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Published as a special resource from the Nancy Davis Foundation for MS and WebMD.

What is Multiple Sclerosis?

Multiple sclerosis is a disease of the central nervous system (brain and spinal cord) in which the insulating protective covering (myelin sheath) surrounding the nerves is destroyed or damaged, resulting in interference with the brain’s signals to various parts of the body. Hard or firm scar tissue replaces areas where the myelin has been lost, hence the name multiple sclerosis (multiple scars) in many patients. MS symptoms can be relatively benign in some cases to completely debilitating in other patients, as communication between the brain and other parts of the body is disrupted.

Who contracts MS?

Young adults between the ages of 20 and 40 are most likely to develop MS. The disease is also at least twice as common in women as men, perhaps related to hormonal factors. The incidence of MS is ten times higher for those living in northern countries and the northern United States above the 40th parallel. The rate of MS decreases significantly in populations further south.  Most scientists think the cause of MS is “multifactorial”. The person’s genetic heritage, gender, birthplace, age and environment contribute to susceptibility, resistance, and pattern of the course of MS. It is not an inherited disease, in the strict sense, but certain susceptibility does run in families. One theory suggests a common viral infection in your early teens results in the development of an immune response (autoimmune reaction) when one becomes an adult. In this autoimmune process, immune cells mistake myelin for a foreign invader and attack it.

What are the symptoms of MS?

Multiple sclerosis causes a wide variety of symptoms. The most common symptoms are:

  • Numbness or tingling
  • Unusual fatigue, weakness and exhaustion
  • Vision problems
  • Poor coordination or difficulty walking
  • Slurred speech
  • Bladder problems

No two persons with MS will necessarily display the same symptoms, making it difficult to predict the course of the disease for an individual patient. Symptoms may occur suddenly and remain constant, or may continue in a progressive or episodic pattern. The uncertainty and unpredictability of MS makes living very difficult for the victims, their families and friends.

How is MS diagnosed?

To be accurately diagnosed with MS, your doctor will order a complete set of MRI studies, nerve conduction studies and possibly a spinal tap. From those results the doctor will determine if your symptoms are attributable to MS. Currently there is a blood test being developed that will identify MS, hopefully giving many people a chance at early detection and treatment.

What is the clinical course of MS?

There are several different clinical courses: relapsing-remitting, secondary-progressive, primary-progressive and, rarely, progressive-relapsing. Relapsing-remitting occurs in 85% of newly diagnosed MS patients. Patients will have an attack or relapse, which lasts usually a few weeks, and will have either new symptoms develop, or have symptoms recur or worsen. Patients may return to normal or have permanent remaining symptoms. Secondary-progressive usually develops in about half the patients initially diagnosed with relapsing-remitting MS. In this type the patient slowly and steadily gets worse. There may be an occasional relapse or attack, or perhaps no recurrence of attacks with this type. Primary-progressive MS affects about 15% of all MS patients and the patient worsens steadily without having a relapse or attack. Progressive-relapsing MS is similar to primary-progressive MS in its steady deterioration except that the patient experiences occasional attacks along with the already worsening symptoms.

Nancy Davis Foundation For MS

The foundation is dedicated to the treatment and ultimate cure of MS. Funding research is the core focus of the foundation. Their annual MS Forum & Expo on May 8th featured top MS doctors discussing the latest advances in MS research and patient care.