Secondary Progressive Multiple Sclerosis (SPMS) is one of four internationally recognised forms of Multiple Sclerosis.
SPMS is characterised by a steady progression of clinical neurological damage with or without superimposed relapses and minor remissions and plateaux. People who develop SPMS will have previously experienced a period of Relapsing/Remitting Multiple Sclerosis (RRMS) which may have lasted anything from two to forty years or more. Any superimposed relapses and remissions there are, tend to tail off over time.
The following graph, showing level of disability over time, demonstrates two typical courses of SPMS.
From the onset of the Secondary Progressive phase of the disease, disability starts advancing much quicker than it did during RRMS though the progress can still be quite slow in some individuals. Despite the fact that the majority of people with RRMS will develop SPMS, only 25% of people with MS will need to use a wheelchair.
In the piece on the Expanded Disability Status Scale, the average amount of time spent at each disability score is detailed.
The majority of people with the RRMS, but not all, will eventually develop SPMS, but the time taken varies enormously. After 10 years, 50% of people with RRMS will have developed SPMS. By 25 to 30 years, that figure will have risen to 90%.
Secondary Progressive Multiple Sclerosis tends to be associated with lower levels of inflammatory lesion formation than in RRMS but the total burden of disease continues to progress. This is thought to be caused by higher levels of axonal loss.
At any one time, the Secondary Progressive form of the disease accounts around 30% of all people with multiple sclerosis.
Other forms of Multiple
Relapsing/Remitting Multiple Sclerosis
Primary Progressive Multiple Sclerosis
Progressive Relapsing Multiple Sclerosis
Multiple Sclerosis links:
What is the Course of MS?