Multiple Sclerosis (MS) is a chronic and complex disease with many concepts to understand.  The term Multiple refers to many and Sclerosis refers to plaques or scars.  These scars are also referred to as lesions as seen on MRI pictures of the brain and spinal cord.  As early as 1838 there are records of autopsies performed on people who demonstrated symptoms we now associate with MS.  Those who completed the autopsies noted the many scars and hardened areas throughout the brain and spinal cord and recorded the observations by drawing pictures. MS is referred to as a demyelinating disease with the damage occurring to the myelin sheath of the nerves of the brain, spinal cord and optic nerves and/or cells that produce and maintain them. Although other names have been used to describe the disease, MS is most commonly used today.

The diagnosis of MS is primarily based on the clinical history and presentation of a person’s symptoms. The history of symptoms is combined with a complete neurological examination and diagnostic tests are performed to determine if the person meets criteria for diagnosis of MS or if there are other diagnoses that should be considered. For the diagnosis of MS, symptoms must occur at different time periods and be from different areas of the Central Nervous System (CNS) which includes the brain, spinal cord and optic nerves. Tests to support or confirm the diagnosis of MS often include:  MRIs of the brain and spinal cord, diagnostic studies and blood tests to rule out other conditions, and obtaining spinal fluid for analysis by lumbar puncture. There are specific criteria that the MS Specialists use to formulate and confirm the diagnosis of MS based upon the combination of the clinical history, neurologic examination and diagnostic testing.

The most commonly cited estimate of people who are diagnosed with MS in the United States is 400,000. More recent studies have estimated the prevalence to be slightly higher, at over 570,000 people having MS.  Global estimates of people having MS range from 2.3 million to 2.5 million. Most people are diagnosed with MS between the ages of 20 and 50 years with the peak age being 30 years.



To understand MS you must start with a basic understanding of our body’s immune system. The immune system is a powerful network of glands, blood cells, tissues, etc., that offers a first line of defense to protect the body from unwanted invaders such as viruses, bacteria, toxins, etc.  If these invaders are left unchecked, they cause infections and disease in our bodies. In the science world these invaders are often called antigens.  When an antigen enters the body, the immune system recognizes it as not belonging to us and launches an attack to destroy it with the goal to protect us.  When the immune system launches an attack on the body’s own healthy cells by mistake, it is classified as autoimmune. Scientist refer to this as “attack on self” and it can happen most anywhere in the body. There are more than 80 types of autoimmune diseases and MS is on this list.

Multiple Sclerosis is classified as an autoimmune disease and the attack occurs on the nerves in the central nervous system (CNS) that consists of the brain, spinal cord and optic nerves.

In MS, the immune system is triggered by an unknown antigen and launches an attack on the protective covering (myelin sheath) of nerve cells. The myelin sheath in an insulating layer that forms around the nerves and is made up of fatty substances and proteins. It has two important roles.  The first role is to insulate and protect the nerve cells (called axons). The second role is to allow electrical impulses to transmit quickly and efficiently along the nerve cells. The ability to transmit electrical impulses efficiently helps you move around effortlessly and react quickly when needed. The immune attack on the fatty myelin sheath leaves the nerve cells exposed and vulnerable. In some cases the actual nerves are also destroyed. There is also a great deal of inflammation (swelling) that occurs with this process so MS is also described as inflammatory as well as autoimmune.

The damage to the nerves from the attack and inflammation creates varying levels of disruption in the communication process.  Some communication signals within the CNS become slower or erratic while in other cases the signals may not be able to get through at all.  With the damage you may not be as quick to move and it may take much more effort than with normal communication signals.

Axons (nerve cells) As your review the picture notice that  on the left, the nerve cell is well protected by myelin covering.  On the right, the myelin has been damaged.


Analogy:  Let’s say you buy a new lamp and prepare to plug it in.  You inspect the electric cord to make sure the cord is intact and there is no obvious damage, cuts or tears. The electric cord has many small electric wires that are covered and protected by a rubber covering.  Consider the electric wires as representing our nerves and the rubber covering representing the myelin sheath.  One end of the cord has the electric plug you place in the wall socket and the other end is connected to the lamp.  When you plug the lamp in it lights up. Simple enough, right?

Now, what if something comes along (maybe a mouse or your family pet) and chews away at the protective covering of the electric cord.  As the protective covering is damaged, the electric wires become exposed and may even be destroyed in the attack.

Eventually, you may see changes in the function of your lamp, such as light dimming, flickering, or at times the light does not come on at all.  You may even receive a shock when you plug in the lamp or it is turned on.  Over time, with continued damage to the protective covering, and to the actual wires, the lamp shorts out and no longer works at all.  Although parts of the lamp may be fine and you may have even put in a new light bulb, with the disruption in signals you no longer have a functioning lamp.

