Abstract

There are few long-term clinical and magnetic resonance imaging (MRI) data on patients treated with interferon-beta (IFN-beta) for relapsing-remitting multiple sclerosis (RRMS). The aim of this study was to provide clinical and MRI data on 68 patients with RRMS treated over a 6-year period and to investigate whether a baseline MRI predicts their long-term clinical and MRI outcome. Six MRI scans were performed monthly before treatment and a further 13 scans were performed during treatment with IFN-beta, the last of which 6 years after commencement of treatment. The relapse rate, disability as measured by the Expanded Disability Status Scale (EDSS), and MRI parameters, including Gd-enhancing lesion load (Gd-LL), T2 hyperintense lesion load (T2-LL) T1 hypointense lesion load (T1-LL) and supratentorial brain volume (SBV) were measured throughout the study. The mean annual relapse rate over the 6 years was 0.52 (SD 0.67), which is significantly lower (68.6%) than the mean annual relapse rate of 1.6 observed during the 2-year period before the commencement of treatment (P