What is secondary progressive multiple sclerosis (SPMS)?
In multiple sclerosis, the immune system attacks the brain, spinal cord and optic nerves. These make up the central nervous system, which controls everything we do. Damage from the attack disrupts signals to and from the brain, causing the symptoms of MS.
Secondary progressive multiple sclerosis (SPMS) follows the initial course of relapsing-remitting MS (RRMS). Some people who are diagnosed with RRMS eventually go on to have a secondary progressive course, in which neurologic function worsens over time and disability increases. According to estimates, in the United States, the prevalence of SPMS is 27–45 for every 100,000 members of the general population.
SPMS can also be described as 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 more disability over time, with or without relapses or new MRI activity) or without progression.
This graphic shows the kinds of disease activity that can occur in SPMS though each person's experience with SPMS is unique. As you can see in the graph, following a period of relapsing-remitting disease, your disability may increase over time, with or without evidence of disease activity (relapses or changes on MRI). You may also have occasional relapses, as well as periods of stability.
Common signs and symptoms of secondary progressive MS
If you have SPMS, you will experience a gradual, steady change in your ability to do things over time. But one person’s symptoms may progress differently or more rapidly than someone else’s. Symptoms of SPMS include:
- Bowel and bladder problems, such as urgent need to urinate
- Difficulty with walking and coordination
- Numbness or tingling
- Problems with cognition, such as learning, remembering information or processing it
- Spasticity or stiffness of the muscles
- Vision problems, such as double vision
Read more about these and other MS symptoms.
How do I know if my disease course is stable?
Your disease activity and progression should be evaluated at least once a year by your MS healthcare provider. The evaluation should include a discussion of your symptoms, a neurologic exam and possibly an MRI. Characterizing the course of your disease at different points in time helps you and your MS care provider discuss your treatment options and expected outcomes. For example:
- If you have SPMS that is active, you and your MS care provider might talk about starting treatment with a disease-modifying therapy to reduce the risk of a relapse.
- If you have SPMS that is active and progressing despite the medication you are taking, your conversation with your MS care provider might be about the potential benefits and risks associated with switching to a more aggressive treatment strategy.
- If you have SPMS that is not active but is progressing with increasing accumulation of disability, you and your MS care provider might focus on rehabilitation strategies to help improve your function and mobility, as well as promote safety and independence.
- If you have SPMS that is stable and is not active or progressing, you and your MS care provider might focus on rehabilitation and other symptom management strategies to help you maintain function.
Read more about the treatment of SPMS.
How does SPMS differ from the other disease courses?
If you have relapsing-remitting MS, you may go on to have SPMS. With this transition, the disease gradually changes from the inflammatory process seen in RRMS to a more steadily progressive phase with nerve damage or loss. As with RRMS, you can still experience relapses and new MRI activity.
When does RRMS become SPMS?
Before approved disease-modifying therapies were available, studies indicated that 50% of those diagnosed with RRMS would transition to SPMS within 10 years, and 90% would transition within 25 years. While MS experts agree that disease-modifying treatments have an impact on disease progression, it is too soon to tell the extent to which they alter or delay the transition to SPMS.
What are the causes of SPMS?
In general, the cause of MS is not known. Scientists believe MS — including SPMS — is triggered by a combination of factors. To identify the cause, research is ongoing in areas of:
- Immunology (the study of the body’s immune system)
- Epidemiology (the study of disease patterns in large groups of people)
- Genetics (understanding the genes that may not be functioning correctly in people who develop MS)
- Infectious agents (such as viruses)
Learn more about the possible causes of MS.
Because the transition from a relapsing-remitting course to a more progressive one is a gradual process, your healthcare provider will not be able to tell exactly when it is happening. A variety of strategies, including a careful history of the changes in your symptoms, neurologic examination and repeat MRI scans, help determine whether the transition to SPMS has occurred.
Read more about how SPMS is diagnosed.
Experiences of people living with SPMS
Read the blog posts of three people who have found better ways to live with SPMS.