This is similar to how the immune system attacks the protective myelin sheath leaving the nerves of the brain and the spinal cord exposed and damaged.  Communications throughout the body from these sites may be slowed, interrupted or stopped completely due to the damage.

This is an important concept to understand in MS.  Although the nerves in your brain and spinal cord may be damaged, the areas that they control may be fine.  This can be very confusing since many of the symptoms experienced are often in different parts of the body.  Often people experience pain, numbness, and strange sensations in their arms or legs but the actual damage has occurred in the brain and/or spinal cord.

As an example, let’s take a look at the eyes (pun intended): the protective myelin sheath of nerves that support your vision (optic nerves) may come under attack by the immune system with MS.  You may experience changes in vision, such as blurriness or double vision.  Sometimes you may even notice an aching pain in your eyes. These symptoms may come and go every now and then, stay for long periods of time, or sometimes become permanent and the vision does not return to normal.

As with the example of the lamp, the damage to the myelin sheath and possibly to the nerves themselves impairs the communications with the brain. Your eyes themselves may be working fine; it is the nerves connecting the eyes to the brain receptors or the actual receptors that have been damaged during the MS attack.

Current research also shows that in addition to the inflammation that occurs with MS attacks, there a process of neuro-degeneration (slow destruction of the nerves) that occurs in MS.  These studies are on going and perhaps we will have more clarity on what came first (the chicken or the egg) in regards to destruction from MS versus inflammation from an attack.


The symptoms people experience, as well as the severity of those symptoms, are different for each person affected by MS. Damage can occur anywhere in the CNS (brain/spinal cord) or optic nerves. Symptoms experienced are based on the location of the immune attack and the extent of damage that has occurred to the myelin sheath and the nerves. In MS it is considered normal for symptoms to come and go due to the damaged areas having communication problems.  Of course if you are experiencing the strange symptoms it feels anything but normal!

Below is a list of symptoms that are associated with MS.  Most people have their own unique set of symptoms and this list may change over time.

MS symptoms that often occur in greater than 50% of people: 

Fatigue, numbness / tingling, vision problems, weakness, walking difficulties, sexual dysfunction, dizziness, vertigo, pain, spasticity, bladder & bowel dysfunction, emotional changes, cognitive & memory changes and depression.

Less common & unusual symptoms occur less often in MS:

Speech problems, swallowing problems, tremors, L’hermitte’s sign, breathing problems, itching, headache, hearing loss, trigeminal neuralgia, eye pain, difficulty swallowing or talking, seizures, episodic outbursts of laughter or crying, vertigo, speech disorders and the MS Hug (described as feeling as if someone is holding you tight).

Invisible symptoms of MS are those that may not be directly seen by others but you feel them just the same.  Examples of these symptoms include the person’s experience of pain or numbness in the body, extreme fatigue, L’hermitte’s sign and others that may not be obvious to people looking at you.  Those close to someone experiencing invisible symptoms see the person as appearing to be perfectly fine.  In reality, some of these invisible symptoms are the greatest cause of suffering and may be severe enough to lead to early disability in people who experience them.

MS Phenotypes

The Different Types of MS (Phenotypes)

For the purposes of scientific study and research, it is important to standardize the descriptions of MS to make sure everyone is “on the same page” when diagnosing and describing MS.  This is especially important when entering people with MS into clinical research studies or offering medications to treat MS.  Prior to 2013, there were a variety of descriptions offered that led to confusion when discussing and researching or offering treatments for MS.  Some of the previous terms are no longer used and most MS experts agree with the current 2013 descriptions.

In 2013 an International Advisory Committee on Clinical Trials of MS agreed upon the following subtypes (also referred to as phenotypes) of MS: 

Relapsing Remitting (RR) is the most common type of MS and occurs in 85-90% of people newly diagnosed with MS. It is characterized by clearly defined relapses (attacks) of worsening neurologic function (or increased symptoms) followed by partial or complete remission (recovery).  When symptoms persist after recovery from the attack, they are referred to as residual symptoms. It is important to remember that the word remission refers only to recovery from the attack and not the ending of the underlying disease.

Secondary Progressive (SP) Most specialists describe this as a phase or course of the disease. Although there are occasional periods of stability and occasional relapses (attacks), they are fewer and recovery from the attack is often incomplete in SP MS. Many people who start with RR MS may move into SP MS as time goes along. It is uncertain as to when this transition happens. In SP, the MS worsens over time and disability may increase for the person with SP MS. 

