Neuropsychological assessment, quantitative MRI and ApoE gene polymorphisms in a series of MS patients treated with IFN beta-1b

Few trials issued the effect of disease-modifying medications on cognitive functions in multiple sclerosis. We designed an open-label longitudinal study to evaluate, during 2 years, cognitive performance and its relationship with MRI data and ApoE polymorphism findings in a group of relapsing-remitting (RR) multiple sclerosis (MS) Interferon (IFN) beta-1b-treated patients (median age 30 years, median disease duration 3.4 years). Complete neuropsychological battery was grouped into attention, information learning/memory, language and visuo-spatial functions. Fifty-two patients (33 females) were enrolled in the study. Six patients (11.5%) dropped out, mainly due to side effects. At baseline neuropsychological evaluation, we found 54% normal, 42% mildly impaired and 4% moderately impaired patients. At 2 years follow-up, cognitive status was stable in 65%, improved in 33% and worsened in 2% of patients. No significant relations were found between global cognitive outcome vs. EDSS change, clinical disease activity, MRI data or ApoE gene polymorphisms over the 2 years follow-up. EDSS and MRI fractional volumes were found to correlate with the performance at single tests. Twenty-one patients (45.6%) showed active MRI scans throughout the study, without any worsening at the corresponding neuropsychological examination. This ongoing trial suggests a possible beneficial effect of IFN beta-1b treatment on cognitive functions in RRMS patients. Extension of follow-up and further data analyses are needed to confirm and clarify these findings.