Here's a good paper listing research that links stress/trauma to MS...
I know Lars has had his head bonked as a rodeo rider. My Jeff's whacked his head repeatedly thruout his life since he has no peripheral vision, and walks into stuff (metal light poles, street signs, door jams, other people) with regularity. My pet name for him is Harry Headwound (SNL, anyone?)
Like JL says, everyone has a different recipe. My take on it is that the cerebral endothelium is weakened by a unique combo for each MS patient...whether it includes vaccines, toxins, stress, head trauma, viruses, lack of vit. D....each of these items is linked to endothelial disfunction and a change in nitric oxide. Correcting these issues with antioxidants, proteolytic enzymes, good nutrition, exercise, and stress reduction can return nitric oxide balance, help the BBB heal, and maybe keep MS in remission.