Multiple sclerosis

What is multiple sclerosis?

Multiple sclerosis (MS) is a disease where patches of inflammation occur in parts of your brain and/or spinal cord. This can cause damage to parts of your brain and lead to various symptoms (described below).

Patient picks for Limb weakness and numbness

Brain and nerves

Early brain scans can predict MS prognosis

Brain scans of people with early signs of multiple sclerosis can predict the long-term prognosis of the disease.

by Ashwin Bhandari

Brain and nerves

Cervical rib

About 1 in 100 people are born with an extra rib called a cervical rib. About 1 in 10 people who have a cervical rib develop thoracic outlet syndrome. This happens if the cervical rib squashes the nerves and blood vessels going into the arm. Treatment can include painkillers, physiotherapy and sometimes surgery to relieve the compression caused by, for example, a cervical rib.

by Dr Doug McKechnie, MRCGP

Understanding the brain, spinal cord, and nerves

Many thousands of nerve fibres transmit tiny electrical messages (impulses) between different parts of your brain and spinal cord. Each nerve fibre in the brain and spinal cord is surrounded by a protective sheath made from a substance called myelin. The myelin sheath acts like the insulation around an electrical wire. It is needed for the electrical impulses to travel correctly along your nerve fibres.

Nerves are made up from many nerve fibres. Nerves come out of your brain and spinal cord and take messages to and from your muscles, skin, body organs and tissues.

What causes multiple sclerosis?

The exact cause of multiple sclerosis (MS) is unknown. Inflammation that is enabled by the immune system is triggered by an abnormal response to environmental factors. This only occurs in those who are susceptible because of their inherited genes.

When the multiple sclerosis is active, parts of the immune system, mainly T cells, attack the myelin sheath which surrounds the nerve fibres in the brain and spinal cord. This is why these types of conditions are called demyelinating diseases.

The inflammation around the myelin sheath prevents the affected nerve fibres from working properly and symptoms develop. When the inflammation clears, the myelin sheath may heal and repair and nerve fibres start to work again. However, the inflammation, or repeated bouts of inflammation, can leave a small scar (sclerosis) which can permanently damage nerve fibres. In a typical person with multiple sclerosis (MS), many (multiple) small areas of scarring develop in the brain and spinal cord. These scars may also be called plaques.

What is multiple sclerosis like?

MS tends to follow one of the following four patterns.

Relapsing-remitting MS

Nearly 9 in 10 people with multiple sclerosis (MS) have the relapsing-remitting form of the disease. In a relapse, an attack (episode) of symptoms occurs. During a relapse, symptoms develop (described below) and may last for days but usually last for 2-6 weeks. They sometimes last for several months. Symptoms of MS then improve or go away which is remission. Further relapses then occur from time to time.

The type and number of symptoms that occur during a relapse of multiple sclerosis vary from person to person. The frequency of relapses also varies. Having one or two relapses every two years is fairly typical. However, relapses can occur more or less often than this. When a relapse occurs, previous symptoms may return, or new ones may appear.

The relapsing-remitting MS pattern tends to last for several years. At first, full recovery from symptoms, or nearly full recovery, is typical following each relapse. In time, in addition to myelin damage, there may also be damage to the nerve fibres themselves.

Eventually, often after 5-15 years, some symptoms may become permanent. The permanent symptoms are due to accumulation of scar tissue in the brain and to the gradual nerve damage that occurs. The condition typically then slowly becomes worse over time and can affect life expectancy. This is called secondary progressive MS. Typically, about two thirds of people with relapsing-remitting multiple sclerosis will have developed secondary progressive MS after 15 years.

Benign MS

10-15% of patients have benign relapsing-remitting MS or 'benign MS'. Benign MS is a variation of relapsing-remitting MS where relapses are very mild, there are very long periods between relapses and/or only a few relapses ever occur.

Secondary progressive form of MS

In this form of multiple sclerosis there is a steady worsening of your symptoms (with or without relapses). Many people with the relapsing-remitting form later develop this type of MS.

Primary progressive form of MS

Primary progressive MS occurs in about 1 in 10 people with multiple sclerosis. There is no initial relapsing-remitting course and the symptoms become gradually worse from the outset and do not recover.

How common is multiple sclerosis?

Multiple sclerosis (MS) is the most common disabling illness of young adults in the UK. About 1 in 500 people in the UK develop multiple sclerosis. It can affect anyone at any age, although it is rare in young children. It often first develops in people aged between 30 and 50. It is more than twice as common in women as in men.

