MS, also known as multiple sclerosis, is a disease that affects the transmission of nerve impulses in the central nervous system. It often results in a loss of coordination and muscle control. Approximately 250,000 to 350,000 people in the United States are currently diagnosed with multiple sclerosis.
What Is MS?
Multiple sclerosis, or MS for short, is an unpredictable disease of the central nervous system (the brain and spinal cord) that usually first appears between the ages of 20 and 40. MS affects women twice as often as men, and is the leading cause of disability among young adults.
Although MS was first diagnosed in 1849, the earliest known description of a person with possible MS dates from fourteenth century Holland.
People who have MS may lose coordination and muscle control. However, many people with MS are only mildly affected by the disease and continue to leads their lives much as they did before their diagnosis.
Patterns of MS
There are four main patterns 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 a steady worsening of symptoms from the first sign of illness. This is called primary progressive MS.
The two other main forms of MS include secondary-progressive and progressive-relapsing.
(Click Types of Multiple Sclerosis for more information.)
What Happens During an Attack?
During an MS attack, inflammation occurs in areas of the white matter of the central nervous system in random patches called plaques. This process is followed by destruction of myelin, the fatty covering that insulates nerve cell fibers in the brain and spinal cord. Myelin facilitates the smooth, high-speed transmission of electrochemical messages between the brain, the spinal cord, and the rest of the body. When myelin is damaged, the transmission of messages may be slowed or blocked completely, leading to diminished or lost function.
The name "multiple sclerosis" signifies both the number (multiple) and condition (sclerosis, from the Greek term for scarring or hardening) of the demyelinated areas in the central nervous system.