title: The EP-score to assess treatment efficacy in RRMS patients: a preliminary study.
abstract: OBJECTIVE
  The aim of this retrospective study was to preliminarily assess whether the EP-score, a summary score derived from multimodal evoked potentials tests, might be used as a measure of treatment efficacy in multiple sclerosis (MS).
  
  
  METHODS
  A sample of 56 relapsing remitting MS (RRMS) patients who at diagnosis started treatment with interferon β (INFβ, n = 19), glatiramer acetate (GA, n = 15) or refused any chronic treatment were assessed at baseline (before treatment) and at a median of 1.7 and 3.6 years thereafter. Outcome variables were Expanded Disability Status Scale (EDSS), EP-Score, visual evoked potentials (VEP) and somatosensory evoked potentials (SEP) scores measured as differences between baseline and follow-ups. Statistical differences between groups and follow-ups were assessed using non-parametric analyses.
  
  
  RESULTS
  Treatment effects were not significant for EDSS both at the first and at the second follow-up, while a trend toward significance was observed in the EP-score only in the first follow-up (p = 0.07). Post-hoc analysis showed a greater decrease in median VEP-score for the IFNβ group compared to the GA and DF groups at both the first and second follow-ups.
  
  
  CONCLUSIONS
  We found no evidence that either INFβ or GA significantly improved disability in RRMS patients. Using the EP-score as an outcome measure, we found that it was improved at both follow-ups in the INFβ group mainly due to a decrease in the VEP-score. This finding supports the proposal to include the EP-score as an additional outcome variable in future studies of treatment efficacy in MS.
authors.affiliation: 1Laboratory of Clinical Neurophysiology.
authors.forename: Nicolò
authors.initials: N
authors.lastname: Margaritella
authors.forename: Laura
authors.initials: L
authors.lastname: Mendozzi
authors.forename: Massimo
authors.initials: M
authors.lastname: Garegnani
authors.forename: Raffaello
authors.initials: R
authors.lastname: Nemni
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Gilardi
authors.forename: Luigi
authors.initials: L
authors.lastname: Pugnetti
mesh_terms: D000328:Adult; D004185:Disability Evaluation; D006233:Persons with Disabilities; D004569:Electroencephalography; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D000068717:Glatiramer Acetate; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use; D016899:Interferon-beta / Q000627:therapeutic use; D008297:Male; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000175:diagnosis* / Q000188:drug therapy; D017063:Outcome Assessment, Health Care; D010455:Peptides / Q000627:therapeutic use; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D007155:Immunologic Factors; D010455:Peptides; D000068717:Glatiramer Acetate; D016899:Interferon-beta
keywords: EP-score; glatiramer acetate; interferon; multiple sclerosis; treatment response