Is multiple sclerosis hereditary?

Multiple sclerosis is not strictly an hereditary disease. However, you have an increased chance of MS developing if you have a close relative with MS. For example, if your mother, father, brother or sister has MS, then you have about a 2 in 100 chance of developing MS (compared with about a 1 in 500 chance in the general population).

What are the symptoms of multiple sclerosis?

Multiple sclerosis causes a wide variety of symptoms. Many people experience only a few symptoms and it is very unlikely that you would develop all the symptoms described here. Symptoms of MS are usually unpredictable.

MS symptoms may worsen gradually with time. More commonly, symptoms come and go at different times.

Multiple sclerosis relapses can occur at any time and your symptoms may differ within each relapse. Although relapses usually occur for no apparent reason, various triggers can include infection, exercise and hot weather. The symptoms that occur during a relapse depend on which part, or parts, of your brain or spinal cord are affected. You may have just one symptom in one part of your body, or several symptoms in different parts of your body. The symptoms occur because the affected nerve fibres stop working properly.

The more common symptoms of multiple sclerosis include:

Visual problems

The first symptom of multiple sclerosis for around one in four people with MS is a disturbance of vision. Inflammation (swelling) of the optic nerve can occur. This is called optic neuritis. This can cause pain behind your eye and also some loss of your vision. This usually only affects one eye. Other eye symptoms may include blurring of your vision or having double vision.

Muscle spasms and spasticity

Tremors or spasms of some of your muscles may occur in MS. This is usually due to damage to the nerves that supply these muscles. Some muscles may shorten (contract) tightly and can then become stiff and harder to use. This is called spasticity.

Pain

There are two main types of pain that may occur in people with multiple sclerosis:

• Neuropathic pain - this occurs due to damage to the nerve fibres. This can cause stabbing pains or a burning sensation over parts of your skin. Areas of skin may also become very sensitive.

• Musculoskeletal pain - this type of pain can occur in any of your muscles that are affected by spasms or spasticity.

Fatigue

Extreme tiredness (fatigue) is one of the most common symptoms of MS. This tiredness with multiple sclerosis is more than the tiredness expected after exercising or exertion. This fatigue can even affect balance and concentration. There are different treatments for fatigue which are often a combination of self-management strategies, physiotherapy and exercise.

Emotional problems and depression

People with multiple sclerosis might laugh or cry more easily, even for no reason. Also, many people with MS have symptoms of depression or anxiety at some stage. Acknowledging this and asking for support is important. Your GP can discuss the treatment options available.

Other symptoms of multiple sclerosis which may occur include:

• Numbness or tingling in parts of your skin. This is the most common symptom of a first relapse.

• Weakness or paralysis of muscles. Mobility may be affected.

• Problems with your balance and co-ordination.

• Problems with your concentration and attention.

• Tremors or spasms of some of your muscles.

• Dizziness.

• Problems with passing urine.

• Inability to have an erection.

• Difficulty with speaking.

Secondary MS symptoms

These are symptoms that may develop later in the course of the disease when some of the above symptoms become permanent. Symptoms including contractures, urine infections, bone fragility (osteoporosis), muscle wasting and reduced mobility may be experienced.

How is multiple sclerosis diagnosed?

Almost all the symptoms that can occur with MS can also occur with other diseases. It is often difficult to be sure if a first episode of symptoms (a first relapse) is due to MS. For example, an episode of numbness in a leg, or blurring of vision for a few weeks, may have been the first relapse of MS or just a one-off illness that was not MS.

A firm diagnosis of MS is often not made until two or more relapses have occurred. So, there may be months, or years, of uncertainty when there is an episode of symptoms and the diagnosis is not yet clear. This can be a very difficult time for many people.

Can you test for multiple sclerosis?

In most cases, no test can definitely prove that you have multiple sclerosis after a first episode of symptoms or in the very early stages of the disease. However, some tests are helpful and may indicate that MS is a possible, or probable, cause of the symptoms.

A magnetic resonance imaging (MRI) scan of the brain is a useful test. This type of scan can detect small areas of inflammation and scarring in your brain which occur in multiple sclerosis. Although very useful in helping to make a diagnosis of MS, MRI scans are not always conclusive, especially in the early stages of the disease. A scan result should always be viewed together with your symptoms and physical examination.

