What types of MS are there?

The course of MS is different from one person to the next, and can be mild, moderate, or severe.

The nature of someone's MS only becomes apparent over time and under normal circumstances it is not possible to say at diagnosis how someone's MS will develop.

The course of MS is often classified into four internationally recognised types, although people's experience of the condition varies so widely that it is not always easily apparent which type of MS they have.

1: Relapsing Remitting (RRMS)
At diagnosis, the majority of people have this form of MS - relapses (also known as attacks or exacerbations) occur on average once or twice a year, with good or complete remission in between, but with a tendency for symptoms to persist or increase over time.

This is the most common form of MS at time of initial diagnosis. It affects approximately 85% of everyone diagnosed with MS.

2: Secondary Progressive (SPMS)
People with this type of MS experience an initial period of relapsing remitting disease, (see above) but this is followed by a steadily worsening disease course with or without occasional flare-ups, minor recoveries (remissions), or plateaus.
About 50% of people with relapsing remitting MS develop secondary progressive MS within 10 years of their initial diagnosis.

3: Primary Progressive (PPMS)
People with this type of MS experience a slow but steady worsening of their disease ('progression') from the start, with no distinct relapses or remissions. But there are variations in speed at which it progresses. There are also occasional plateaus and temporary minor improvements.
This type of MS is relatively rare - only about 15% of people with MS will get this form.

4: Progressive Relapsing (PRMS)
In this rare form of the disease, people experience progression from the start, but also experience relapses as well. The progression is the main factor however, and PRMS is considered to be largely similar to PPMS.

Benign MS
In some cases, people experience very occasional relapses, usually early on, with complete recovery - or remission - in between. They don't have any serious disability and further relapses are infrequent - in fact they can sometimes happen a number of years apart. By its nature, benign MS can only be diagnosed after a long period of time with little disease activity. About 25% of people turn out after a number of years to have this type of MS.