Primary progressive multiple sclerosis (PPMS)
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Approximately 15% of people who develop multiple sclerosis (MS) are diagnosed with the primary progressive form of the disease, commonly known as PPMS. This is characterized by steadily worsening MS symptoms over time.
MS is a neurological disorder caused by inflammation that damages nerve fibers in the central nervous system, comprising the brain, spinal cord, and optic nerves. MS is classified into types based on how disease symptoms manifest and progress over time.
What is primary progressive MS?
Most people with MS initially experience a relapsing disease course characterized by times when symptoms suddenly worsen — called relapses or exacerbations — that are interspersed with periods of remission when symptoms ease and remain relatively stable over time.
By contrast, beginning at disease onset, people with PPMS experience gradual worsening of MS symptoms over time, without periods of remission where symptoms remain stable. Some people with PPMS may experience occasional relapses.
The disease in PPMS can be classified as active or nonactive, based on whether or not the patient experiences occasional relapses or has evidence of new disease activity on MRI scans. PPMS also can be classified as with or without progression, based on how disabling symptoms are accumulating over a period of time.
While all forms of MS are caused by the immune system erroneously attacking cells in the nervous system, people with PPMS tend to have less inflammation than those with relapsing forms of MS. These patients also tend to have fewer lesions in the brain, but more in the spinal cord, relative to other MS types.
Although relapsing MS is substantially more common in women than men, PPMS affects all genders at equal rates. Additionally, PPMS usually develops later in life than does relapsing MS, by about a decade, on average — most people with PPMS are diagnosed in their 40s and 50s, though earlier diagnoses can also occur.
Symptoms of PPMS
People living with PPMS can experience many of the same MS symptoms as those with relapsing forms of the disease, but weakness in leg muscles and difficulty walking tend to be more common in PPMS. Other common symptoms of PPMS include:
- fatigue
- numbness or other unusual sensations, referred to as dysesthesias
- vision problems
- spasticity, or abnormally tight or stiff muscles
- difficulty controlling the bladder and bowels
- cognitive and emotional challenges
The rate of disease progression in MS varies widely from person to person, but in general, symptoms accumulate more quickly in PPMS than in relapsing disease forms.
Diagnosis of PPMS
To be diagnosed with PPMS, a person must experience one year of continual disease progression — that is, at least 12 months of continuously worsening symptoms without periods of remission, in which symptoms ease.
The diagnosis also requires clinical testing (e.g., MRI scans) to confirm symptoms are a result of the immune system attacking the nervous system. For example, on MRI scans, lesions typically are visible as spots that are markedly brighter or darker than the surrounding area. Clinicians also may use a lumbar puncture, commonly called a spinal tap, to determine the levels of immune proteins in the cerebrospinal fluid, the liquid that surrounds the brain and spinal cord.
According to the McDonald criteria — the formal guidelines used to diagnose MS — PPMS may be diagnosed if at least two of the following three diagnostic criteria are present:
- At least one MS-like inflammatory brain lesion
- At least two MS-like inflammatory lesions in the spinal cord
- High levels of immune proteins in the cerebrospinal fluid — specifically, an elevated immunoglobulin G index or an oligoclonal band
A PPMS diagnosis can take a long time, especially in cases when neurologic symptoms have just begun. Diagnostic delays are usually longer in PPMS than in relapsing forms of MS.
Treatment of PPMS
In March 2017, Ocrevus (ocrelizumab) became the first treatment approved by the U.S. Food and Drug Administration for PPMS. While not a cure, Ocrevus was found to slow disability progression in people with PPMS in clinical trials, especially when treatment was started early in the course of disease.
A marketing authorization for Ocrevus was granted in the European Union in January 2018. The therapy is now approved in more than 90 countries, according to its developer, Roche.
To date, Ocrevus remains the only medication approved in the U.S. to treat PPMS. Other therapies are in development, with clinical trials ongoing to test new potential treatments.
In addition to disease-modifying therapy to slow disability progression, other medications may be given to help manage specific PPMS symptoms.
Outlook of PPMS
Because specific symptoms and rates of progression vary widely in MS, the prognosis of PPMS differs substantially from person to person. People with PPMS generally experience a faster accumulation of disabling symptoms — and, consequently, more pronounced difficulties in daily life — compared with those with relapsing disease forms.
When an individual is diagnosed with PPMS, it is recommended the person talk with doctors and other healthcare professionals to establish a treatment and care plan. In addition to medications, lifestyle adjustments such as exercise and quitting smoking may be recommended. Physical and/or occupational therapy also can help minimize muscle weakness and restore movement.
Multiple Sclerosis News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.
FAQs about primary progressive MS
Like other disease forms, primary progressive multiple sclerosis (PPMS) is not itself fatal, though it may increase the risk of certain life-threatening complications such as pneumonia. The average lifespan for people with multiple sclerosis (MS) is about five to 10 years shorter than that of the general population, though this gap continues to narrow as MS care improves. Of note, the time from disease onset to death is generally shorter in PPMS than in relapsing disease forms — but because PPMS also usually manifests later in life, overall life expectancy is similar in all MS types.
The gradual accumulation of neurological symptoms that characterizes primary progressive multiple sclerosis (PPMS) can cause substantial difficulties in day-to-day life. Some activities may become difficult or impossible to do independently. Without treatment, it takes about a decade on average for someone with PPMS to require an aid such as a cane or crutch to walk short distances, but disease-modifying treatment can slow disability progression.
Most people with multiple sclerosis (MS) initially experience a relapsing-remitting disease course that is characterized by periods of remission where symptoms do not worsen over time. By contrast, in primary progressive MS (PPMS) symptoms gradually worsen over time from disease onset. Consequently, symptoms tend to accumulate more rapidly in PPMS than in other disease forms.
Because disabling symptoms tend to accumulate more quickly in primary progressive multiple sclerosis (PPMS) than in relapsing types of the disorder, people with PPMS are generally more likely than those with other disease forms to rely on wheelchairs and other assistive devices to improve mobility and get around in day-to-day life. But in clinical trials, the median time from disease onset to requiring a wheelchair was nearly two decades for people with PPMS taking Ocrevus — the only disease-modifying treatment approved in the U.S. for this disease type — which represents a seven-year delay in the need for a wheelchair compared with treatment with a placebo.
Although primary progressive multiple sclerosis (PPMS) is characterized by a gradual worsening of symptoms without relapse activity, some patients may experience disease relapses, in which new inflammation in the nervous system causes symptoms to suddenly worsen and then ease. However, by definition, people with PPMS do not experience periods of remission where symptoms remain stable for long periods of time between relapses.
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