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Multiple Sclerosis (MS)

  • A disease that causes damage to the central nervous system that can ultimately lead to paralysis
  • Symptoms include numbness in extremities, vision problems, and vertigo
  • Treatment to manage symptoms includes medications and corticosteroids
  • Involves neurology

Multiple Sclerosis (MS)


Multiple sclerosis (MS) is estimated to affect almost 1 million Americans and the disease actually comes in many different forms. No two cases of MS, a disease that affects the central nervous system, are the same since nerves are affected in different ways and show a variety of symptoms.

Contrary to some popular perception, MS is not always an unrelenting downward spiral. Indeed the disease has an unpredictable progression (some patients will gradually lose the ability to walk, while other patients will have flare-ups of the disease followed by periods of remission).

For years, its root causes were completely unknown. But researchers—including neurologist David Hafler, MD, who directs the Yale Medicine Neurology Department—have begun to identify the genetic and environmental factors that contribute to the development and progression of MS. Their groundbreaking discoveries help patients to manage the condition and live full and healthy lives never before thought possible.

What causes multiple sclerosis?

In patients with multiple sclerosis, the white blood cells of the body, usually responsible for fighting disease, begin to attack the protective coating, or myelin sheath, around the nerves. Ultimately the nerves begin to break down until the brain and spinal cord are no longer able to effectively communicate with the body.

What are the most common types of multiple sclerosis?

Primary progressive accounts for a small percentage of cases. Usually a patient is 40 years old or older when the ailment is diagnosed, primary progressive patients do not suffer from disease “attacks” the way relapse remitting patients do, but instead tend to gradually lose functionality, becoming increasingly less able. Men and women are equally likely to suffer from primary progressive MS.

Secondary progressive MS usually develops in a relapse remitting MS patient after he has had the disease for 10 to 20 years. As is the case with primary progressive MS, symptoms will continue to worsen and the patient’s mobility will gradually diminish. This is the most difficult type of MS for doctors to treat.

Relapse remitting is the most common type of MS. A patient with relapse remitting MS may experience symptoms intermittently but then improve on her own or with some treatment. For example, a patient might lose vision in one eye for 90 days, recover, and return to normal for a period of time. This type of MS is more common in women.

What are the symptoms of multiple sclerosis?

Because MS progresses differently in all patients, it’s difficult to pinpoint specific early symptoms. But there are a few common conditions that that may lead a physician to investigate possible MS. These include:

  • Numbness or tingling in the extremities. This can be an early sign of possible nerve damage caused by MS.
  • Vision problems. Many patients will see their doctor after experiencing blurry sight or pain that accompanies eye movement. This is often a first symptom that the optic nerve is being affected by MS.
  • Vertigo or difficulty balancing. It’s not uncommon for patients ultimately diagnosed with MS to complain of dizziness, or to describe feeling like the room is spinning.

Less-common symptoms include:

  • Difficulty speaking
  • Difficulty swallowing
  • Seizures
  • Hearing Loss

How is multiple sclerosis diagnosed?

If a patient sees his or her doctor and has any of the more-common symptoms of MS, the doctor may first choose to conduct a magnetic resonance imaging (MRI) scan. This scan will be able to show the doctor whether the patient’s nerve cells have any lesions, indicating areas where the outer layer of the myelin sheath has been eroded. Depending on the MRI scan used, the affected areas will be either lit up or extremely dark.

While an MRI can be a powerful tool for diagnosing MS, a small percentage of patients with the condition will not have any visible lesions. In those cases—or when a doctor otherwise wants to be completely sure of the diagnosis—the physician will order a spinal tap to test the patient’s cerebrospinal fluid, which surrounds the brain and the spinal cord. In patients with MS, this fluid contains higher than normal levels of specific antibodies and proteins (referred to as biomarkers) and the breakdown components of myelin.

