Who gets multiple sclerosis?

Approximately 400,000 Americans and millions of people worldwide have MS. 

• The onset of MS typically occurs between the ages of 20-50 years. MS is the most common, disabling neurologic disorder in young adults. 



• Women are about 2 times more likely than men to develop MS.



• The disease is more common in people who live farther from the equator, although the strength of this association has recently been questioned.   



• MS occurs more frequently in whites with northern European ancestry. People living in North America, Europe, and Australia are more likely to develop MS than those living in Asia.  



• Genetic factors play a role in MS. If a parent or a sibling has MS, the risk of developing MS is 3%. If an identical twin has MS, the risk of the other twin is 25-40%. 



• Endocrine factors are also thought to play a role in MS. For instance, there is a decrease in the number of MS attacks during pregnancy. Within the 3 months that follow pregnancy, the chance of new MS attacks is higher. This fluctuation in disease severity is thought to be a response to hormonal changes that occur during the pregnancy and the postpartum period.