Benign multiple sclerosis is a misleading and controversial term. Some neurologists do not recognize this as a form of MS at all. (Many people who meet the criteria for having benign MS will tell you that it certainly feels anything but benign.) Some believe that if people make it to 10 years without significant disability, they will not really progress to needing assistance to walk and may be able to stop treatment. Many others simply disagree with the classification and do not make treatment decisions based on a “benign” designation.
I sat in on one session at the 2015 meeting of the European Committee for Research and Treatment in Multiple Sclerosis, entitled “Long term course of apparently benign multiple sclerosis,” to see if the research was starting to clear the air.
The goal of this study was to compare disability progression in people who started out with benign MS to those who had more disability at 10 years after diagnosis. They looked at the Lyon (France) MS database and found 2641 people who qualified. At 10 years after diagnosis, 72% of the people could be classified as having benign MS. In this study, “benign MS” was defined as: “an irreversible Expanded Disability Status Scale (EDSS) score of 3.0 or lower at least 10 years after diagnosis.” According to the EDSS, a score of 3.0 means that there is “moderate disability in one functional system, or mild disability in three or four functional systems, but the person is fully ambulatory.”
A hallmark of progression to disability is an EDSS score of 6.0, which means that the person requires “intermittent or unilateral constant assistance (cane, crutch or brace) to walk 100 meters with or without resting.”
When the researchers looked at how people were doing 20 years after their diagnosis, about 60% of the people with non-benign MS progressed to an EDSS of 6.0, while only about 18% of the people with benign MS progressed to the same level.
Interested to see what other research showed, I looked at two other studies. In one study, entitled “Is it possible to predict benign multiple sclerosis?” researchers tried different criteria for “benign MS” to see if they could figure out the best predictors of who would not reach 6.0 on the EDSS. When they looked at an EDSS of less than or equal to 1.0 at 10 years after onset, they found that only 19.4% progressed to 6.0 by 20 years (similar to the first study).
A Swedish study, entitled “Long-term follow-up of initially benign multiple sclerosis patients: results from the Swedish multiple sclerosis register,” found that 28% of people who had been defined as having benign MS converted to secondary progressive MS (SPMS) at an average age of 66.5 years. 39% of people with non-benign MS converted to SPMS at 55.3 years old. Interestingly, people with benign MS reached an EDSS score of 6.0 at the average age of 79.3 years. People with non-benign MS had an EDSS score of 6.0 at 57.8 years.
Bottom Line: So, where does this leave us? Well, I went into this research hoping for some clear answers on what the designation of “benign” or “non-benign” MS really means for people living with the disease. What I came away thinking is that it is not really a useful designation.
Most importantly, I remain convinced that no treatment decisions should be made on a random label of “benign” or “non-benign” based on an EDSS score at 10 years following diagnosis. As is evident, some people accumulate more disability quicker than others, regardless of where they start out. Trying to play a statistics game with an extremely variable disease like MS may not be terribly helpful. However, continuing to do everything we can to live our lives to the fullest seems like a strategy we can all benefit from, regardless of any label that might include the word benign.