Multiple sclerosis: Get informed

Multiple sclerosis (MS) is an inflammatory disease affecting the central nervous system (brain and spinal cord).

Multiple sclerosis: Everything you need to know

What is multiple sclerosis?


Multiple sclerosis (MS) is a progressive inflammatory disease in which the immune system attacks the protective myelin sheath covering nerve fibres, leading to nerve damage.
It is a chronic degenerative disease of the central nervous system (including the brain, spinal cord and optic nerves).
It affects over 130,000 people in the UK, of which almost 75% are women. It is the most common disabling neurological disease of young adults in the UK.

The axon is a fibrous extension of the neuron that conducts nerve impulses. Its protective sheath, myelin, allows information to be conveyed more rapidly to the brain. In multiple sclerosis, it is this sheath that is progressively destroyed, thus modifying the transmission of nerve impulses, resulting in a range of signs and symptoms. 

When myelin is attacked by the immune system, an inflammatory process takes place. This progressive demyelination affects many areas of the brain, which explains the variety of symptoms. However, subsequent repair processes are usually triggered: remyelination. This results in an improvement in affected neuron function, which explains the clinical recovery after certain flare-ups. On the other hand, if the myelin regeneration process is too impaired, neuron function may remain disturbed in the long term.

Demyelination, in the form of lesions or scars, triggers an inflammatory episode which results in a flare-up, or a period or new neurological symptoms or an increase in existing symptoms. These relapses can last from a few days to two or three weeks before gradually disappearing. Flare-ups can occur at a variable frequency: from several episodes per year to a few spaced several years apart. 

MS lesions, or areas of scarring (sclerosis), are located in the brain or spinal cord. They are visible as bright or dark spots on an MRI (depending on the type of MRI used), and indicate the location of scarring resulting from inflammation and remyelination.

MS is not fatal, but, on average, the life expectancy of MS patients is reduced by 6 to 7 years. This statistic includes severe forms where the disease is very aggressive and rapidly progressing. Thus, the majority of patients enjoy a longevity that is quite equal to that of the general population.

Types of multiple sclerosis

When MS occurs, it can take two different initial forms: 

  • Relapsing-remitting: This type of MS is characterised by clearly identified attacks or new or increasing neurological symptoms. These attacks, or relapses, are followed by periods of partial or complete recovery, also called remissions. During remission symptoms may disappear or continue and become permanent, though there is no apparent progression of the disease. Relapsing-remitting multiple sclerosis (RRMS) lasts on average from 10 to 15 years, after which it may develop into a more progressive form of the disease. RRMS usually appears around 25-35 years of age, and around 85% of people with MS are initially diagnosed with it.
  • Progressive: usually starting after the age of 40, this form of MS induces a slow and continuous worsening of neurological symptoms over a period of at least six months without relapses.

Primary Progressive Multiple Sclerosis (PPMS) begins, from the moment of diagnosis, with a steady worsening of symptoms, usually without a distinct attack or period of remission. It is a disabling form of the disease that usually occurs after the age of 40. PPMS tends to be more disabling than RRMS. The onset of irreversible disability is twice as high for PPMS as RRMS. This form accounts for 15% of cases at the time of diagnosis.

  • Secondary Progressive Multiple Sclerosis (SPMS) follows an initial relapsing-remitting diagnosis (RRMS). After years of progression, RRMS may develop into a secondary progressive stage: with this type of MS there are fewer relapses where symptoms worsen and then improve, but disability gets steadily worse.

Progression of MS

MS is different for everyone who has it; its manifestations and progression can change from person to person. Although statistically 50% of patients are partially dependent on their family or friends after seventeen years, the disease leads to severe disability in less than 5% of cases. According to the Charcot Foundation, the level of a patient's disability five years after the onset of the first symptoms can even predict the long-term course of MS. In fact, 70% of patients who are totally independent at this stage will remain so after fifteen years and 40% of them after twenty years.

The Expanded Disability Status Scale (EDSS) is a method of quantifying disability in multiple sclerosis and monitoring changes in the level of disability over time. It quantifies impairment in 8 functional systems and assigns a Functional System Score (FSS) for each of these functional systems. Approximately once a year, the neurologist assesses the following functional systems: 

  • pyramidal (muscle weakness or difficult moving limbs)
  • cerebellar (impaired coordination, loss of balance, tremor)
  • brainstem (problems with speech, swallowing and nystagmus)
  • sensory (numbness or loss of sensations)
  • visual function (problems with sight)
  • bowel and bladder function
  • cerebral function (problems with thinking and memory)
  • other

The EDSS score is measured on a scale of 0 to 10 and progresses by half a point depending on the number of functions affected and the degree of severity of the disability. It can be used to apply for an official disability card.


