What Is Multiple Sclerosis?

Your brain, spinal cord, and optic nerve make up your central nervous system (CNS), which controls many important functions in your body. Your CNS controls thought process, records senses, and guides movement, among other tasks.

The neurological disease multiple sclerosis (MS) can cause problems with your nervous system. MS interferes with the signals that the brain and spinal cord send between each other and other parts of your body. MS damage is due to an unwanted attack by the person’s own immune system on the myelin, which is the insulating layer around brain and spinal cord nerves. People with MS may experience problems with vision, strength, sensation, balance and coordination, thinking, mood, and other problems.

“MS is a very variable disease,” says Rock Heyman, MD, associate professor and chief of the Division of Neuroimmunology and MS in the Department of Neurology at University of Pittsburgh’s School of Medicine. “There are different clinical types of MS. There are a few people who have MS where it is mild and does not lead to disability at all. Unfortunately, MS usually causes disability; however, the risk of and severity of disability can be greatly diminished with treatment.”

About 1 million people in the United States have MS, according to a study by the National MS Society. Worldwide, 2.3 million people have it.

Types of Multiple Sclerosis

There are four basic “types” of MS, broken down by the typical way the disease begins and progresses:

  • Clinically Isolated Syndrome (CIS): An episode of at least 24 hours in which you experience neurological symptoms that are similar to MS. If you have an episode of CIS, you may or may not develop full blown MS in the future. You should be monitored by a neurologist for future episodes.
  • Relapsing-remitting MS (RRMS): The most common way MS begins. Your MS will flare up with new or worse symptoms which may improve (remit) either partially or seemingly completely. At this stage of MS, the disease itself does not get worse between flare-ups. You usually should be on a treatment at this time to decrease both relapses and the risk of developing disability.
  • Secondary progressive MS (SPMS): This type of MS often develops after RRMS, especially if the disease has not been controlled with treatment. During SPMS, you may still have exacerbations. However, your level of disability can increase even without exacerbations. This stage of disease may benefit from treatment to decrease exacerbations and slow disability progression.
  • Primary progressive MS (PPMS): In this form, you experience disability progression from the disease’s onset. There are few, if any, remissions. Your disease usually gets worse. However, this also may benefit from treatment.

Never Miss a Beat!

Get Healthy Tips Sent to Your Phone!

Message and data rates may apply. Text the word STOP to opt out and HELP for help. Click here to view the privacy and terms.

What Causes Multiple Sclerosis?

Scientists do not know the exact cause of multiple sclerosis. Both genetic (inherited) and environmental factors exist.

Several characteristics could increase your chances of getting MS. Those risk factors include:

  • Genetics: Having a first-degree relative (mother, father, sibling, or child) with MS can increase your risk by about 40 times the average rate, Dr. Heyman says.
  • Gender: Women are three times more at risk of MS than men.
  • Age: Although anyone can get MS, diagnosis usually happens between the ages of 20 and 50.
  • Vitamin D: Low levels of vitamin D in your blood can put you at greater risk.
  • Smoking: Smoking can put you at higher risk of getting MS, and the disease is often more disabling in smokers.
  • Obesity: Studies have linked obesity during adolescence with the development of MS.
  • Location: Multiple sclerosis is more common farther from the equator.
  • Viruses: Studies have looked for links between MS and many different infections.  Data suggests that having infection with the Epstein-Barr virus (which causes mononucleosis) as a teenager increases this risk. The vast majority of people who have this infection do not get MS, however.

Dr. Heyman says lowering your risk factors – such as stopping smoking or taking vitamin D – may help prevent MS.

Multiple Sclerosis Symptoms

Symptoms of MS vary by person and can come and go depending on the progression of the disease. Common symptoms include:

  • Vision problems, including vision loss or blurring, or double vision
  • Numbness or tingling feeling
  • Weakness
  • Balance/coordination problems, tremors, or decreased dexterity
  • Fatigue
  • Pain
  • Depression and/or anxiety
  • Impaired cognitive function
  • Spasms/stiffness
  • Bladder and bowel control problems
  • Sexual dysfunction

Diagnosis of Multiple Sclerosis

Diagnosing MS can be difficult. The disease has many different symptoms that can come and go, and it can affect people in many ways. In some cases, doctors can diagnose MS quickly. In others, the process can take longer.

