title: Combined visual and motor evoked potentials predict multiple sclerosis disability after 20 years.
abstract: BACKGROUND
  The development of predictors of multiple sclerosis (MS) disability is difficult due to the complex interplay of pathophysiological and adaptive processes.
  
  
  OBJECTIVE
  The purpose of this study was to investigate whether combined evoked potential (EP)-measures allow prediction of MS disability after 20 years.
  
  
  METHODS
  We examined 28 patients with clinically definite MS according to Poser's criteria with Expanded Disability Status Scale (EDSS) scores, combined visual and motor EPs at entry (T0), 6 (T1), 12 (T2) and 24 (T3) months, and a cranial magnetic resonance imaging (MRI) scan at T0 and T2. EDSS testing was repeated at year 14 (T4) and year 20 (T5). Spearman rank correlation was used. We performed a multivariable regression analysis to examine predictive relationships of the sum of z-transformed EP latencies (s-EPT0) and other baseline variables with EDSST5.
  
  
  RESULTS
  We found that s-EPT0 correlated with EDSST5 (rho=0.72, p<0.0001) and ΔEDSST5-T0 (rho=0.50, p=0.006). Backward selection resulted in the prediction model: E (EDSST5)=3.91-2.22×therapy+0.079×age+0.057×s-EPT0 (Model 1, R (2)=0.58) with therapy as binary variable (1=any disease-modifying therapy between T3 and T5, 0=no therapy). Neither EDSST0 nor T2-lesion or gadolinium (Gd)-enhancing lesion quantities at T0 improved prediction of EDSST5. The area under the receiver operating characteristic (ROC) curve was 0.89 for model 1.
  
  
  CONCLUSIONS
  These results further support a role for combined EP-measures as predictors of long-term disability in MS.
authors.affiliation: Department of Neurology, University Hospital Basel, Switzerland.
authors.forename: Regina
authors.initials: R
authors.lastname: Schlaeger
authors.affiliation: Swiss Tropical and Public Health Institute, Basel, Switzerland University of Basel, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Schindler
authors.affiliation: Swiss Tropical and Public Health Institute, Basel, Switzerland University of Basel, Switzerland.
authors.forename: Leticia
authors.initials: L
authors.lastname: Grize
authors.affiliation: Department of Radiology, University Hospital Basel, Switzerland.
authors.forename: Sophie
authors.initials: S
authors.lastname: Dellas
authors.affiliation: Department of Radiology, University Hospital Basel, Switzerland Medical Image Analysis Centre, University Hospital Basel, Switzerland.
authors.forename: Ernst W
authors.initials: EW
authors.lastname: Radue
authors.affiliation: Department of Neurology, University Hospital Basel, Switzerland University of Basel, Switzerland.
authors.forename: Ludwig
authors.initials: L
authors.lastname: Kappos
authors.affiliation: Department of Neurology, University Hospital Basel, Switzerland University of Basel, Switzerland Peter.Fuhr@usb.ch.
authors.forename: Peter
authors.initials: P
authors.lastname: Fuhr
mesh_terms: D000328:Adult; D019540:Area Under Curve; D003287:Contrast Media; D004185:Disability Evaluation; D018450:Disease Progression; D004558:Electric Stimulation; D004569:Electroencephalography; D019054:Evoked Potentials, Motor; D005074:Evoked Potentials, Visual; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D015999:Multivariate Analysis; D010775:Photic Stimulation; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D011930:Reaction Time; D013997:Time Factors
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA
keywords: Evoked potentials; magnetic resonance imaging; multiple sclerosis; prognosis