Multiple Sclerosis Home > What Is Multiple Sclerosis?
Many people -- especially those who are newly diagnosed or have friends or family members with MS -- wonder, "What is multiple sclerosis?" Simply put, MS is a disease that affects the transmission of nerve impulses throughout the central nervous system. This disease can affect some people only mildly, while it can be disabling to others.
Multiple sclerosis is a disease of the central nervous system (brain and spinal cord) that usually first appears between the ages of 20 and 40, and affects women twice as often as men. Multiple sclerosis (MS) is the leading cause of disability among young adults.
People who have MS may lose coordination and muscle control. However, many people are only mildly affected by the disease and continue to lead their lives much as they did before their diagnosis.
There are four main patterns, or types, of multiple sclerosis. The more common pattern is an episode of symptoms lasting days or weeks followed by a period of no symptoms for weeks or months. This type of multiple sclerosis is called relapsing-remitting MS.
A less common pattern of multiple sclerosis is steady worsening of symptoms from the first sign of illness. This is called primary progressive MS.
The two other main forms of multiple sclerosis include secondary-progressive and progressive-relapsing.
(Click Types of Multiple Sclerosis for more information.)
Symptoms of multiple sclerosis can include:
- Numbness, weakness, tingling, or paralysis in one or more limbs
- Impaired vision and eye pain
- Lack of coordination or unsteady gait
- Rapid involuntary eye movement.
A history of at least two episodes of a cluster of symptoms is necessary for a diagnosis of MS. Because MS affects the central nervous system, symptoms may be misdiagnosed as mental illness at first. Furthermore, because symptoms of MS often mimic other diseases, a misdiagnosis is common.