Secondary Progressive Multiple Sclerosis

Secondary Progressive Multiple Sclerosis

Multiple sclerosis (MS) is an autoimmune disease in which the body’s immune system attacks and destroys myelin, a fatty substance that covers nerve fibers and is critical for their electric function. The resulting inflammation interferes with the ability of the nerves to send electrical signals between the brain and spinal cord and other regions of the body, and in turn, the loss of effective nerve communication leads to disease symptoms. Secondary progressive multiple sclerosis (SPMS) is a stage of MS that follows the initial relapsing-remitting form, or RRMS, in most patients.

Whereas RRMS is marked by periods of remission — times when disease symptoms become less severe — in SPMS, a person’s symptoms steadily worsen over time. There still may be symptom relapses, but changes in symptom severity are generally less drastic than in the RRMS stage and symptoms do not disappear even in the remission phases. SPMS can be classified as active or not active, based on whether the individual experiences disease relapses or has evidence of new brain lesions. It also can be classified as with or without progression, based on patterns of disability accumulation over time.


Nearly all people with RRMS eventually will develop SPMS. However, because of advancements in disease-modifying treatments, fewer people today develop SPMS than before, and the transition to SPMS occurs later. The median time to progression from RRMS to SPMS is about 20 years. Exactly what causes the progression from RRMS to SPMS isn’t completely understood, and there is no single test that defines when MS changes from RRMS to SPMS.

A diagnosis of SPMS typically is made after carefully reviewing the progression of the disease in the preceding months and years. Often, six to 12 months of progression must be noted before a person is considered to have progressed to SPMS. Whereas RRMS symptoms are thought to be driven by active inflammation, SPMS is driven by neurodegeneration, meaning nerve damage that worsens over time. Imaging of the brain generally reveals more new and/or inflammatory lesions in the brains of people with RRMS, relative to those with SPMS.

Burning sensation in the face

Some patients may experience trigeminal neuralgia (TN). TN affects the nerve that carries information from the face to the brain, causing a sudden shock-like pain and burning sensation. TN can be triggered by everyday activities, like brushing your teeth. Some may also experience glosso-pharyngeal neuralgia (GPN), which is similar to TN in terms of severity but is due to damage in the cranial nerve. GPN causes pain in the tongue, throat, ear, and tonsils, and is triggered by laughing, crying, or speaking.

Unprovoked laughing or crying

SPMS patients can have uncontrolled bouts of laughing or crying without any evident trigger. This is called the pseudobulbar affect (PBA) or emotional incontinence. PBA is due to lesions in the part of the brain that controls emotions, called the amygdala. PBA can be distressing and prove challenging at work, school, and in social life; patients having these emotional bursts should discuss them with their healthcare team.

Feeling of electric shocks along the spine

A sudden feeling of electric shock that runs down the spine and the legs is called Lhermitte’s sign, and is due to inappropriate communication between damaged nerves in the neck and the brain (demyelination and hyperexcitability). This damage causes the brain to interpret signals as pain when, in reality, no physical stimulus exists. Lhermitte’s sign is not restricted to MS; it can occur in other neurological conditions as well.


A recurring symptom among SPMS patients is dysesthesia, a word that means a feeling that is “not normal.” Dysesthesia includes painful, burning sensations that create a feeling of a tight hug, and is commonly called the MS hug. It comes as a tight band or girdle-like sensation usually around the waist or chest (ribs), but can also affect the neck or limbs. It can be brief or long-lasting.

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.

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