Multiple Sclerosis

What is multiple sclerosis (MS)?

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

Understanding the brain, spinal cord, and nerves

Thousands of nerve fibres transmit tiny electrical impulses ('messages') between different parts of the 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, and is needed for the electrical impulses to travel correctly along the nerve fibre.

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

What causes multiple sclerosis?

MS is thought to be an auto-immune disease. This means that chemicals and cells of the immune system, which normally attack bacteria, viruses, etc, attack part of the body. When the disease is active, parts of the immune system, mainly cells called T-cells, 'attack' the myelin sheath which surrounds the nerve fibres in the brain and spinal cord. This leads to small patches of inflammation.

Something may 'trigger' the immune system to act in this way. One theory is that a virus, or another factor in the environment, triggers the immune system in some people with a certain genetic make-up.

The inflammation around the myelin sheath stops 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 MS, many (multiple) small areas of scarring (sclerosis) develop in the brain and spinal cord.

How does multiple sclerosis progress?

Once the disease is triggered, it tends to follow one of the following patterns.

Relapsing-remitting form of MS

Nearly 9 in 10 people with MS have the common relapsing-remitting form of the disease. A relapse is when an episode ('attack') of symptoms occurs. During a relapse, symptoms develop (described below) and may last days, but usually last 2-6 weeks. They sometimes last several months. Symptoms then ease or go away (remit). You are said to be 'in remission' when symptoms have eased or gone away. Further relapses then occur from time to time.

The type and number of symptoms that occur during a relapse vary from person to person, depending on where myelin damage occurs. The frequency of relapses also varies. One or two relapses every two years is fairly typical. But, relapses can occur more or less often than this. When a relapse occurs, previous symptoms may return, or new ones may appear.

This 'relapsing-remitting' 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 usually 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. This is called 'secondary progressive MS'. Typically, about two thirds of people with relapsing-remitting MS will have developed secondary progressive MS after 15 years.

Primary progressive form of MS

In about 1 in 10 cases, there is no initial relapsing-remitting course. The symptoms become gradually worse from the outset, and do not recover. This is called 'primary progressive MS'.

Benign MS

In less than 1 in 10 cases, there are only a few relapses in a lifetime, and no symptoms remain permanent. This is the least serious form of the disease, and is called 'benign MS'.

Who gets multiple sclerosis?

About 1 in 1000 people in the UK develop MS. It can affect anyone at any age, although it is rare under the age of 10. It most commonly first develops between the ages of 20 and 40. MS is the most common disabling illness of young adults in the UK. It is twice as common in women as in men.

MS is not strictly an hereditary disease. However, there is an increased chance of MS developing in close relatives of affected people. For example, a mother, father, brother, or sister of a person with MS has about a 1 in 100 chance of developing MS (compared to about a 1 in 1000 chance in the general population).

What are the symptoms of multiple sclerosis?

Symptoms during a relapse

Many different symptoms are possible with MS. The symptoms that occur during a relapse depend on which part, or parts, of the brain or spinal cord are affected. You may have just one symptom in one part of the 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 include:

• Numbness or tingling in parts of the skin. This is the most common symptom of a first relapse.
• Weakness or paralysis of some muscles. Mobility may be affected.
• Partial loss, or blurring of vision. Double vision.
• Problems with balance and co-ordination.
• Tremors or spasms of some muscles.
• Dizziness.
• Problems with passing urine.
• Inability to have an erection in men.
• Difficulty with speaking.

Tiredness, and psychological symptoms such as mood swings and depression, are also common in people with MS.

Secondary symptoms

These are symptoms that may develop later in the course of the illness when some of the above symptoms become permanent. They include: contractures, urine infections, osteoporosis (thinning of bones), muscle wasting, and lack of mobility.

How is multiple sclerosis diagnosed?

Almost all of 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, you may have an episode of numbness in a leg, or blurring of vision for a few weeks, which then goes. It may have been the first relapse of MS, or just a 'one-off' illness that was not MS.

