Multiple Sclerosis.

Multiple sclerosis (MS) is a condition that can affect the brain and spinal cord, causing a wide range of potential symptoms, including problems with vision, arm or leg movement, sensation or balance.

It's a lifelong condition that can sometimes cause serious disability, although it can occasionally be mild.

In many cases, it's possible to treat symptoms. Average life expectancy is slightly reduced for people with MS.

It's most commonly diagnosed in people in their 20s, 30s and 40s although it can develop at any age. It's about 2 to 3 times more common in women than men.

MS is one of the most common causes of disability in younger adults.

Symptoms of MS.

The symptoms of MS vary widely from person to person and can affect any part of the body.

The main symptoms include:

• fatigue
• difficulty walking
• vision problems, such as blurred vision
• problems controlling the bladder
• numbness or tingling in different parts of the body
• muscle stiffness and spasms
• problems with balance and co-ordination
• problems with thinking, learning and planning

Depending on the type of MS you have, your symptoms may come and go in phases or get steadily worse over time (progress).

Types of MS.

MS starts in 1 of 2 general ways: with individual relapses (attacks or exacerbations) or with gradual progression.

Relapsing remitting MS.

Between 8 and 9 of every 10 people with MS are diagnosed with the relapsing remitting type.

Someone with relapsing remitting MS will have episodes of new or worsening symptoms, known as relapses.

These typically worsen over a few days, last for days to weeks to months, then slowly improve over a similar time period.

Relapses often occur without warning, but are sometimes associated with a period of illness or stress.

The symptoms of a relapse may disappear altogether, with or without treatment, although some symptoms often persist, with repeated attacks happening over several years.

Periods between attacks are known as periods of remission. These can last for years at a time.

After many years (usually decades), many, but not all, people with relapsing remitting MS go on to develop secondary progressive MS.

In this type of MS, symptoms gradually worsen over time without obvious attacks. Some people continue to have infrequent relapses during this stage.

About two-thirds of people with relapsing remitting MS will develop secondary progressive MS.

Primary progressive MS.

Between 1 and 2 in every 10 people with the condition start their MS with a gradual worsening of symptoms.

In primary progressive MS, symptoms gradually worsen and accumulate over several years, and there are no periods of remission, though people often have periods where their condition appears to stabilise.

Secondary progressive MS.

Many people initially diagnosed with relapsing remitting MS go on to develop a progressive form of the condition. This is called secondary progressive MS (SPMS). The main feature in secondary progressive MS is symptoms gradually worsen and accumulate over time, known as progression. It is called secondary progressive MS because the progressive phase develops following, or secondary to, the initial relapsing remitting phase. In SPMS, the severity and frequency of relapses decrease or even stop altogether, but the level of permanent changes in symptoms increases over time.

The rate at which symptoms become more severe varies, typically the changes are slow and gradual over a number of years, though for some it can be more rapid. There can also be periods of minor improvement or times when symptoms stay the same.

What causes MS.

MS is an autoimmune condition. This is when something goes wrong with the immune system and it mistakenly attacks a healthy part of the body – in this case, the brain or spinal cord of the nervous system.

In MS, the immune system attacks the layer that surrounds and protects the nerves called the myelin sheath.

This damages and scars the sheath, and potentially the underlying nerves, meaning that messages travelling along the nerves become slowed or disrupted.

Exactly what causes the immune system to act in this way is unclear, but most experts think a combination of genetic and environmental factors is involved.

Treatments for MS.

There's currently no cure for MS, but a number of treatments can help control the condition and ease symptoms.

The treatment you need will depend on the specific symptoms and difficulties you have.

It may include:

• treating relapses with short courses of steroid medicine to speed up recovery
• specific treatments for individual MS symptoms
• treatment to reduce the number of relapses using medicines called disease-modifying therapies

Disease-modifying therapies may also help to slow or reduce the overall worsening of disability in people with a type of MS called relapsing remitting MS, and in some people with types called primary and secondary progressive MS, who have relapses.

Unfortunately, there's currently no treatment that can slow the progress of primary progressive MS, or secondary progressive MS, where there are no relapses.