Why do some people have a mild course of MS?
MRI experts weigh factors that may help determine when MS is “Benign”
“MS is notoriously unpredictable in its course,” commented John R. Richert, MD, a neurologist and head of the Society’s research and clinical programs, “and there’s no way to reliably predict over the long run whether a person will experience a mild or severe course.” Finding a way to predict who will have a mild course of MS would allow doctors to give better advice, and possibly spare some individuals from the expense and inconvenience of taking an MS therapy.
“Right now, the best advice we can give is to get on an MS therapy as soon as possible following a definite diagnosis of MS with active disease, and for many even after experiencing a first attack that puts them at high risk for developing MS,” said Dr. Richert. That’s because at the time of diagnosis and for years thereafter, it is impossible to know if the disease will be benign or more active, and early treatment is the best defense we have for slowing this disease.
Beyond prognosis, studying benign MS also holds promise for people with all types of MS: If we knew what made some people experience a mild course, that knowledge might be translated into slowing down the disease in people who experience more active MS.
A collaborating group of imaging experts from Europe, called MAGNIMS, recently held a workshop to review major MRI (magnetic resonance imaging) studies that have been done in people who had a benign course of MS (mild MS over 15 or more years), in comparison to those with more typical courses. MRI offers a window to MS activity in the brain that often doesn’t show up as obvious symptoms. The workshop results were recently published in the journal Neurology.
The investigators were seeking flags that might distinguish people with mild MS from those with more disabling forms of the disease, and also clues to what factors make a person’s MS course mild. While there was no slam-dunk -- no clear-cut MRI findings that were consistently unique to people with a benign course – they uncovered some significant trends.
In general, compared to more active forms of MS, they found that people with a benign course had fewer areas of damage (lesions) and shrinkage (atrophy) in specific areas of the brain critical to movement and other important functions that contribute to disability. These factors, along with the ability of the brain to compensate for damage by moving functions to other regions of the brain (a phenomenon called brain plasticity), may account for the milder course in people with benign MS.
Further research is needed to understand benign MS and to find early predictors that would help doctors advise people in their care. “The group’s urging that neurologists take into account individuals’ cognitive functions, not just their physical functions, when labeling a person’s MS as benign is an important one, and should lead to a refined definition of benign disease,” commented Dr. Richert.
The National MS Society’s National Clinical Advisory Board recommends that treatment with an immune-modulating drug (such as FDA-approved interferons or glatiramer acetate) be considered as soon as possible following a definite diagnosis of MS with active disease, and may also be considered for patients with a first attack who are at high risk of developing MS (known as clinically isolated syndrome). Because at the time of diagnosis and for some years thereafter it is impossible to know if disease will be benign or more active, this recommendation holds for people who present with a mild disease course.