It's generally very difficult to predict the course of MS. The condition varies greatly in each individual but most people with MS can expect 95% of the normal life expectancy.
Some studies have shown that people who have few attacks in the first several years after diagnosis; long intervals between attacks; complete recovery from attacks and attacks that are sensory in nature (i.e. numbness or tingling) tend to have better outcomes in the long run.
People who have early symptoms of tremor, difficulty in walking, or who have frequent attacks with incomplete recoveries tend to have a more progressive disease course.
People with MS can expect one of four courses of disease
MS tends to take one of four clinical courses, each of which might be mild, moderate, or severe:
A relapsing-remitting course (RRMS) characterized by partial or total recovery after attacks (also called exacerbations, relapses, or flares). This is the most common form of MS. Seventy to seventy-five percent of people with MS initially begin with a relapsing-remitting course.
Secondary progressive (SPMS)
A relapsing-remitting course which later becomes steadily progressive. Attacks and partial recoveries may continue to occur. This is called secondary-progressive MS (SPMS). Of the 70-75% who start with relapsing-remitting disease, more than 50% will develop SPMS within 10 years; 90% within 25 years.
Primary progressive (PPMS)
A progressive course from onset. This is called primary-progressive MS (PPMS). The symptoms generally do not remit. Fifteen percent of people with MS are diagnosed with PPMS, although the diagnosis usually needs to be made after the fact when the person has been living for a period of time with progressive disability but not acute attacks.
A progressive course from the outset which is also characterized by obvious acute attacks. This is called progressive-relapsing MS (PRMS) and it is quite rare. Approximately 6-10% of people with MS appear to have PRMS at diagnosis.
Researchers are currently trying to identify more precise indicators of the prognosis or predicted disease activity.
The MS Information Sourcebook produced by the Information Resource Center and Library of the National Multiple Sclerosis Society. © 2001 The National Multiple Sclerosis Society. All rights reserved. Reproduced with permission.