The best one-word description for multiple sclerosis (MS) is "unpredictable," according to the June issue of Mayo Clinic Women's HealthSource. MS interferes with the communication between the brain and the rest of the body. Just how that interference plays out in symptoms is different for everyone -- thus, the unpredictable label.
In patients with MS, the immune system attacks the covering (myelin sheath) that surrounds the nerves in the brain and spinal cord. The attacks lead to inflammation and injury to the myelin sheath, which can result in multiple areas of scarring (sclerosis). Eventually, the scarring can slow or block nerve signals that control vision, muscle coordination, strength and sensation.
MS symptoms vary in intensity and duration, and occur in various combinations. Some people experience attacks or flare-ups followed by remissions. Others experience gradual worsening of symptoms. Typically, symptoms first appear between ages 20 and 50. Women are about twice as likely as men to develop MS.
The most common symptoms are abnormal sensory feelings such a numbness, tingling or prickling pain in the lower half or on one side of the body. Many people with MS also experience muscle weakness in one or more limbs and difficulty with coordination and balance. Symptoms may be severe enough to impair walking or standing. Other symptoms can include muscle stiffness and spasms, fatigue, blurred or double vision, difficulty concentrating, depression and loss of bowel and bladder control.
What causes or triggers MS is unclear. There is no cure for MS, but a number of therapies can treat symptoms or reduce the duration or severity of flare-ups. Other treatments, some still being studied, may help slow the course of the disease. Treatment options include:
Corticosteroids: These anti-inflammatory drugs can shorten and reduce the severity of acute attacks.
Interferons: These drugs -- including Betaseron, Avonex and Rebif -- are genetically engineered copies of antiviral proteins that occur naturally in the body. They have been shown to decrease the number of attacks and may decrease the destruction of myelin, possibly slowing progression of MS.
Glatiramer (Copaxone): An alternative to interferons, it is believed to help curb MS attacks by blocking the immune system's attack on myelin.
Natalizumab (Tysabri): This drug can reduce the frequency of MS attacks by limiting the ability of immune cells to move from the bloodstream to the brain. However, it can increase the risk of serious brain infection.
Mitoxantrone (Novantrone): Clinical trials show that this immunosuppressant drug may help slow down MS. It may not be effective unless there's evidence of active inflammation. The drug has been associated with serious side effects such as heart problems and leukemia.
Symptom-specific medications: A number of drugs can help relieve symptoms such as muscle stiffening, fatigue, depression and incontinence. Recently, the Food and Drug Administration approved the drug dalfampridine (Ampyra) as a treatment to improve walking in adults with MS.
In addition to medications, patients with MS may benefit from counseling, physical therapy and lifestyle modifications to help manage symptoms.