A few years ago, on this forum or elsewhere, there was a presentation that MS may not all be auto-immune, but some kinds could be chemical. I have carried this one step further, to think that one form of chemically initiated MS could be from Porphyria, the second disease I was dx'd with. Porphyria could produce a chemical assault on the brain, but does not seem to make myelin scars in everyone; an "expert" estimated 17% of those with Porphyria have the white spots shown on MRI.

As for athersclerosis, I have been tested for this over the years. When young and having MS symptoms, very clear arteries--a doctor who did a test said "I wish I had your arteries, like a teenager's." Then later, in old age, I have slight athersclerotic narrowing, or whatever you call it as it has not been discussed at length with me, but it is slight. I was tested for this because of my third disease, Polycythemia Vera, which produces "thick blood." I have to thin my blood with phelbotomies and now p32 and aspirin, but I don't have significantly narrowed arteries. I do have pain in my microvessels in my feet if I let the blood particles get too many. Very bad pain there but nothing else of vascular pain.

It is fascinating to me that Dr. Swank, whom I saw 24 years ago, believed that we with MS have slow moving blood. Blood particles stick together more readily, and one can see this on a microscope. He showed me my blood particles sticking and moving slowly,
and confirmed my previous MS dx. For a while he was treating MS patients with transfusions from normal-blooded relatives. He insisted on relatives or very close friends to avoid contaminated blood. I was too sick at the time to go through the hoops to drive to Portland and have my husband go with me, and my husband was working at that time, and it would have been a hardship, so I never tried this. One also had to take Benadryl to avoid allergic response to even the relative's matched blood (Irv's and mine were a match) and I knew I would become ill from Benadryl. Later my becoming ill from Benadryl was explained, because people with Porphyria can't usually take it (I can take Zyrtec instead).
Dr. Swank said that some MS patients who had not been walking started to walk, even wearing "heels", after the transfusions, but they lasted only about five months. Not a cure.
Swank was such a wonderful researcher and got little support for doing it. He got more support in England and was doing research there, and my blood was sent there, among others, for his research. But I don't think he completed that. He died at about 97 a few years ago, a great man who was appreciated by patients but not enough by other doctors.