Multiple Sclerosis, or MS, is a disease in which the immune system abnormally attacks the central nervous system (the brain, spinal cord and optic nerve). It damages nerves and myelin, the fatty substance that protects nerve fibers, distorting or interrupting nerve impulses and causing irreparable damage. Scars (sclerosis) form on the damaged myelin, thus the name of the disease.

Who Does It Affect?

Women are 2 to 3 times more likely to develop MS than men are. Most patients are diagnosed between ages 20 and 50, although it can strike individuals older or younger.

Caucasians, particularly those of northern European decent are more at risk. The incidence of MS increases as you move away from the equator, leading health experts to speculate that sunshine and vitamin D may play an important role in MS. Residents of Sweden and Argentina, both farthest from the equator in their respective regions, have higher incidences of MS, while residents of sub-Saharan Africa, which is close to the equator, has far fewer cases. Worldwide, about 2.3 million people are living with MS.

What Are the Symptoms?

The symptoms of MS vary and can come and go (or be long lasting), making it difficult to diagnose. The most common symptoms include: fatigue; numbness; balance and coordination problems; bladder, bowel, visual, cognitive, or sexual dysfunction; emotional changes; depression; and spasticity. Less common symptoms include: headache, hearing loss, seizures, itching, and difficulty with speech, swallowing, or breathing.

Most MS patients (85 percent) have relapsing-remitting MS, characterized by clearly defined attacks followed by periods of remission.

What Are the Causes?

Physicians are not entirely sure, although they believe one or more environmental factors may trigger MS in susceptible individuals. Having a first degree relative with MS increases your risk, although most MS patients do not have a relative with the disease.

How Do You Treat MS?

So far, there is no cure for MS; however, it's rarely life threatening. Disease-modifying agents may reduce MS activity and disease progression. Many patients find physical or occupational rehabilitation helps them improve or maintain their ability to perform safely and effectively. According to the MS Society, the majority of MS patients do not become severely disabled and two-thirds remain able to walk independently or with an aid.

Are There Any Noteworthy Advances in Understanding MS?

Studies are increasingly demonstrating that vitamin D levels, which are low in a large percentage of the worldwide population, have a significant impact on the course and progression of MS, which may lead to opportunities to prevent and treat the disease.

Rafael Pajaro, MD, reviewed this article.



National Multiple Sclerosis Society. "What is Multiple Sclerosis?" accessed 10 October 2013.

The Mayo Clinic. "Multiple Sclerosis," 15 December 2012; accessed 10 October 2013.

Medline Plus. "Multiple Sclerosis," National Library Medicine, accessed 10 October 2013.

National Institutes of Health. "Multiple Sclerosis," PubMed, accessed 10 October 2013.

Medscape Medical News
Sue Hughes, "More Evidence of Benefit With Vitamin D in MS," 4 October 2013.

Andrew N. Wilner, MD, Fred D. Lublin, MD, and Robert J. Fox, MD, "Three Major Advances in Multiple Sclerosis," 10 October 2013.

"Multiple Sclerosis Cases Hit 2.3 Million Worldwide," 2 October 2013.

Megan Brooks, "Menopause Linked to Worsening Symptoms for Women With MS," 3 October 2013.