Brain volume loss and physical and cognitive impairment in naïve multiple sclerosis patients treated with fingolimod: prospective cohort study in Buenos Aires, Argentina

BACKGROUND: The percentage of brain volume loss (PBVL) has been classically considered as a biomarker in multiple sclerosis (MS). OBJECTIVE: The objective of the present study was to analyze if the PBVL during the 1(st) year after the onset of the disease predicts physical and cognitive impairment (CI). METHODS: Prospective study that included naïve patients without cognitive impairment who initiated MS treatment with fingolimod. Patients were followed for 3 years and relapses, expanded disability status scale (EDSS) progression (defined as worsening of 1 point on the EDSS), the annual PBVL (evaluated by structural image evaluation using normalization of atrophy [SIENA]), and the presence of CI were evaluated. Cognitive impairment was defined in patients who scored at least 2 standard deviations (SDs) below controls on at least 2 domains. The PBVL after 1 year of treatment with fingolimod was used as an independent variable, while CI and EDSS progression at the 3(rd) year of follow-up as dependent variables. RESULTS: A total of 71 patients were included, with a mean age of 35.4 ± 3 years old. At the 3(rd) year, 14% of the patients were classified as CI and 6.2% had EDSS progression. In the CI group, the PBVL during the 1(st) year was-0.52 (± 0.07) versus-0.42 (± 0.04) in the no CI group (p < 0.01; odds ratio [OR] = 2.24; 95% confidence interval [CI]: 1.72–2.44). In the group that showed EDSS progression, the PBVL during the 1(st) year was - 0.59 (± 0.05) versus - 0.42 (± 0.03) (p < 0.01; OR = 2.33; 95%CI: 1.60-2.55). CONCLUSIONS: A higher PBVL during the 1(st) year in naïve MS patients was independently associated with a significant risk of CI and EDSS progression.