There are four subtypes of the disease and it would be essential to differentiate these as management and treatment may differ for each type. The following are the 4 subtypes:
Relapsing-remitting MS (RRMS) is characterized by unpredictable relapses, which then fade away either partially or completely (remission) with no new signs of disease activity for months or years. Around 85 percent of people with MS are diagnosed with this type of MS.
Primary-progressive MS (PPMS) is characterized by a slow accumulation of disability, without any attacks. It may stabilize for periods of time, and even offer minor temporary improvement but overall, there are no periods of remission. Approximately 10 percent of people diagnosed with MS have PPMS.
Secondary-progressive MS (SPMS) follows a diagnosis of RRMS. Over time, distinct relapses and remissions become less apparent and the disease begins to progress steadily, sometimes with plateaus. About half of people with relapsing-remitting MS start to worsen within 10-20 years of diagnosis, often with increasing levels of disability.
Progressive-relapsing MS (PRMS) is the rarest course of MS, occurring in only about 5 percent of people diagnosed. People with this form of MS experience relapse with or without recovery and steadily worsening disease from the beginning.