Therefore, a firm diagnosis of MS is often not made until two or more relapses have occurred. So, you may have months, or years, of uncertainty if you have an episode of symptoms, and the diagnosis is not clear.

Do any tests help?

In most cases, no test can definitely prove that you have MS 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.

An MRI scan (Magnetic Resonance Imaging) of the brain is the most useful test. This type of scan can detect small areas of inflammation and scarring in the brain which occur in MS. Although very useful in helping to make a diagnosis of MS, MRI scans are not always conclusive. A scan result should always be viewed together with the symptoms and physical examination. Since MRI scans became available, other tests 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 CSF (the fluid surrounding the spinal cord) in the lower part of the back. Certain protein levels are measured. Some proteins are altered in MS, although they can be altered in other conditions too.
• Evoked potential test. In this test, electrodes measure if there is slowing or abnormal patterns in the electrical impulses in certain nerves.

What are the treatments for multiple sclerosis?

There is no cure for MS, but treatments can often help. Treatments generally fall into four categories.

• Drugs that aim to modify the disease process.
• Steroid medication to treat relapses.
• Other drugs to help ease symptoms.
• Other therapies and general support to minimise disability.

Steroids (sometimes called corticosteroids)

A steroid is often prescribed if you have a relapse which causes disability. A high dose is usually given for a few days. This is often by injection into a vein each day for several days. Sometimes steroid tablets are used. Steroids work by reducing inflammation. A course of steroids will usually shorten the duration of a relapse. So, symptoms improve more quickly than they would otherwise have done. However, steroids do not affect the ongoing progression of the disease.

Other medicines to treat symptoms

Depending on the symptoms that develop, other treatments may be advised to combat the symptoms. For example:

• Anti-spasm drugs to ease muscle spasms.
• Painkillers are sometimes needed.
• Medicines can help with some urinary problems that may develop.
• Antidepressant drugs are sometimes advised if you develop depression.
• Drugs can often help with erectile problems which may develop.
• There is debate as to the benefits of cannabis for people with MS.

Other treatments, therapies and support

A range of therapies may be advised, depending on what problems or disabilities develop. They include:

• Physiotherapy
• Occupational therapy
• Speech therapy
• Specialist nurse advice and support
• Psychological therapies
• Counselling

What is the outlook (prognosis)?

It is difficult to predict at the outset how badly MS will affect an individual. Some very general statistics include:

• After 10 years from the first episode of symptoms, about half of people with MS have developed some form of permanent disability. But, about half will not have done.
• After 15 years, about half are unable to walk without assistance. But, about half are still walking independently.
• After 25 years, about half are confined to a wheelchair. But, about half are not. So, the common belief that all people with MS will quickly become wheelchair bound is a myth.

The life expectancy of someone with MS is reduced on average by 6-11 years compared to the general population. Death only rarely occurs directly as a result of MS. However, as with other disabling conditions, if you become immobile due to MS then you have more risk of developing life threatening infections such as pneumonia.

Further help and advice

This leaflet is only a brief introduction to MS. Further help, information, and advice is available from:

Multiple Sclerosis Society England

MS National Centre, 372 Edgware Road, Staples Corner, London, NW2 6ND
Helpline: 0808 800 8000 Web: www.mssociety.org.uk

Multiple Sclerosis Society Scotland

Ratho Park, 88 Glasgow Road, Newbridge, EH28 8PP
Helpline: 0808 800 8000 Web: www.mssocietyscotland.org.uk

Multiple Sclerosis Society Northern Ireland

34 Annadale Avenue, Belfast, BT7 3JJ
Helpline: 0808 800 8000 Web: www.mssocietyni.co.uk

Multiple Sclerosis Society Wales

Temple Court, Cathedral Road, Cardiff, CF11 9HA
Tel: 029 2078 6676 Web: www.mssociety.org.uk/wales/

Multiple Sclerosis Trust

Spirella Building, Bridge Road, Letchworth, Herts, SG6 4ET
Tel: 01462 476700 Web: www.mstrust.org.uk