[P01.138] Long Term Evolution of “Benign” Multiple Sclerosis Patients in the London Ontario Database Antonio Scalfari, Anneke Neuhaus, Martin Daumer, Paolo Muraro, George Ebers.
OBJECTIVE: Using conversion to secondary progressive (SP) multiple sclerosis (MS) as cutoff event for selecting patients with benign course, we tested which baseline features affects the probability of becoming "no longer benign" in the long term.
BACKGROUND: Clinical severity of MS is extremely variable. Patients with not more than moderate disability within 10-15 years from onset are regarded as "benign" however, lack of consensus exists.
DESIGN/METHODS: Among patients in the London Ontario database with benign course who had not experienced SP at 10 years from onset, binary logistic regression analysis assessed factors affecting the probability of remaining "benign" after 20 years.
RESULTS: Outcome at 20 years was known for 75% (n = 339/445) of those patients benign at 10 years from onset. Females predominated (71 %), mean age at onset was 26.8 years (S.D. 7.9) and most of patients had mono-symptomatic onset (71%) characterized by sensory disturbances (52.2%). Nearly half (166/339) had entered SP and were "no longer benign". Eventually, among this subgroup 91.5% (152/166) reached DSS 6, 60.8% (101/166) DSS 8 and 16.8% (28/166) DSS 10 in 19.9, 31.2 and 49.7 mean years respectively. Female sex (OR = 1.68; p = 0.032) and younger age at disease onset (age 21-30 Vs > 30: OR = 1.77, p = 0.02; age ≤ 20 Vs > 30: OR = 3.36, p < 0.001) associated with a higher probability of remaining benign at 20 years. Type and number of neurological systems at onset and early (year 1 + year 2) relapse frequency did not exert any predictive effect.
CONCLUSIONS: The onset of the SP phase is the watershed event differentiating benign cases. Lack of progression at 10 years from onset associated with about 50% probability of remaining benign 10 years later. Males and those older at disease onset had higher risk to become "no longer benign".
Warning this presentation has not been properly peer reviewed.
This study shows that so called benign MS is not inactive MS and that many years down the line progression may develop. This is further evidence that some sort of slow-burning disease process grumbles on in the absence of relapsing disease. Therefore it is clear that we will need agents to hinder this process straight from disease onset. This may well be (and probably is) totally independent of (auto)immunity, but we know that even in simple autoimmunity in animals that slow-burning neurodegenerative processes can be kicked off even after one attack, in others it takes a few attacks before it becomes more rapidly self-sustaining.