Many symptoms can appear from the onset of the disease:  

  • Motor difficulties: difficulty in performing certain movements, total loss of motility
  • Sensory problems: tingling, burning or numbness
  • Cerebellar problems: loss of balance or unsteady gait
  • Visual problems: sudden decline of uni- or bilateral vision (optic neuritis)
  • Fatigue: sudden tiredness or feeling of exhaustion
  • Impairment of cognitive functions and personality disorders 

These symptoms will evolve during flare-ups. Some symptoms may be very short term and disappear within a few hours.

  • Lhermitte’s sign: sudden "electrical" sensation that runs through the back and into the limbs, often mid-movement.
  • Transverse myelitis:  total loss of sensation and motor skills in the lower limbs and paralysis of the intestines and bladder
  • Useless hand syndrome: functional impairment of the hand leading to clumsiness of complex finger movements and loss of manual dexterity
  • Spasticity: stiffness, spasms and clonus
  • Musculoskeletal and chronic pain
  • Issues localised in the facial-cranial area: involuntary eye movements, troubles with speech (articulation, slurring), trigeminal neuralgia, facial paralysis, difficulty swallowing
  • Bladder problems: urinary urgency, incontinence or retention
  • Bowel problems: constipation, diarrhoea, lack of bowel control
  • Sexual issues
  • Mood and emotional problems: temporary mood changes, instability, anxiety, depression, affective disorders
  • Cognitive problems: problems with thinking, memory and attention, cognitive fatigue, visuospatial problems

Causes and risk factors

The exact causes of multiple sclerosis are still unknown. Some genes involved in immunity may be a predisposing factor for the disease. However, the presence of these genes is not enough to develop MS. It is therefore not a "genetic" disease in the classic sense of the term, because a single gene is not responsible for its occurrence. Studies have found that in the general population, the risk of developing MS is about 1 in 750-1000  

Multiple sclerosis, however, more frequently affects people of northern European descent. Genetic factors predisposing to MS have also been identified. Studies have made it possible to determine that a person with a sibling with MS has a 1 in 37 risk of developing the disease (compared with a 1 in 600 risk in the general UK population, or 1 in 330 risk in the global general population). Nevertheless, multiple sclerosis is not a hereditary disease: for a child having one parent with MS, the risk of developing the multiple sclerosis is very close to that of a child whose both parents are not affected by the disease.

Furthermore, MS is about two to three times more common in women than in men, suggesting that hormones (or specific genes on the sex chromosomes) may have a direct or indirect role in predisposition to the disease.

Finally, certain environmental factors could also be involved: low exposure to the sun leading to a lower synthesis of vitamin D, smoking, excessive consumption of animal fats, pollution or even infection with certain viruses such as rabies, herpes, measles, rubella, certain retroviruses such as HTLV-1, or the Epstein-Barr virus responsible for infectious mononucleosis, among others.

It should be noted that large epidemiological studies have been conducted on the hepatitis B vaccine and no causal link has been established with the occurrence of MS.

The origin of MS is therefore multifactorial and results from the interaction between genes and environment.


The variety of symptoms and the pattern of flare-ups can make diagnosis difficult. It usually takes two or more relapses, with at least partial remission, to confirm the diagnosis. The neurologist must also be satisfied that the myelin damage (occurring in at least two different places) is not the result of other conditions.

A multidisciplinary team must perform a full medical assessment to confirm the diagnosis: 

  • a neurological examination
  • a physical assessment evaluating muscle tone, reflexes, sensory functions, balance and mobility
  • an MRI to visualise lesions in the white matter (which contains myelin) of the brain, cerebellum and spinal cord.
  • a dilated-eye examination
  • possibly a lumbar puncture for cerebrospinal fluid analysis

If the diagnosis is confirmed, other tests may be prescribed before starting treatment: blood tests, ECG (electrocardiogram), Doppler ultrasound (echocardiography), chest X-ray, etc.

