Predictors of short-term disease activity following a first clinical demyelinating event: analysis of the CHAMPS placebo group

We evaluated 190 patients in the placebo group of the CHAMPS trial in order to assess factors associated with short-term dinical and brain magnetic resonance imaging (MRI) outcomes in patients with a first dinical demyelinating event involving the optic nerve, spinal cord, or brainstem/cerebellum, and subdinical demyelination on brain MRI. The two study outcomes were 1) development of clinically definite multiple sclerosis (CDMS) and 2) development of CDMS or two or more new or enlarging brain MRI T2 lesions. The presence of gadolinium (Gd)-enhancing lesions on the baseline scan was the only MRI characteristic associated with a higher risk of both the clinical and combined outcomes (p = 0.003 and < 0.001, respectively). The only demographic or clinical characteristic associated with an increased risk of these outcomes was younger age (p < 0.001 for both outcomes). The lowest risk subgroups we could define had a 30% risk of CDMS and a 65% risk of the combined clinical/MRI outcome. Our results indicate that all patients presenting with a first demyelinating event who also have brain MRI evidence of subclinical demyelination have at least a moderate risk of short-term disease activity. This finding provides support for initiating disease-modifying therapy at the time of the first demyelinating event in patients meetng the CHAMPS enrollment criteria.