Who Gets MS?

SOURCE: www.PersonalHealthZone.com and  http://www.msrc.co.uk

Most people experience their first symptoms of MS between the ages of 20 and 40, but a diagnosis is often delayed. This is due to both the transitory nature of the disease and the lack of a specific diagnostic test--specific symptoms and changes in the brain must develop before the diagnosis is confirmed.

Although scientists have documented cases of MS in young children and elderly adults, symptoms rarely begin before age 15 or after age 60. Whites are more than twice as likely as other races to develop MS. In general, women are affected at almost twice the rate of men; however, among patients who develop the symptoms of MS at a later age, the gender ratio is more balanced.

MS is five times more prevalent in temperate climates--such as those found in the northern United States, Canada, and Europe--than in tropical regions. Furthermore, the age of 15 seems to be significant in terms of risk for developing the disease: some studies indicate that a person moving from a high-risk (temperate) to a low-risk (tropical) area before the age of 15 tends to adopt the risk (in this case, low) of the new area and vice versa. Other studies suggest that people moving after age 15 maintain the risk of the area where they grew up.

These findings indicate a strong role for an environmental factor in the cause of MS. It is possible that, at the time of or immediately following puberty, patients acquire an infection with a long latency period. Or, conversely, people in some areas may come in contact with an unknown protective agent during the time before puberty. Other studies suggest that the unknown geographic or climatic element may actually be simply a matter of genetic predilection and reflect racial and ethnic susceptibility factors.

Above is a map giving the geographical prevalence of Multiple Sclerosis (MS) world-wide. It has long been established that MS is more likely to occur in communities in the further Northern and Southern Latitudes, possibly due to less sunlight, environmental factors or dietary reasons.

We report below on news stories and scientific articles from around the world which look into this apparent "geographical phenomenon".

-  It is generally accepted this country has the highest rate in the world and there are an estimated 10,500 people coping with MS in Scotland

-  Across the UK about one in every 800 people has MS.

-  But in Scotland about one person in every 500 has MS.

-  It's far more common here and in countries like Canada, Scandinavia and Ireland than it is in countries nearer the equator.

-  The French West Indies (FWI), i.e., the islands of Martinique and Guadeloupe, have recently experienced the emergence of multiple sclerosis (MS).

- The Palouse area of eastern Washington is one of the nation's hot spots in terms of reported cases of MS.  These hot spots are located all over the country: New York, Missouri, Kansas, and, as it turns out, eastern Washington.

-  Multiple sclerosis (MS) may be 50% more common in the U.S. than previously thought, according to a new research review.

-  In Scotland, there is 137 per cent more MS than in England and Wales. MS is more prevalent in northern Great Britain and northern Ireland than in England and Wales.

Periodically, scientists receive reports of MS "clusters." The most famous of these MS "epidemics" took place in the Faeroe Islands north of Scotland in the years following the arrival of British troops during World War II. Despite intense study of this and other clusters, no direct environmental factor has been identified. Nor has any definitive evidence been found to link daily stress to MS attacks, although there is evidence that the risk of worsening is greater after acute viral illnesses.

Geographic location and multiple sclerosis

SOURCE: www.webmd.com

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 1 in 100,000 people. In areas farther from the equator-such as northern Europe and northern North America-MS occurs in around 30 to 80 of every 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. However, 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.¹ Those older than 15 when they move to a new area retain the risk associated with their old area.

Most experts agree that this unusual relationship between geographic location and MS suggests that an environmental factor is partly responsible for causing the disease.

Citations

1. Ropper AH, Brown RH (2005). Multiple sclerosis and allied demyelinative diseases. In Adams and Victor's Principles of Neurology, 8th ed., pp. 771–796. New York: McGraw-Hill.