Types of MS

The course of MS is unpredictable. Some people may feel and seem healthy for many years following diagnosis, while others may be severely debilitated very quickly. Most people fit between these two extremes.

Although every individual will experience a different combination of MS symptoms, there are a number of distinct patterns relating to the course of the disease:

Relapsing-remitting MS

In this form of MS there are unpredictable exacerbations or attacks(relapses) during which new symptoms appear or existing symptoms become more severe. This can last for varying periods (days or months) and there is partial or total recovery (remission). The disease maybe inactive for months or years. About 85% of people are initially diagnosed with relapsing-remitting MS. 

Primary progressive MS

Approximately 10% of individuals are diagnosed with this form of MS, which is characterised by a lack of distinct attacks, but with slow onset and steadily worsening symptoms. There is an accumulation of disability which may level off at some point or continue over months and years. 

Secondary Progressive MS

For most individuals who initially have relapsing-remitting MS, there is the development of progressive disability later in the course of the disease often with superimposed relapses and no definite periods of remission.

Progressive relapsing MS

Thisis the least common subtype (approximately 5%). Individuals show asteady neurologic decline with a clear superimposition of attacks. Theremay or may not be some form of recovery following these relapses, butthe disease continues to progress without remissions.

Benign MS

Somepeople live with MS for many years without accumulating disability.This group has so-called benign MS. It is the mildest form of MS thatis clinically apparent. People with benign MS have a minimal amount ofphysical disability after ten years or more of the disease.Early identificationof benign MS is important in deciding who should or should not takelifelong disease-modifying treatments.

However, benign MS cannot bediagnosed at the onset of the disease but only becomes clear over time.Moreover, long-term follow-up has found that many people with benign MSdo go on to develop progressive disease, and therefore labelling someoneas having benign MS too early in the disease course may be misleading.

Childhood MS

Thoughrare, there is an increasing number of children diagnosed with MSaround the world. Neurologists are finding that MS in children hasdifferent characteristics and to date, no therapies have been tested forbeing safe or effective for the treatment of children with MS. TheInternational Paediatric MS Study Group is helping to improve this knowledge.

Course of MS

Itis impossible to predict the course of MSaccurately for any individual,but the first five years give some indication of how the disease willcontinue for that person. This is based upon the course of the diseaseover that period and the disease type (ie relapsing-remitting orprogressive). The level of disability reached at endpoints such as fiveand ten years is thought to be a reliable predictor of the future courseof the disease.

Age at onset andgender may also be indicators of the long-term course of the disease.Some research has indicated thatyounger age at onset (under 16 years ofage)  implies a more favourable prognosis, but this must be tempered bythe knowledge that for a young adult living with MS for 20 or 30 yearsmay result in substantial disability even if the progresstowards disability is slow and in the first 10 or 15 years he or she isrelatively mildly affected. Other research has indicated that late onset(over 55 years of age), particularly in males, may indicate aprogressive course of the disease.

Read more inMS in focus – disease courses in MS