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`Types of MS | National Multiple Sclerosis Society
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`Types of MS
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`Four disease courses have been identified in multiple sclerosis: clinically isolated syndrome (CIS),
`relapsing-remitting MS (RRMS), primary progressive MS (PPMS), and secondary progressive MS
`(SPMS).
`AJ
`Diagnosed in 2000
`7Managing MS
`Getting the care you need
`
`Managing MS is an ongoing process, beginning with the very first symptoms and continuing throughout
`the disease course. It’s never too soon or too late to think about how to access high quality care.
`Knowing what to look for, where to find it, and how to work effectively with your doctor and other health
`professionals is essential to your health and quality of life.
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`While there is no way to predict with any certainty how an individual’s disease will progress, four basic
`MS disease courses (also called types or phenotypes) have been defined by the International Advisory
`Committee on Clinical Trials of MS in 2013: clinically isolated syndrome, relapsing remitting, secondary
`progressive and primary progressive. In 2020, the same committee published a clarifying paper,
`highlighting the need for time framing the modifiers “activity” and “progression” and guidance for using
`the terms “worsening” or “progression” to describe the disease.
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`Although not considered a course of MS, radiologically isolated syndrome (RIS) has been used to
`classify those with abnormalities on MRI of the brain and/or spinal cord consistent with lesions of MS -
`not explained by another diagnosis - and who also have no past or current neurological symptoms or
`abnormalities found on neurological exam. Often these individuals have had an MRI because of other
`symptoms, such as headache, and were found to have lesions that appear similar to those seen in MS.
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`A 2020 study found a little over half of people with RIS go on to develop MS within ten years. There are
`no specific treatment guidelines for RIS and additional research is needed to further define what factors
`increase the likelihood that someone with RIS will develop MS. Monitoring of MRI and neurological
`symptoms, and neurological examination are generally recommended to quickly identify changes. If the
`diagnosis is MS, treatment can be started early. Research interest in RIS is high and several studies are
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`ongoing, which could provide more guidance for monitoring and treatment.
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`Clinically Isolated Syndrome (CIS)
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`Types of MS | National Multiple Sclerosis Society
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`CIS is a first episode of neurologic symptoms caused by inflammation and demyelination in the central
`nervous system. The episode, which by definition must last for at least 24 hours, is characteristic of
`multiple sclerosis but does not yet meet the criteria for a diagnosis of MS because people who
`experience a CIS may or may not go on to develop MS.
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`When CIS is accompanied by lesions on a brain MRI (magnetic resonance imaging) that are similar to
`those seen in MS, the person has a high likelihood of a second episode of neurologic symptoms and
`diagnosis of relapsing-remitting MS. When CIS is not accompanied by MS-like lesions on a brain MRI,
`the person has a much lower likelihood of developing MS.
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`The 2017 diagnostic criteria for MS make it possible to diagnose MS in a person with CIS who also has
`specific findings on brain MRI that provide evidence of an earlier episode of damage in a different
`location and indicate active inflammation in a region other than the one causing the current symptoms.
`As MRI technology improves, the diagnosis of MS will be made more quickly and easily. In the
`meantime, individuals with CIS who are considered at high risk for developing MS may now be treated
`with a disease-modifying therapy that has been approved by the U.S. Food and Drug Administration
`(FDA) for that purpose. Early treatment of CIS has been shown to delay onset of MS.
`
`Read More About CIS
`Relapsing-remitting MS (RRMS)
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`RRMS – the most common disease course – is characterized by clearly defined attacks of new or
`increasing neurologic symptoms. These attacks – also called relapses or exacerbations – are followed
`by periods of partial or complete recovery (remissions). During remissions, all symptoms may disappear,
`or some symptoms may continue and become permanent. However, there is no apparent progression of
`the disease during the periods of remission. RRMS can be further characterized as either active (with
`relapses and/or evidence of new MRI activity over a specified period of time) or not active, as well
`as worsening (a confirmed increase in disability following a relapse) or not worsening.
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`Approximately 85 percent of people with MS are initially diagnosed with RRMS.
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`This graphic shows the kinds of disease activity that can occur in RRMS over time; however each
`person's experience with RRMS will be unique. Following a relapse, the new symptoms may disappear
`without causing any increase in level of disability, or the new symptoms may partially disappear,
`resulting in an increase in disability. New lesions on MRI, as shown by the arrows, often occur as part of
`a relapse. However, new MRI lesions indicating MS activity may also occur without symptoms of which
`the person is aware.
`
`Learn More About RRMS
`Secondary progressive MS (SPMS)
`
`SPMS follows an initial relapsing-remitting course. Some people who are diagnosed with RRMS will
`eventually transition to a secondary progressive course in which there is a progressive worsening of
`neurologic function (accumulation of disability) over time. SPMS can be further characterized as
`either active (with relapses and/or evidence of new MRI activity during a specified period of time) or not
`active, as well as with progression (evidence of disability accumulation over time, with or without
`relapses or new MRI activity) or without progression.
`
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`This graphic shows the kinds of disease activity that can occur in SPMS over time; however each
`person's experience with SPMS will be unique. SPMS follows after relapsing-remitting MS. Disability
`gradually increases over time, with or without evidence of disease activity (relapses or changes on MRI).
`In SPMS, occasional relapses may occur, as well as periods of stability.
`
`Learn More About SPMS
`Primary progressive MS (PPMS)
`
`PPMS is characterized by worsening neurologic function (accumulation of disability) from the onset of
`symptoms, without early relapses or remissions. PPMS can be further characterized as
`either active (with an occasional relapse and/or evidence of new MRI activity over a specified period of
`time) or not active, as well as with progression (evidence of disability accumulation over time, with or
`without relapse or new MRI activity) or without progression.
`
`Approximately 15 percent of people with MS are diagnosed with PPMS.
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`This graphic shows the kinds of disease activity that can occur in PPMS over time; however each
`person's experience with PPMS will be unique. PPMS can have brief periods when the disease is stable,
`with or without a relapse or new MRI activity, as well as periods when increasing disability occurs with or
`without new relapses or lesions on MRI.
`
`Learn More About PPMS
`Treatments for MS
`
`There are more than a dozen disease-modifying therapies approved by the U.S. Food and Drug Administration (FDA)
`to treat all types of MS. Each drug has an indication from the FDA for the type of MS it can be used to treat. There are
`currently more treatments available for relapsing forms of MS than progressive forms. Scientists around the world are
`actively working to find more effective treatments for progressive forms of MS -- and addressing the challenges of
`progressive MS is a primary target of the Society’s research strategy.
`Additional resources
`
`MS Classifications Revised- Momentum article
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`https://www.nationalmssociety.org/What-is-MS/Types-of-MS
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