Primary Progressive (PP) is the least common type of MS occurring in approximately 10% of people diagnosed with MS. It is characterized by a slow decline in neurologic function from the start. This decline is accompanied by a progressive increase of disability without identifiable relapses (attacks) or remissions (recovery from attacks). 

Two additional syndromes approved by the committee to describe MS:

* Clinically Isolated Syndrome (CIS) describes the first clinical presentation of MS symptoms that may or may not be accompanied by MRI changes.  CIS is now recognized as the first clinical presentation of MS but does not fulfill criteria for a MS diagnosis. Current expert recommendations support beginning MS treatment when individuals present with CIS.  The treatments have shown to delay the time to a diagnosis of full MS.

* Radiologically Isolated Syndrome (RIS) describes findings on a MRI that suggest MS although there may not be any clinical signs or symptoms of MS. For example, when a person has a MRI after a head injury unrelated to MS. These changes are considered an incidental (random) finding on an MRI scan.  Uncertainty exists regarding MS treatment for RIS and more studies are in progress to answer this question.

Other terms used in describing MS:

Benign and malignant MS are no longer considered phenotypes per se, but rather provide an indication of disease severity over time. The committee suggested that these terms be used with caution when describing any approved phenotype of MS retrospectively (looking back over time). This means that as the MS Specialist monitors a person’s disease course over time he or she may describe it as benign or malignant. At this time, no one can predict the future of how MS will or will not advance early in the course of the disease.


Cause of MS

Although the exact cause of MS remains a mystery, scientists believe it is likely a combination of genes and an environmental trigger that sets off the immune attack on the myelin.  It remains uncertain as to what this trigger is.  It is also uncertain why some people’s immune systems react and begin an attack on the self while other people’s immune systems do not react. Science has identified that some people have a gene that makes them more at risk for MS, but their immune systems do not always get triggered to begin the attack process.

Risk factors that have been identified include low levels of vitamin D, smoking, and a possible relationship with exposures to certain infections such as Epstein-Barr virus (EBV) or mononucleosis.  Those who have thyroid disease, type 1 diabetes or inflammatory bowel disease also have a higher risk of developing MS.

Having a family member with MS continues to be a risk factor for developing MS.  A specific gene has been linked to the risk of developing MS and is being investigated further.  Although there is a slight increase in developing MS when siblings and parents also have the condition, it is not high enough to say that you are at “high risk” just because a family member has MS.  There are also many who develop MS when there is no history in any other family members or in the extended family for generations. 

Other related factors:  Women are more than twice as likely as men to develop MS. White/Caucasian people are at higher risk for MS.  People with a Northern European descent or those who live in countries with temperate climates (Canada, Northern US, New Zealand, southeastern Australia and Europe) have higher rates of MS. People of Asian, African or Native American descent have a lower risk of developing MS although it does occur. 

Treatment of MS

Although there is no cure for MS at this time, there are treatment options that have demonstrated various levels of effectiveness in reducing relapse rates, slowing the progression of the disease and of disability, and are effective in treating MS attacks.

MS Treatments have three major goals:

Goal #1:  Modify the disease course by reducing the number and severity of relapses, reducing new lesions on the MRI and slowing the progression of disability.

Goal #2: Treat MS attacks as needed (to reduce inflammation)

Goal #3: Manage the symptoms of MS

Goal #1: 

To modify the disease course, current evidence strongly recommends early treatment of MS! 

Many scientific studies have suggested that the most destructive changes in the brain from MS occur early in the disease process.  In some cases, MRI studies indicate that there may be damage before the first symptoms even begin to surface. 

Food and Drug Administration (FDA) approved medications, often classified as disease modifying and/or immunosuppressive, are recommended to treat MS.  Most of these medications will be taken on a long-term basis and have been shown at differing levels to help reduce disease activity through reductions in relapse rates, disease progression and disability in RR MS.  There are some approved for SP MS but the majority are directed at RR MS.

It is not the intent of Your MS Compass to offer recommendations for treatment choice. MS Specialists consider a variety of factors when making recommendations about starting or changing a medication. Some of these medications carry higher risks and require regular testing (blood tests, diagnostic evaluations) to ensure serious (sometimes fatal) potential side effects are identified early.

Since RR MS is the most common form of MS and appears to respond best to treatment, most clinical studies for potential treatments are completed on people with this type of MS.  This is very frustrating to those with progressive forms of MS since most therapies are FDA approved only for RR MS.  In recent years, more studies are directed at finding better options for those with progressive forms of MS.  Be patient, they are coming!

