2-target of NEDA strategy. The important take-home message is that the treatment targets in MS have moved; goal-setting and the active monitoring of outcomes is now required to achieve these goals. 

Treat to target NEDA algorithm

Recommended approaches to implementing a treat-2-target of NEDA strategy, using maintenance ̶ escalation or immune reconstitution therapy (IRT). The dotted lines indicate that if treatment fails you can either switch within the class (maintenance or IRT) or reassess the strategy. From Giovannoni, Curr Opin Neurol.4
Alem, alemtuzumab; Clad, cladribine; DMF, dimethyl fumarate; Fingo, fingolimod; GA, glatiramer acetate; HSCT, haematopoietic stem cell transplantation; IFNβ, interferon-beta; Mitox, mitoxantrone; NEDA, no evident disease activity; Nz, natalizumab; Ocre, ocrelizumab; Ofat, ofatumumab; Teri, teriflunomide.

There is also a clear need to update the definition of NEDA regularly as new technologies become available and are validated as predictors of treatment response. I therefore envisage the definition of NEDA changing still further in future to include more objective measures, particularly ones measuring end-organ damage and the inclusion of patient-related outcome measures.

References

Stages of MS

What type of MS do I have?

MS has historically been classified into different subtypes, and this subdivision dictates what treatments you are eligible for. These MS disease subtypes are not supported biologically, however, and many MS neurologists are of the opinion that MS is one disease.1

Key points

  • The difference between relapsing MS and non-relapsing progressive MS is explained.
  • The stages of MS have different labels, for historical development and reimbursement reasons, but biologically MS is one disease.
  • From a treatment perspective, the key thing is to know if your MS is active or inactive.
  • Active MS can be differentiated from inactive MS by relapses, MRI evidence of disease activity and raised neurofilament levels in the cerebrospinal fluid.

Type of MS

You should be able to classify yourself as having either relapsing MS or non-relapsing progressive MS. Knowing what type of MS has been diagnosed and whether your MS is active or inactive will allow you to ask your MS neurologist questions about the MS treatments available to you. 

Around 85–90% of people with MS start with so-called relapse-onset MS, i.e. they have a definite attack of symptoms that is usually followed by a period of complete or incomplete recovery. A single attack may be labelled as a clinically isolated syndrome (CIS): it does not fulfil the current diagnostic criteria for full-blown MS, but it means someone is at risk of further attacks and hence of developing MS in the future.

EDSS, Expanded Disability Status Scale score
EDSS, Expanded Disability Status Scale score

Once you have more attacks, either clinically in the form of relapse or subclinically with new lesions on magnetic resonance imaging (MRI), then you are usually diagnosed as having MS. The diagram below illustrates the typical course of repeated relapses and remissions, with worsening disability over time, that characterises so-called relapsing–remitting MS (RRMS).

After a variable period, people with relapse-onset MS may notice worsening neurological function without improvement. This is called secondary progressive MS (SPMS) and it can occur with superimposed relapses (so-called relapsing SPMS [RSPMS]) or without relapses.

EDSS, Expanded Disability Status Scale score
EDSS, Expanded Disability Status Scale score

A small number of people with MS (10–15%) will present with worsening neurological function without a prior history of relapses; this is called primary progressive MS (PPMS).

Interestingly, some people with PPMS go on to have relapses, and this is referred to as progressive relapsing MS (PRMS).

EDSS, Expanded Disability Status Scale score
EDSS, Expanded Disability Status Scale score

Rarely, someone may present with worsening neurological function, similar to PPMS, but have a prior history of just one relapse. This is referred to as single-attack progressive MS (SAP), but most MS specialists classify these patients as having SPMS. 

In summary …

  • Relapsing MS captures all people with MS who are still having relapses, i.e. within the last 2 years, and includes RRMS, RSPMS and PRMS.
  • Non-relapsing progressive MS refers to SPMS and PPMS: these latter two groups should have no history of recent relapses, i.e. in the last 2 years.

To further confuse things, non-relapsing progressive MS used to be referred to as chronic progressive MS (see below). 

Why is this important?

Different DMTs are licensed for different types of MS, and many treatment guidelines specifically state the type of MS for which a particular drug can be used.

Is MS one or more diseases?

In the past, MS was regarded as one disease: either you had MS, or you did not. The stages were referred to as early relapsing MS or chronic progressive MS, but MS was still one disease. 

When disease-modifying therapies (DMTs) were developed, MS was split into multiple sub-types. This categorisation was driven by commercial considerations, and it allowed interferon-beta to be licensed in the US under the Orphan Drug Act. The classification of orphan disease in the US requires there to be fewer than 200,000 people with that diagnosis. Dividing MS into RRMS, SPMS, PPMS and later CIS ensured that each category met this criterion. 

Since then, PRMS and radiologically isolated syndrome (RIS) have been added as potential subtypes. These classifications tend to be arbitrary and overlap, but there is no biological basis to support MS being more than one disease. 

Is your MS active or inactive?

From a treatment perspective, it is important to know if your disease is active or inactive. In active MS, there is evidence of ongoing inflammation in the brain and spinal cord. If you are having relapses, are developing new lesions on MRI or have raised neurofilament (NFL) levels in your cerebrospinal fluid (CSF) or blood, your MS is active. 

Active MS responds to anti-inflammatory treatments; inactive MS is less responsive to currently licensed DMTs. 

Criteria for ‘active’ MS accepted by many MS health professionals. CSF, cerebrospinal fluid; NFL, neurofilament light.
*Some neurologists accept 24 months, 36 months or even longer when assessing MRI activity. There is no international consensus on the gap between the baseline and new MRI scan to define active disease.

The term progressive MS refers to the stage of MS when your disability gets worse – independent of relapses, and possibly of focal inflammatory lesions. I say ‘possibly’, because our current MRI scans don’t show new or enlarging microscopic lesions but only those that are larger than ~3–4 mm. NFL measurements in either the CSF or blood have the advantage of being additive and integrating inflammatory activity. In my experience, about one in ten patients classified as ‘inactive’ based on clinical and MRI activity is found to have active MS when CSF NFL levels are analysed. Unfortunately, however, many MS neurologists, regulators and payers do not accept this latest definition of MS disease activity because tests for NFL levels are currently not widely available. 

In conclusion, knowing the type of MS you have and whether your disease is active or inactive will allow you to discuss with your MS specialist the kinds of treatment available to you. 

References

Giovannoni G, et al. Smouldering multiple sclerosis: the ‘real MS’. Ther Adv Neurol Disord 2022;15:17562864211066751.