Multiple Sclerosis (MS)

Multiple sclerosis (MS) is a disease of the brain, spinal cord, and optic nerves that can cause problems with muscle control and strength, vision, balance, sensation (such as numbness or tingling in your feet or hands), and mental functions such as thinking (cognition) and moods.

The symptoms of MS are caused by inflammation of the central nervous system and the destruction of, the protein coating that surrounds and protects nerve fibers (axons). The process of myelin destruction is called demyelination. The resulting damage disrupts the normal flow of nerve impulses through the brain, spinal cord, and nerves, which make up the central nervous system. Lesions, or plaques, form in areas of demyelination. In many cases the cells that create myelin (oligodendrocytes) are destroyed, as are the nerve fibers (axons), contributing further to disability.

In most areas of the United States, multiple sclerosis affects an estimated 250,000 to 350,000 people, or about 1 in 1,000. About two-thirds of the people who have MS are women.

Multiple sclerosis occurs most often in young and middle-aged adults; about two-thirds of MS cases begin between ages 20 and 40, with the risk peaking at age 30. The disease is rare in children and in adults older than 60.