Diagnostic errors

The lack of a screening test specific to multiple sclerosis tends to cause a delay in diagnosis and sometimes confusion with other conditions. One in twenty patients suspected of having MS is, in fact, affected by a different disease. There are usually two cases of differential diagnoses in multiple sclerosis: neurological signs such as dizziness, visual problems or sensory problems and back pain with tingling or burning. As a result, the following conditions are often diagnosed: 

  • Fabry disease
  • Systemic lupus erythematosus
  • Behçet's disease
  • Sarcoidosis
  • Sjögren's syndrome
  • Lyme disease
  • Multifocal lymphoma
  • Neuromyelitis Optica (Devic's 's disease)
  • Multiple stroke
  • Vitamin B12 or folate deficiency

>> Multiple Sclerosis Diagnosis: Carenity Members Tell Their Story

Read Chrystele's testimonial: a Carenity member living with MS who had a long journey to diagnosis:

"Trust your first instincts! Keep insisting and make sure your doctor takes you seriously instead of just going from doctor to doctor hoping to find the “one” that's going to discover what’s wrong with you. Choosing the “right physician” is never simple and every misdiagnosis will only make your anxiety grow."


A background treatment is often prescribed to reduce the duration and intensity of relapses. This must be adapted to the specific form of multiple sclerosis.  In addition to this protocol, the medical management of MS is also based on the following principles:

  • Relief of flare-related symptoms using treatments which are not specific to multiple sclerosis
  • Functional rehabilitation to preserve the patient's independence for as long as possible and limit the complications linked to immobility
  • Psychological support
  • Education programmes

Background treatments

The aim of background treatment regimens is to reduce the frequency of relapses and thus the progression of impairment. They are indicated for relapsing forms with at least two relapses in the previous two years and for active secondary progressive forms.

Immunomodulators are prescribed as first-line treatment. These are beta interferons (BETAFERON, REBIF, AVONEX), substances produced naturally by the body to inhibit the multiplication of viruses and stimulate the activity of certain immune cells. According to the French Collège des enseignants de neurologie (College of Neurology Educators), they reduce the frequency of relapses by about 30-50%. Their tolerance is generally satisfactory, with the exception of flu-like symptoms and skin reactions a few hours after injection during the first three months of treatment. Glatiramer acetate (COPAXONE) may be prescribed if there is a contraindication to beta interferon. 

More recently, there are two oral treatments, AUBAGIO and TECFIDERA, which can also be used as a first-line treatment and which act through different mechanisms, again with an overall effectiveness comparable to the above-mentioned treatments.

Immunosuppressants (MITOXANTRONE, GILENYA, OCREVUS, AUBAGIO) are used as a second line of treatment or for aggressive forms meeting the following criteria:

  • a highly active form of the disease despite treatment with beta interferon
  • a form of severe, rapidly progressing, relapsing-remitting MS, characterised by at least two attacks in a year, associated with lesions on MRI. 

Among these immunosuppressants, natalizumab (TYSABRI), which contains a monoclonal antibody, has a selective immunosuppressive effect because it is a selective inhibitor of adhesion molecules. It prevents the migration of cells involved in inflammation of the central nervous system into the brain in MS patients. In clinical studies, this treatment has been shown to reduce the number of relapses and the formation and spread of brain lesions.

Treatments for relapses

Corticosteroids are also prescribed to reduce inflammation and reduce the duration of flare-ups. The dosage is usually high, and sometimes even given intravenously in large doses (up to 1000 mg of prednisone per day), which is called a "bolus" dose of corticosteroids. However, side effects can be numerous: excess energy, insomnia, water and salt retention, swelling of the face and torso, acne, muscle weakness, digestive problems.

Finally, plasmapheresis (plasma exchange) may be considered in the event that intravenous corticosteroid therapy fails. This process consists of replacing a large quantity of plasma with 4% albumin, a replacement product. Plasma contains a number of substances that can be toxic to the nervous system, including antibodies to myelin proteins. These antibodies may participate in the attack on myelin in inflammatory lesions in the brain and spinal cord.
The plasma exchange takes about three hours and usually needs to be done every two days for up to 5 or 6 exchanges.