Also, no specific test can diagnose MS on its own. Instead, doctors can use a combination of diagnostic methods, including:

  • Medical history: Doctors will take your medical history, including symptoms, family history, and other illnesses.
  • Neurological exam: These exams can test your central nervous system, analyzing your vision, strength, reflexes, coordination, walking, and balance.
  • Blood tests: Doctors can test your blood for other conditions that cause similar symptoms to MS, potentially ruling them out.
  • MRI: This type of scan can show lesions on your brain and/or spinal cord.  It is much better than CAT scans for detecting MS and may help differentiate MS from another condition.
  • Lumbar puncture: Also known as a spinal tap, this procedure takes a small amount of fluid from your spine. MS usually causes increased amounts of antibodies in the spinal fluid. Dr. Heyman says this test is not needed in every patient.

Dr. Heyman says other conditions, such as carpal tunnel syndrome or pinched nerves by a spinal disc, may mimic MS in some ways. The complexity of the nervous system may make an MS diagnosis even more difficult, especially for a physician who is not a neurologist.

“It can be a difficult diagnosis, but it’s much better in this day and age than it was 40 years ago because the availability of MRI scanning gives so much more information,” Dr. Heyman says. “But it still requires a clinician who knows about MS. Even though the MRI might look like MS and the symptoms might look like MS, there are many other things that can be mimics.

“If you want to have a good outcome, it’s all the more important you have a correct diagnosis and you and your neurologist are sure it’s MS and not something else.”

Treating Multiple Sclerosis

There is no cure for MS. However, many different treatments exist for the disease.


Doctors can prescribe many different types of medications.

  • Injectable medications: These include several different varieties of interferon beta injections, along with glatiramer acetate. These medications can modify the immune system to control attacks and do not appear to increase infection risks. They have different types of side effects and are considered to have a more modest potency compared to the oral and infusion agents.
  • Oral medications: These are considered stronger than the injectable medications. Different medications in this group carry their own benefits and side effects. These can suppress the immune system, making a person more at risk for infection or other problems.
  • Infused medications: Given intravenously (through an IV), these are considered more potent that some of the other agents. They also can suppress the immune system and require visits to an infusion center to receive them.

“You want to balance,” Dr. Heyman says. “Many factors come in to play with treatment decisions.  The predicted severity of the disease, other medical conditions the patient may have, desires for pregnancy, tolerance of the patient for risk. The goal is that a treatment be tolerable (in terms of side effects and finances), effective, and interferes as little as possible with life.”

Lifestyle changes

Dr. Heyman recommends people with MS learn as much about it as they can from sources like the National Multiple Sclerosis Society.

There are ways people with MS can manage the condition and its symptoms on their own.

  • Exercise: A regular exercise program can help moderate the progression of MS. It can promote strength, bone density, and an improved quality of life, Dr. Heyman says.
  • Vitamin D: Taking supplements of vitamin D may help cut down on MS activity, Dr. Heyman says.
  • Quitting smoking: Quitting smoking may slow the disease progression.
  • Maintaining mental health: People with MS can develop depression and anxiety. Treatments for mood problems can be very beneficial.
  • A strong support system: This can help overall quality of life.
  • Diet: A healthy diet can help people living with MS and avoid complications that may make good health more difficult to maintain.

Dr. Heyman says combining lifestyle changes with the right medication can improve the prognosis of someone living with MS.

Multiple Sclerosis. American Academy of Family Physicians. Common Questions. Multiple Sclerosis Foundation. Myelin. U.S. National Library of Medicine.

About Neurosurgery

The UPMC Department of Neurosurgery is the largest academic neurosurgical provider in the United States. We treat conditions of the brain, skull base, spine, and nerves, including the most complex disorders. We perform more than 11,000 procedures each year, making our team one of the most experienced in the world. Whether your condition requires surgery or not, we strive to provide the most advanced, complete care possible. Our surgeons are developing new techniques and tools, including minimally invasive treatments. Find an expert near you.