Common Types of MS
On average, 80 percent of people with
MS begin with the relapsing-remitting form of MS (RRMS). What
distinguishes this type of MS from other types are the temporary
symptom flare-ups or "exacerbations" (also referred to as
relapses, attacks, or bouts), which typically last for one to
three months. These are followed by a complete or partial
Between relapses, many people may go
into remission for a year or more. During this time, they may
remain symptom-free, or only experience mild changes with
symptoms that did not fully remit following the exacerbation.
While symptoms may not appear or worsen between MS attacks,
changes do continue within the CNS. New treatments are now
available to help slow the damage caused by MS. (These
treatments are disucssed in the following section.)
Initially, people with RRMS often
- sensory disturbances (such as
numbness or tingling)
- optic neuritis (inflammation of the
optic nerve causing visual changes or loss; usually occurring
in one eye)
- diplopia (double vision; objects may
also appear to jump as a result of the eyes not properly
Fortunately, visual changes are often
temporary. Other initial symptoms with RRMS may include limb
weakness, clumsiness, fatigue, cognitive changes, bladder and
bowel problems, sexual difficulties, and Lhermitte's sign. The
latter is a tingling sensation that radiates down the spine and
into the limbs when the neck is flexed.
If untreated, more than 90 percent of
individuals with RRMS may eventually enter a second phase of
RRMS, known as secondary-progressive MS (SPMS), within 25 years.
This phase is reached when the person experiences a progressive
worsening of symptoms. SPMS may occur with or without
While the majority of individuals with
MS (80 percent) are diagnosed with RRMS, most of the other 20
percent fall under the heading of primary-progressive MS (PPMS).
This form of MS presents a gradual but steady accumulation of
neurological problems from the onset, without the presence of
relapses and remissions. Unlike RRMS, where women are three
times as likely to be diagnosed than men, PPMS is equally
divided between the genders.
Other types of MS exist, but these are
not as common. These include benign (little or no change after
20 years), progressive-relapsing MS (PRMS) (progressive course
from the onset with acute relapses), and malignant or fulminant
MS (rapidly progressive disease course).