Multiple sclerosis (MS) is a condition wherein the immune system attacks the myelin sheath (protective cover of the nerve cells), and eventually can cause the nerves to deteriorate or be damaged. Although the exact case is unknown, multiple sclerosis is considered to be an autoimmune disease.
These factors may increase your risk of developing multiple sclerosis:
- Age. MS can occur at any age, but most commonly affects people between the ages of 15 and 60.
- Sex. Women are about twice as likely as men are to develop MS.
- Family history. If one of your parents or siblings has had MS, you are at higher risk of developing the disease.
- Certain infections. A variety of viruses have been linked to MS, including Epstein-Barr, the virus that causes infectious mononucleosis.
- Race. White people, particularly those of Northern European descent, are at highest risk of developing MS. People of Asian, African or Native American descent have the lowest risk.
- Climate. MS is far more common in countries with temperate climates, including Canada, the northern United States, New Zealand, southeastern Australia and Europe.
- Certain autoimmune diseases. You have a slightly higher risk of developing MS if you have thyroid disease, type 1 diabetes or inflammatory bowel disease.
- Smoking. Smokers who experience an initial event of symptoms that may signal MS are more likely than nonsmokers to develop a second event that confirms relapsing-remitting MS.
People with multiple sclerosis also may develop:
- Muscle stiffness or spasms
- Paralysis, typically in the legs
- Problems with bladder, bowel or sexual function
- Mental changes, such as forgetfulness or mood swings