Multiple sclerosis (MS) is a disease of the central nervous system, in which the body’s own immune system attacks myelin, the fatty substance that surrounds and protects nerve fibers in the brain, spinal cord and eyes. Damage to myelin creates scar tissue (sclerosis), which interferes with the way nerve signals are transmitted.
Depending on where the damage occurs, symptoms can vary widely and may range from mild to severe.
The types of symptoms, their severity and how the disease progresses can differ greatly from one person to another. Symptoms may include extreme fatigue, tingling, numbness, weakness, difficulty walking, poor coordination, impaired vision, slurred speech, tremors, stiffness and bladder problems. Severe MS may cause blindness, paralysis and confusion.
“Unlike other diseases, MS varies widely in terms of symptoms, aggressiveness, response to treatment and disease burden. This makes treating the disease particularly challenging and underscores the importance of personalized care,” says Timothy West, MD, Director of the Multiple Sclerosis Program at the Lou Ruvo Center for Brain Health in Las Vegas, Nevada.
Unlike most other neurological diseases that affect older people, MS tends to be diagnosed between the ages of 20 and 50. Of the more than 400,000 people in the United States with MS, two-thirds to three-fourths are women. MS is not a fatal disease, but it can be disabling.
There are four types of MS:
Richard Rudick, MD
Dr. Rudick has played key roles in several MS clinical trials, including pivotal registration trials of IFNß-1a (Avonex) and natalizumab (Tysabri) for relapsing-remitting MS.
About 85 percent of patients have this type of MS, which causes disease flares (relapses) followed by periods of partial or total recovery (remission). The majority of approved medications slow (modify) this type of MS.
Approximately 10 percent of patients have this form of MS, which slowly worsens over time. Although the disease may occasionally plateau, remissions do not occur. There are no effective medications for this type of MS, but new medications are being tested in clinical trials.
Some patients with relapsing-remitting MS eventually stop having remissions, and their disease begins to grow steadily worse. New MS medications may prevent this from occurring in many patients.
The small number of patients with this form of MS experience a steady worsening of their disease, punctuated by relapses. Unlike relapsing-remitting MS, their condition continues to decline between relapses.
The Lou Ruvo Center for Brain Health in Las Vegas, Nevada and the Mellen Center, Cleveland Ohio provide comprehensive care for patients with all four types of MS. For more information about MS, please visit clevelandclinic.org/Mellen.