The message here is not to take this decision on choosing a medicine lightly and to be in the know when you make the choice and be sure to follow up for testing / evaluations as recommended.

Goal #2: 

For treatment of MS attacks, most MS Specialists offer high-dose corticosteroid medications.  These steroid medications are typically offered intravenously (IV – through a vein) and given for 3-5 days.  The IV steroids have been successful at reducing the length and severity of the MS attack.  In some practices, the steroids are offered in the oral form (pills).  Other medications/treatments used for MS attacks show varying degrees of success.  Injections of the medication adrenocorticotropic hormone (ACTH) are also used for treating MS attacks and have shown success.  There are reports of MS Specialists successfully treating MS attacks with IV infusions of Immunoglobulin (IVIG) and a more invasive treatment, plasmapharesis (plasma exchange or PLEX). 

Goal #3: 

To manage the symptoms of MS, the most effective treatments involve a combination of medication and lifestyle changes.  For example, when treating the often-disabling symptom of fatigue, both medication and life style changes are recommended.  Lifestyle behaviors may include improving poor sleep patterns, treating depression, increasing physical activity, etc., all of which may improve the fatigue.  With MS, this combination tends to work best.  If you take medication for fatigue but the other factors are not addressed, the results are not as good.  As an analogy, consider that if a person diagnosed with diabetes takes insulin but does not change their diet to reduce eating high levels of sugars and carbohydrates, the results achieved may not be what the person desired.  The same principle of combining medications with lifestyle changes applies to treating symptoms of MS.

Other Concepts of Interest

Scientific evidence now shows healing and/or remyelination of the nerves that have been damaged can also occur in MS.  There are many studies underway to determine how to promote this type of healing and remyelination of nerves. 

The concept of neuroplasticity has received a lot of attention over the years and is worth exploring.  This concept is sometimes known as rewiring of the brain. There are multiple scientific studies and case reports of this rewiring of the brain occurring in other diseases and injury states. Neuroplasticity has been studied a great deal in victims of stroke and people who have sustained other injuries to the brain. The studies demonstrate that the brain can actually reroute (redirect) nerve signals away from damaged areas.  This involves creating new pathways through the healthy areas of the brain to restore function.  There are studies now underway to apply this concept to MS specifically.


It is the goal of Your MS Compass to point you in the right direction to obtain quality scientific information in an effort to guide you in making informed decisions about your treatment, symptom management and life with MS.  With quality information, you can then choose your unique path to manage your MS.

* In addition to the below references, the national MS organizations have recommendations for further readings of approved and scientifically based materials. Check out our RESOURCE page to learn more.

Costello, K, Thrower, B & Giesser, B.  Navigating Life with Multiple Sclerosis. Oxford University Press. American Academy of Neurology 2015.

Campbell, JD, Ghushchyan, V, & McQueen, RB (et. al.).  Burden of Multiple Sclerosis on Direct, Indirect costs and Quality of Life: National US Estimates. Mult Scler Relat Disord. (2014); 3:227-236.

Doidge, Norman (2007).  The Brain that Changes Itself. Penguin Books Ltd, Viking Penguin, a member of the Penguin Group (USA).

Kalb, Rosalind, Giesser, Barbara & Costello Kathleen (authors). Multiple Sclerosis for Dummies (2012).  Wiley (publisher).

Elovaara, I, Kuusisto, H, Wu,X, Rinta, S, Dastidar, P & Reipert, B. Intravenous immunoglobulins are a therapeutic option in the treatment of multiple sclerosis relapse. (2011) Mar-Apr; 34(2): 84-89. PMID: 21301327

Kalb, Rosalind (author) Multiple Sclerosis, 5th Ed.: The Questions you Have – The Answers You Need.  ReadHowYouWant, LLC (publisher).

Markowitz, ED.  Multiple Sclerosis Update. Am J Manag Care (2013)) Nov; 19(16 Suppl): s294-300.  PMID 24494618

Schapiro, Randall (author). Managing the Symptoms of Multiple Sclerosis 6th Edition (2014).  Demos Medical Publishing, LLC.

T. Jock Murray, MD, Carol Saunders, and Nancy Holland (authors).  Multiple Sclerosis: A Guide for the Newly Diagnosed (2012). Springer Publishing Co., Inc.    

Tomassini, V, Mathews, PM, Thompson, AJ, Fuglo, D., Geurts, JJ, Johansen-Berg, H, Jones, DK, Rocca, MA, Wise, RG, Barkhof, F, & Palace, J.  Neuroplasticity and functional recovery in multiple sclerosis.  Nat Rev Neurol (2012) Nov. 5.  8(11): 635-46). Pubmed 22986429