Disease Types in MS
In order to understand the way the symptoms behave in MS, it is important to understand the four disease types, which is a way of categorizing the various patterns of the disease.
Relapsing-Remitting MS (RRMS)
The vast majority of people (85 percent) presenting with MS are first diagnosed with RRMS. RRMS is characterized by periods of worsening (caused by acute inflammation) in which, typically, new symptoms appear. The relapses are followed by periods of remission, during which time the person fully or partially recovers.
Secondary Progressive MS (SPMS)
In this form of MS, a person who initially had relapsing-remitting MS begins to develop a slowly progressive worsening of neurological function, especially leg strength and walking ability. Within ten years, about 50 percent of people with RRMS will transition to SPMS.
Primary Progressive MS (PPMS)
This type of MS is characterized by a gradual progression of the disease from its onset with no remissions at all. About 10 percent of MS patients are in this category.
Progressive-Relapsing MS (PRMS)
This form of MS follows a progressive course from onset, punctuated by relapses. There is significant recovery immediately following a relapse, but between relapses there is a gradual worsening of symptoms. This form of MS is rare, accounting for only 5 percent of MS patients.
Fact
Other categories include malignant MS and benign MS. Malignant MS, which is also sometimes known as Marburg's variant, is characterized by an extremely aggressive course of the disease. It is extremely rare. Benign MS is considered a subgroup of RRMS and is characterized by a person who has had MS for fifteen or more years with few relapses and little, if any, disability.
You may note that RRMS and SPMS are not different diseases or different types of disease, but are, in fact, time points of the same disease. RRMS transitions into SPMS for a percentage of people with MS.
Since MS is so unpredictable, it is impossible to predict how the disease course will go in any one person. Thus, it is recommended that anyone diagnosed with the disease begin drug therapy right away.
