A 30-year study of outcomes in multiple sclerosis (MS) patients reports that radiological findings in the first year of disease onset, and the amount of disability evident at five years, helps to predict both the likelihood of a person advancing to secondary progressive MS (SPMS) and long-term survival.
The study, “A thirty year clinical and MRI observational study of multiple sclerosis and clinically isolated syndromes,” was published in the journal Annals of Neurology.
MS is a highly variable disease, with neurological disability in some people remaining relatively minor for years while in others it’s quickly significant.
Many studies have shown that MS-related factors evident early in the disease course can predict later outcomes.
Researchers in the U.K. and colleagues conducted a 30-year longitudinal study to find potential early markers that could be used to predict which patients go on to develop progressive MS or have their life shortened by the disease.
Between 1984–87, a multi-national group of scientists recruited 132 people with clinically isolated syndrome (CIS), an episode of neurological symptoms that lasts at least 24 hours and could indicate a first course in MS disease.
These people were followed over time, clinically and radiologically (using imaging to detect abnormalities), and assessed at various time points: 1, 5, 10, 14, 20 and 30 years.
Data on their clinical outcomes were obtained from 120 of these patients at the 30-year mark. Of these, 80 people developed MS, and 16 (20%) died due to the disease.
Expanded disability status scale (EDSS), a method of quantifying disability in MS with higher EDSS scores indicating greater disability, were available from 107 participants, including 77 later diagnosed with MS.
EDSS scores indicated that 32 (42%) of these patients, all with relapsing-remitting MS (RRMS), remained fully ambulatory (EDSS equal or lower than 3.5) at 30 years. Greater disability (EDSS higher than 3.5) was evident in three (4%) RRMS patients, and 26 (34%) with SPMS.
The strongest early predictors of progression to SPMS (from RRMS) at 30 years were the presence at one year of baseline damage to the brain’s infratentorial region (which coordinates voluntary movements such as posture, balance, coordination, and speech), and in deep white matter (brain tissue that helps to quickly send and receive messages).
Thirty-year outcomes could also, in part, be predicted by early EDSS scores. A five-year EDSS score of 2.5 or higher was a significant predictor of SPMS development, as well as of death due to complications related to severe MS (an EDSS of 10).
Patients with a five-year EDSS of 2.5 or higher were at a 23.6-times higher risk of death over 30 years, compared to those with EDSS scores lower than 2.5.
Results of this three decade analysis of CIS patients showed three distinct MS outcomes over time: RRMS with little accrued disability (EDSS of 3.5 or lower), SPMS with impaired mobility (EDSS of 4.0 or higher), and those whose lives were shortened by MS (all of whom had SPMS).
“Thirty years after onset, in a largely untreated cohort, there was a divergence of MS outcomes; some people accrued substantial disability early on, while others ran a more favourable long-term course,” the researchers wrote.
“These outcomes could, in part, be predicted by radiological findings from within a year of first presentation,” they added.