By John A. Heddle
Canadians, women especially, have the world’s highest rates of MS and some think it is increasing. New cases are not increasing but as people with MS are living longer, the proportion of people with MS is, indeed, increasing. At least 77,000 Canadians are currently known to be affected, 0.2% of the population. Three quarters of these are women. On average, eight women and three men are diagnosed with MS every day. About 60% of adults newly diagnosed with MS are 20-49 years old. No wonder it is in the news.
For an excellent explanation of what MS is and how it is diagnosed, go to the Mayo Clinic’s page https://www.mayoclinic.org/diseases-conditions/multiple-sclerosis/ and listen to the video by Dr. B. Mark Keegan.
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 the myelin of the nerves. Myelin is like the insulation on a wire and the nerves are like the wire. Without adequate insulation, messages can be short-circuited, detoured, delayed, or interrupted, thus interfering with the brain’s ability to control muscles. The fundamental reason why this attack occurs is not known but it is clear that there is an association with a virus called Epstein-Barr. In many other autoimmune conditions, in which the body attacks itself, an infection is a trigger. Other triggers can be exposures to an external agent, such as a food. When the immune system reacts to the trigger it also reacts inadvertently to some part of the body that has a similar structure at the molecular level. Often these reactions seem to be unique to the person affected. This complexity is probably the main reason that MS is tricky to diagnose, treat, and cure.
Women are more likely to be affected by the Epstein-Barr virus, which is often found in their cells to be snugged up against the inactive X chromosomes. In women, one of the X chromosomes is rendered largely inactive. This is a balancing of the chromosomes so that men, who are XY, and women who are XX, are alike in the number of functional X’s. But why this virus is associated with the inactive X is a mystery. One of this year’s research grants, to Dr. Marc Horwitz at UBC, is targeted to this puzzle.
This may be 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. The rate on the Orkney Islands, (where all Heddles originated) is extremely high at 0.4%. As a large proportion of the Canadian population’s ancestors (72%) came from Scotland, England, Ireland, and Scandinavia, this could account for a higher rate of MS. It is not just being northerly that matters, however, as the Inuit and Sami, native to the north, do not have high rates, according to the Multiple Sclerosis Trust in the UK.
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 the treatments is activity, and it is quite effective.
The Multiple Sclerosis Society of Canada has an outstanding website (https://mssociety.ca/) with a great many pointers to sources of information and help for those affected and their care givers, including social, legal, and support matters. It reports that it is now, along with its affiliated MS Scientific Research Foundation, the single largest funder of MS research in Canada. It funds a variety of projects as shown by this diagram taken from its website. If you are interested in funding research, which is only a fraction of all of the expenditures of any such society, specify this with your donation.