If you have a diagnosis of MS, you may be seeking to understand how it’s likely to progress. Learning what to expect might give you a sense of control and help you make more informed decisions about your day-to-day life.

However, describing or predicting MS progression isn’t always straightforward, as it affects people in different ways. In fact, scientists are still working to understand how MS progresses.

MS occurs when your body’s immune system mistakenly targets your central nervous system (CNS). This damages the myelin sheath around nerve fibers and the nerve fibers within. The damage disrupts or distorts the nerve impulses being sent down your spinal cord.

As the damage progresses, symptoms can become more severe. However, it doesn’t always progress in the same way, and symptoms don’t always become gradually more severe.

Until now, doctors have classified MS as different types, partly based on how they progress.

Clinically isolated syndrome (CIS)

CIS involves an isolated episode of neurological symptoms that may or may not recur. If it recurs, it will be a type of MS and no longer isolated.

Relapsing-remitting MS (RRMS)

RRMS involves periods in which symptoms worsen — called flare-ups or relapses — and then improve. Between relapses, the changes that cause symptoms don’t appear to progress. Eventually, it may progress to secondary progressive MS.

Over several decades, the course of RRMS will likely change and become more complex.

RRMS affects 70–80% of people with MS.

Secondary progressive MS (SPMS)

Some people with RRMS will go on to develop SPMS, a more aggressive form of MS. This generally happens within 10 to 25 years of the first diagnosis.

SPMS involves relapses followed by partial recoveries or periods of remission. In SPMS, MS doesn’t disappear between cycles but steadily worsens.

Primary progressive MS (PPMS)

PPMS has a slow and steady progression with no remission periods. There may be occasional plateaus in symptoms and minor improvements in function that tend to be temporary. The progression rate varies over time.

About 10% of people with MS have this type.

MS is a complex disease. It’s difficult to diagnose and hard to pinpoint when it starts and how it progresses before symptoms become visible.

Experts are starting to think about MS in terms of their phases.

Imaging studies have suggested that a lot of background disease activity occurs before symptoms appear. This is called the subclinical phase.

Some experts also proposed that there’s enough evidence to describe the following three phases:

  1. A high risk phase, when a person notices early symptoms that may be a sign of MS.
  2. A relapsing-remitting phase, when symptoms worsen during a flare and then improve or disappear for a while.
  3. A progressive phase, when symptoms become progressively more severe.

This reflects that the labels for different types of MS are not clear-cut. It also suggests it might be more useful to describe MS in phases rather than separate types.

For instance, RRMS probably begins long before a person notices any symptoms, so that a person who experiences CIS may, in fact, have RRMS. Around 85% of people with MS have a history of CIS. After 15–20 years, around half of people who have experienced CIS go on to develop SPMS.

Early stage or high risk phase

MS results from damage to the nervous system. Once the damage reaches a certain point or affects a specific part of the body or brain, symptoms may start to appear.

Common early symptoms of MS can include:

  • vision changes due to optic neuritis
  • numbness and tingling
  • fatigue
  • loss of balance
  • dizziness
  • pain
  • muscle stiffness or spasms
  • tremor
  • bladder problems
  • bowel problems
  • difficulty with thinking and remembering

If you have these symptoms, a doctor can determine whether you’re at high risk of developing MS based on your medical history and a physical exam.

But there’s no definitive test to confirm the presence of MS, and many of the symptoms also occur with other conditions, so the disease can be hard to diagnose.

Relapsing-remitting phase

For many people with MS, their symptoms will come and go over time.

They’ll experience flare-ups that may last weeks or months, followed by periods of remission, when they may not notice any symptoms for up to several years. During remissions, the disease doesn’t appear to progress.

Even among people with RRMS, the timeline varies widely between individuals.

Progressive phase

In this phase, MS symptoms become progressively worse, and a person may not experience any improvement or remission. Some people with MS never experience this.

In the past, doctors have talked about relapsing-remitting MS becoming progressive MS, but it may be that this is a stage that some people reach while others don’t.

In addition to adults, children and adolescents can receive a diagnosis of MS, known as pediatric-onset MS (POMS). The NMSS reports that 3–5% of all people with MS noticed symptoms that started before they were 16 years old.

In children, MS tends to progress differently than in adults. It begins more aggressively, and there’s a higher relapse rate early in the disease. Disease progression becomes slower over time, but people whose MS begins in childhood often reach the disability milestone at an earlier age than with adult-onset MS.

Children with MS tend to have the relapsing-remitting type rather than progressive MS.

The outlook for MS varies widely. Symptoms often become more severe over time, but not always. MS doesn’t follow any specific timeline or progression.

According to the National Multiple Sclerosis Society (NMSS), around 2 in 3 people with MS will retain the ability to walk throughout their lives.

If MS progresses to a more advanced stage, it can seriously affect your quality of life. For instance, walking, writing, speaking, and thinking can become difficult.

While rarely fatal, MS can shorten your life by up to 7 years. You may need a caregiver to help with everyday tasks.

If you have a diagnosis of MS, you’ll likely remain in touch with your healthcare team so that they can monitor your symptoms and change your treatment if MS seems to be worsening. Each person will have their own treatment plan.

Learn about Medicare’s coverage of MS treatment.

What are the stages of MS?

It’s hard to define or predict the stages of MS. In the past, doctors were more likely to refer to types, but some scientists now think it’s more realistic to talk about a subclinical phase, when damage is occurring in the body but with no symptoms, followed by:

  1. A high risk phase, when people start to have symptoms that could indicate MS.
  2. A remitting-relapsing phase, when symptoms come and go over time.
  3. A progressive phase, when a person no longer has periods with no symptoms.

How long does it take for a person with MS to reach disability?

This will depend largely on the individual. The NMSS notes that around two-thirds of people with MS will continue to be able to walk throughout their lives. However, MS can affect a person’s eyesight, thinking, mobility, and other functions, which could lead to disability. How quickly this happens, if it does, will vary widely.

Which type of MR progresses most rapidly?

PPMS involves a steady worsening of symptoms without remissions. It affects around 10% of people with MS.

Fulminant MS, also known as Marburg acute MS, is a subtype of MS that involves a rapid deterioration of the myelin sheath, the covering on the nerves that becomes damaged in MS. It can rapidly lead to disability.

Are there any ways to slow the progression of MS?

Various treatments for MS can help manage symptoms and slow its progression. Your doctor will help you find one that’s right for you. In addition, leading a healthy lifestyle with proper exercise, diet, and sleep will go a long way toward managing your MS.

MS can be difficult to predict, as it affects people differently. In some cases, a person’s symptoms may not worsen over time. For others, however, MS may progress rapidly and affect an individual’s ability to function in daily life.

It is essential to work with a doctor who will help you monitor your condition and adjust your treatment as needed over time.