BARCELONA—In the months following a first clinical event suggestive of multiple sclerosis (MS), MRI findings and Expanded Disability Status Scale (EDSS) score can help predict which patients will have sustained disability progression, according to the results of a longitudinal study presented at the 31st Congress of the European Committee for Treatment and Research in MS (ECTRIMS). The significance of these findings lies in the fact that MS is a heterogeneous disease with a broad spectrum of phenotypes, which makes it difficult to predict disease course, said Tomas Uher, MD, a neurologist at Charles University in Prague. Thus, early identification of patients with MS who are at the highest risk of disease progression may help guide therapeutic decision making.
Testing MRI and Clinical Indicators
The current investigation was a substudy of the Study of Early Interferon β1-a Treatment in High Risk Subjects after Clinically Isolated Syndrome (SET). The primary outcome was sustained disability progression, defined as a 1.0-point increase in the EDSS confirmed after 12 months or, if the EDSS score was 0 at baseline, an increase of 1.5 points.
A total of 210 patients who had had a first clinical event suggestive of MS within the previous four months were included in the analysis. Subjects had a baseline EDSS score of 3.5 or lower, at least two T2 lesions as seen on brain MRI, and at least two CSF-restricted oligoclonal bands. In addition to MRI assessment at baseline, six months, and 12 months, patients underwent clinical visits every three months and were followed for a minimum of four years, with an average follow-up duration of six years. Sixty-six percent of participants were women, and the population’s mean age was 29.
A total of 42 clinical and MRI predictors were analyzed, including the MS Functional Composite and gray matter and white matter volume change. Results were adjusted for age, sex, and disease duration.
Significantly Increased Risks
By study’s end, 61% of subjects had experienced a new relapse, and 20% had experienced sustained disability progression. Statistically significant factors shown to be the best predictors of disease progression were any new relapse, any change in EDSS score, and T1 lesion volume greater than 1.25 mL at six months or at 12 months; a decrease in corpus callosum volume greater than 0.5% and whole-brain volume change greater than 0.4% at six months; and corpus callosum change greater than 0.7% at 12 months.
“When we looked at individual predictors, we found that patients had a twofold to as much as a fivefold greater risk of disability progression, compared with patients who didn’t fulfill the criteria,” Dr. Uher noted. For example, the hazard ratio for sustained disease progression was 2.2 for new relapse at six months, 3.3 for corpus callosum volume decrease at six months, and 4.9 for EDSS change at 12 months.
Further studies are needed to confirm these results, as well as to determine which disease-modifying therapies would prevent disability progression in patients at highest risk. Additional studies also are needed to evaluate the feasibility of MRI volumetry in clinical practice, Dr. Uher concluded.
—Adriene Marshall