Since MRI scans became available, other tests for multiple sclerosis are now done less often. However, they are sometimes done and include:

• Lumbar puncture. In this test a needle is inserted, under local anaesthetic, into the lower part of your back. It takes a sample of some of the fluid that surrounds your brain and spinal cord. This is called cerebrospinal fluid (CSF). Certain protein levels are measured. Some proteins are altered in multiple sclerosis, although they can be altered in other conditions too.

• Visual evoked potentials test. In this test, electrodes measure if there is slowing or any abnormal pattern in the electrical impulses in the optic nerves.

Can multiple sclerosis be treated?

At present there is no cure for multiple sclerosis. However many symptoms of MS can be eased to improve quality of life and make living with MS more manageable. Treatments generally fall into four categories:

• Medicines that aim to modify the disease process.

• Steroid medication to treat relapses.

• Other medicines to help ease symptoms.

• Other therapies and general support to minimise disability.

Medicines that aim to modify the disease process

These medicines are known as immunomodulatory agents. They do not cure MS and they are not suitable for everyone with MS.

Fingolimod, Ponesimod, Teriflunomide, Diroximel fumarate and Dimethyl fumarate are the only tablet forms of disease-modifying treatment. All the others are given by injection.

Natalizumab, Alemtuzumab, Ofatumumab, Ublituximab and Ocrelizumab are given by injection and are used for patients with more advanced or active disease.

Newer medicines and combinations of medicines are also being developed and studied.

Studies have shown that these medicines reduce the number of relapses for some people. They may also have a small effect on slowing the progression of the disease. The exact way in which they work is not always clear but they all interfere with the immune system in some way.

As there is still some uncertainty as to the role of these medicines and how effective they are, guidelines have been drawn up as to when they may be prescribed on the NHS. A consultant neurologist will advise on which of the treatments are recommended. Each of the different disease-modifying medicines has pros and cons. The Multiple Sclerosis Trust (see under 'Further Reading', below) provides an MS Decisions page which is designed to help you decide which is the best medicine for you.

If any of these treatments are prescribed, further monitoring and review also happens. With the help of this monitoring, over time, it should become clear how effective the treatments are.

Steroids for multiple sclerosis (sometimes called corticosteroids)

A steroid is often prescribed if there is a relapse which causes disability. A high dose is usually given for a few days. Sometimes steroid tablets are used or the steroid may be given through veins. The steroids work by reducing inflammation. A course of steroids will usually shorten the duration of a relapse. This means that symptoms usually improve more quickly than they would otherwise have done.

However, steroids do not affect the ongoing progression of the disease.

Other treatments to improve MS symptoms

Depending on which symptoms develop, other treatments may be advised. For example:

• Anti-spasm medicines.

• Painkillers. There are specific types of painkillers which can improve neuropathic pain.

• Medicines which can help with some urinary problems that may develop.

• Antidepressant medicines.

• Medicines to help with erectile problems.

Cannabis-based products

NICE provided guidance on the use of cannabis-related medicinal products for muscle spasticity in MS. The guidance recommends that people with moderate-to-severe muscle spasticity (which has not responded to other treatments), may be offered treatment with a cannabis-based mouth spray called Sativex® for four weeks. If the symptoms improve by at least 20% in this time, longer-term treatment may be offered.

This treatment should be started and supervised by an MS specialist doctor. Find out more about this treatment in our separate leaflet called Cannabis-based medicinal products (Medicinal marijuana).

Other treatments, therapies and support

Other therapies that may be offered include:

• Physiotherapy.

• Occupational therapy.

• Speech therapy.

• Specialist nurse advice and support.

• Psychological therapies.

• Counselling.

Driving

If you drive a car or ride a motorcycle, you must tell the DVLA that you have multiple sclerosis. However you can continue to drive or ride a motorcycle as long as you can drive safely at all times.

Multiple sclerosis outlook (prognosis)

Multiple sclerosis affects different people in many different ways. This means that it is very difficult to predict your outlook (prognosis) if you have MS. There are currently no tests to predict how your MS will progress.

Many people with MS will be able to continue to walk and function at their work for many years after their diagnosis.

However, some people with MS do become disabled over time, and a minority become severely disabled.

The treatment of MS is a rapidly developing area of medicine. The research into newer and better disease-modifying treatments brings a great deal of hope that the outlook for people with MS will continue to improve in the future and hopefully slow the progress of symptoms. The specialist who knows your case can give more accurate information about the outlook for your particular situation.