The number of people who have
multiple sclerosis (MS) increases the farther away
they are from the equator.
In areas near the equator, MS occurs in fewer than 1 out of 100,000 people. In areas
farther from the equator—such as northern Europe and northern North America—MS
occurs in around 30 to 80 out of 100,000 people.1 When moving south of the equator, the number of people
with MS is less dramatic, but the same trend is seen.
Some evidence suggests that people who move from a high-risk to a
low-risk area before the age of 15 reduce their chances of developing MS.
But the same is true in reverse. In those who move from a low-risk area to
a high-risk area before the age of 15, the risk of getting MS increases. Those
older than 15 when they move to a new area retain the risk associated with
their old area.1
Most experts agree that this unusual relationship between geographic
location and MS suggests that an environmental factor is partly responsible for
causing the disease.
Ropper AH, Samuels MA (2009). Multiple sclerosis and
allied demyelinative diseases. In Adams and Victor's Principles of Neurology, 9th ed., pp. 874–903. New York:
February 15, 2012
Adam Husney, MD - Family Medicine
& Anne C. Poinier, MD - Internal Medicine & Barrie J. Hurwitz, MD - Neurology
How this information was developed to help you make better health decisions.
To learn more visit Healthwise.org
© 1995-2013 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
We are happy to take your appointment request over the phone, or, you may fill out an online request form.
Disclaimer: The information on this website is for general informational purposes only and SHOULD NOT be relied upon as a substitute for sound professional medical advice, evaluation or care from your physician or other qualified health care provider.