Treatments for symptoms

Many symptoms such as fatigue, muscle spasms, pain or urinary problems can be relieved by medication or therapeutic treatments:

  • Fatigue: energy-saving techniques, adjustment of pace of life and amantadine
  • Spasticity: physiotherapy with muscle relaxants (baclofen or dantrolene) if it is diffuse; physiotherapy and intramuscular injections of botulinum toxin if the spasticity is focal.
  • Neuropathic pain: centrally acting analgesics (tramadol) or anti-epileptic psychotropic drugs (gabapentin, pregabalin, carbamazepine)
  • Bladder and bowel problems: anticholinergics, alpha-blocking or self-blocking depending on the type of symptom

Non-medicinal therapies

Physiotherapy is essential in the treatment of multiple sclerosis when the patient suffers from balance problems, stiffness or walking difficulties. A specialised physiotherapist will thus help to improve these problems and prevent them from worsening, as well as to learn how to live better with a disability.

Acupuncture, relaxation, self-hypnosis, meditation, sophrology or psychotherapy may also be beneficial. The management of MS must be multifaceted in order to support the patient in the best possible way.

Also noteworthy is the success of CBD-based products (cannabidiol, a natural derivative of cannabis) which help to reduce painful spasms. Experiments are also under way in several regions to test cannabis for therapeutic use.

Living with MS

According to the World Health Organization, quality of life is influenced by a person's physical health, psychological state, level of independence and social relationships. MS - like any chronic disease - can therefore have an impact. However, there are ways to manage the symptoms, anxieties and difficulties encountered in the social and professional environment.


MS mainly affects young adults starting their working lives. However, the disease does not need to hinder their integration into the workforce. 

Patients have every opportunity to pursue a professional career with responsibilities and advancement. This involves learning to adapt to the progression of the disease through job accommodation, periods of part-time work or reduced hours, or the recognition of disabled worker status. And if the symptoms finally make it impossible to carry out the work, various financial aids exist, such as the Personal Independence Payment, Attendance Allowance and Employment and Support Allowance.

Family and Friends

MS requires a continual process of adaptation and adjustment. And this is all the more frustrating because it is unpredictable. All it takes is one more relapse for an important body function to be suddenly impaired. Added to this are sometimes everyday symptoms such as fatigue, cognitive problems or speech difficulties. This situation can be difficult to manage for the patient as well as for his or her family and friends. MS often leads to anxiety, misunderstanding, anger or depression. In order to preserve the daily life and the bonds of affection between each person, communication is essential. Each person must have access to appropriate information so that any and all discussions are possible. There are many tools available to help patients discuss MS with their loved ones and with their children, such as the Multiple Sclerosis Trust’s site or the videos produced by the MS Society where puppets Annie and Dan explain talk about MS.

MS and intimacy

MS can often have an impact on relationships. Emotional relationships and sexuality can be shaken by fatigue, altered sensations, spasticity, tremors, sexual dysfunction or simply by the difficult emotional context (depressive state, partner-carer). It is essential to prioritise communication with one's partner and to be well supported. For example, it can be good to go to the neurologist together. This allows for questions to be asked about the disease and its impact on life as a couple. It is also important to not hesitate to discuss sexual problems with the neurologist, so that he or she can recommend the couple to a qualified sex therapist.

It is important to clarify that in the majority of cases MS does not prevent the arrival of a child. A pregnancy can be planned in consultation with the neurologist and a gynaecological team familiar with the condition. Pregnancy must be well planned so as to be able to stop the background treatments beforehand and to adapt medical care.

Physical activity

Proper physical activity is essential! Exercise helps to maintain muscular and functional ability, increase endurance, improve balance, but also to better manage fatigue and fight against depression. MS patients are therefore advised to take part in physical activity for half an hour, two to three times a week, in addition to physiotherapy. No activity is contraindicated! All kinds of sport can be practised in an adaptive and guided manner, whether it be rugby, archery, swimming, walking, gymnastics, etc.

It should be noted that a minority of patients experience an onset of symptoms when their body temperature rises. This is known as the Uhthoff's phenomenon and can occur in cases of sun exposure, fever or physical activity. It is by no means a progressive sign of the disease, but simply a temporary blockage of nerve impulses. The symptoms therefore cease as soon as body temperature returns to normal.

avatar Carenity Editorial Team

Author: Carenity Editorial Team, Editorial Team

The Carenity Editorial Team is made up of experienced editors and specialists in the healthcare field who aim to provide impartial and high quality information. Our editorial content is proofread, edited and... >> Learn more

Who reviewed it: Laurent Suchet, Neurologist

Neurologist, ex-Head of Clinic, Hospital Assistant at Marseille European Hospital. Particulary interested in patient care for people suffering with MS.

>> Learn more

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