By John Heddle
Canadians, women especially, have one of the world’s highest risks of MS and some think it is increasing. Why? And what is MS?
For an explanation of what MS is and how it is diagnosed, go to the Mayo Clinic’s page.
The actual causes of MS have not been identified definitively nor even the complete pathology of the condition. What seems certain is that the body’s own immune system attacks some of the myelin of the nerves. Myelin is like the insulation on a wire and the nerves are like the wire. Without adequate insulation, nerve messages can be short-circuited, detoured, delayed, or interrupted, thus interfering with the brain’s ability to control muscles. But why is the myelin attacked? This is not known but it is clear that there is an association with a virus called Epstein-Barr. In many other conditions in which the body attacks itself, an infection is a trigger. Such autoimmune conditions can also be triggered by exposures to an external agent, such as something in food, which the immune system reacts to and, in doing so, also reacts to a part of the body which has a similar structure at the molecular level. It seems that such reactions are idiosyncratic, which is to say that they are seemingly unique to the person affected. Women are more likely to be affected by the Epstein-Barr virus which is associated inside cells with the actual sex chromosomes in women. In women, who have two X chromosomes unlike men with one X and one Y, one of the X chromosomes is rendered largely inactive. This is a balancing of the chromosomes so that men and women are alike in the number of functional X’s. Without such a balancing mechanism, there would be genetic chaos of the type which we can see in Down Syndrome in which one extra of the smallest human chromosome causes so many abnormalities. But why this virus is associated with the inactive X is a mystery.
This explains, insofar as it goes, why women are more frequently affected than men. Why, though are Canadians more at risk? Again, the explanation is superficial. It is clear, nevertheless, that people of northern European descent are at greater risk, just not why this should be so. As a large proportion of the Canadian population’s ancestors came from Scotland, England, Ireland, and Scandinavia, this would account for a higher rate of MS.
A study of the rates of MS in Canada shows that the rate of MS is not increasing and that deaths from MS are decreasing among the young. Unfortunately, the death rates among the elderly are increasing in spite of many promising new treatments. One of these is activity, which seems quite effective.
The Multiple Sclerosis Society of Canada has a very good website, https://mssociety.ca/ with a great many pointers to sources of information and help for those affected and their caregivers, including social, legal, and support matters.