Overview of multiple sclerosis (MS)

If you have multiple sclerosis (MS), you probably already know your type. However, what you may not know are the differences between your type and the other types of MS.

Each type is unique and has different symptoms and treatment methods.

There are four main types of MS:

Research has shown that RRMS and PPMS are more similar than their symptoms reveal.

Keep reading to learn about these two types of MS and what the research has to say about their similarities and differences.


RRMS is the most common form of MS. As many as 85 percent of people with MS receive an initial diagnosis of RRMS. RRMS is characterized by flare-ups or attacks of inflammation in the central nervous system (CNS).

These flare-ups are followed by remission periods with improved or completely resolved symptoms. People who’ve been living with RRMS for 10 years gradually develop SPMS.

RRMS symptoms come on suddenly and include episodes of:

There are several disease-modifying therapies (DMTs) available to treat RRMS. Many of these can also be used to treat SPMS in people who experience relapses.

PPMS is characterized by a steady worsening of neurologic function without distinct attacks or remission periods.

This type of MS involves considerably less of the type of inflammation seen in RRMS, resulting in fewer brain lesions and more spinal cord lesions.

Ocrevus (ocrelizumab) is the only medication currently approved by the Food and Drug Administration (FDA) for treating PPMS.

New research and clinical trials are ongoing to find more treatments specifically for PPMS.

The following are some of the key differences between RRMS and PPMS:

Relapsing-remitting MS (RRMS)Primary progressive MS (PPMS)
RRMS is diagnosed earlier. Most people are diagnosed with RRMS in their 20s and 30s.PPMS is diagnosed later. Most people are diagnosed with PPMS in their 40s and 50s.
People with RRMS tend to have more brain lesions with more inflammatory cells.Those with PPMS tend to have more spinal cord lesions and fewer inflammatory cells.
RRMS affects women two to three times more often than men.PPMS affects men and women equally.
People with RRMS will likely have mobility issues, but these issues are more gradual.People with PPMS often experience more mobility issues and have more trouble walking.

In general, PPMS tends to affect the body’s ability to function more than RRMS does.

For example, those with PPMS may also find it more difficult to continue working because of their mobility issues and declining neurologic function.

As far as symptoms go, RRMS and PPMS are oftentimes very different from each other.

People with RRMS enter periods of flare-ups and remission, while those with PPMS are in a continual phase of deterioration.

However, recent research has shown through MRI scans that they have certain characteristics in common. This includes the amount of demyelination and the appearance of their brain lesions. More research is still needed to see if there are other links between RRMS and PPMS.

Talk to your healthcare provider if you would like more information on the differences between RRMS and PPMS.