A spinal tap is conducted by turning the patient on his side or in a seated position and injecting a local anesthetic. When the area of the patient’s back is numb, the doctor will insert a long hollow needle into the spinal canal and withdraw 1 to 2 tablespoons of cerebrospinal fluid. While a spinal tap can be an uncomfortable procedure, it is very safe and will help doctors arrive at an accurate diagnosis.

What are the risk factors for MS?

While the cause of MS is still unknown, the latest research indicates that the disease may develop when specific genetic mutations are set off by environmental factors. “It’s not a case of bad genes or bad environment,” Dr. Hafler says. “It’s a bad interaction between genes and environment.”

Research has determined that if a patient’s mother or father had MS, she has a higher risk of developing it. In the Hafler Lab at Yale Medicine, Dr. Hafler and his team of researchers have made a major breakthrough in identifying the genetic roots of multiple sclerosis, including more than 150 genetic variants common in people with MS. 

While the genetic variants may be low-risk individually, the team is studying how they interact with one another and how, when combined with specific environmental factors, they cause MS. Some additional environmental factors seem to include:

Diet. An unhealthy diet that is high in salt and fat is believed to create inflammation throughout the body, which is a risk factor for developing MS.

Smoking. Smoking is linked to significantly higher rates of developing MS. For heavy smokers (more than 4 packs a day), the risk of developing MS is five times that of a nonsmoker. For patients who already have relapse-remitting MS, smoking more than 10 cigarettes a day is linked to a greater risk of progressing to secondary progressive MS.

What are the treatment options for MS?

There is still no cure for MS, but there is considerable hope: “Thirty years ago, when I told a patient they had MS, I said, ‘I’ll be here for you,” says Dr. Hafler. “Today it’s a different story. I tell them this is a very treatable disease.”

As research indicates that some of the greatest brain damage may occur in the early stages of MS, the philosophy of treatment at Yale Medicine is to begin early and aggressively in hopes of preventing any progression. A range of available therapies may be tried—and cycled through—as a doctor determines what will be most effective and cause the fewest side effects. Treatment plans vary, based on an individual patient’s needs, but several oral medications, intravenous infusions, and injections can stop the disease from developing further.

Some of the most common oral medications include Aubagio, Gilenya, and Tecfidera. All have specific strengths and side-effects; a patient’s physician will sometimes have to try different combinations to determine what is providing the right amount of treatment with the most tolerable amount of side effects. (Gilenya, for example, can cause a slow heart rate immediately after being taken, so patients taking the drug for the first time are advised to do so under doctor’s supervision.) 

Many of the drugs also can compromise the patient's immune system, causing her to be more susceptible to viruses and infections.

Intravenous infusions and injections include:

  • Betaseron, a daily injection
  • Avonex, intramuscular injections performed weekly
  • Rebif, a subcutaneous injection given three times a week
  • Copaxone, a daily subcutaneous injection
  • Tysabri, an intravenous infusion given once a month
  • Novantrone, an intravenous infusion given once every 3 months, for 2 to 3 years
  • Rebif, Avonex, Betaseron and Extavia are known to sometimes cause flu-like symptoms after injections. A doctor may often gradually increase a patient’s dosage so that the side-effects are minimal.

For patients suffering from acute MS flare-ups caused by relapse-remitting MS, a common treatment is to inject corticosteroids—a synthetic adrenal steroid—to reduce inflammation in the body and relieve symptoms, which can vary from fatigue and stiff muscles to difficulty walking and problems with cognition.

Changes to improve a patient’s overall wellness—including prioritizing proper rest, stress reduction, regular exercise, and a balanced, nutrient-rich diet—have also been shown to alleviate symptoms.

What makes Yale's approach to treating MS unique?

At Yale Medicine, patients aren’t just in the hands of skilled and compassionate physicians. They are also being treated by the world’s leading MS researchers, who have dedicated their careers to finding the causes and effective treatments for the disease.

“When a patient’s facing an MS diagnosis, I want them to know that we’ll be there for them,” says Dr. Hafler. “I give all my patients my home phone numbers. The most important message is that someone is there to care for them.”