Background and Objective: The objective of this study was to examine the effects of natalizumab on functional parameters assessed by evoked potentials (visual [VEP], somatosensory [SEP] and motor evoked potentials [MEP]) in a cohort study in relapsing–remitting multiple sclerosis patients.
Methods: EP data of 44 patients examined 12 months prior to natalizumab treatment, at the timepoint of treatment initiation and 1 year later were compared. Sum scores (VEP, MEP, SEP) were evaluated and correlated with the Expanded Disability Status Scale.
Results: Improvement of the VEP sum score was found in 33% of natalizumab-treated patients but only in 9% of the same patients prior to treatment (p = 0.041). A comparable situation was found for SEP (improvement: 32% versus 5%; worsening: 11% versus 37%; p = 0.027). For MEP no significant differences were seen (improvement: 10% versus 18%; worsening: 5% versus 29%; p = 0.60). EP recordings (VEP = SEP > MEP) have the capacity to demonstrate treatment effects of natalizumab on a functional level.
Conclusions: Natalizumab therapy increases the percentage of patients showing stable or even ameliorated electrophysiological parameters in the investigated functional systems.
PolmanCHO’ConnorPWHavrdovaEHutchinsonMKapposLMillerDH. A randomized, placebo-controlled trial of natalizumab for relapsing multiple sclerosis. N Engl J Med2006; 354: 899–910.
2.
RudickRAStuartWHCalabresiPAConfavreuxCGalettaSLRadueEW. Natalizumab plus interferon beta-1a for relapsing multiple sclerosis. N Engl J Med2006; 354: 911–923.
3.
HavrdovaEGalettaSHutchinsonMStefoskiDBatesDPolmanCH. Effect of natalizumab on clinical and radiological disease activity in multiple sclerosis: a retrospective analysis of the Natalizumab Safety and Efficacy in Relapsing-Remitting Multiple Sclerosis (AFFIRM) study. Lancet Neurol2009; 8: 254–260.
4.
BalcerLJBaierMLCohenJAKooijmansMFSandrockAWNano-SchiaviML. Contrast letter acuity as a visual component for the Multiple Sclerosis Functional Composite. Neurology2003; 61: 1367–1373.
5.
BalcerLJGalettaSLCalabresiPAConfavreuxCGiovannoniGHavrdovaE. Natalizumab reduces visual loss in patients with relapsing multiple sclerosis. Neurology2007; 68: 1299–1304.
6.
StoneLA. Getting the measure of multiple sclerosis. Lancet Neurol2009; 8: 221–222.
7.
RudickRAPolmanCHCohenJAWaltonMKMillerAEConfavreuxC. Assessing disability progression with the Multiple Sclerosis Functional Composite. Mult Scler2009; 15: 984–997.
PolmanCHReingoldSCEdanGFilippiMHartungHPKapposL. Diagnostic criteria for multiple sclerosis: 2005 revisions to the “McDonald Criteria”. Ann Neurol2005; 58: 840–846.
10.
KallmannBAFackelmannSToykaKVRieckmannPReinersK. Early abnormalities of evoked potentials and future disability in patients with multiple sclerosis. Mult Scler2006; 12: 58–65.
11.
MeyerBUBrittonTCBeneckeRBischoffCMachetanzJConradB. Motor responses evoked by magnetic brain stimulation in psychogenic limb weakness: diagnostic value and limitations. J Neurol1992; 239: 251–255.
12.
KurtzkeJF. Rating neurologic impairment in multiple sclerosis: an expanded disability status scale (EDSS). Neurology1983; 33: 1444–1452.
CliffordDBDe LucaASimpsonDMArendtGGiovannoniGNathA. Natalizumab-associated progressive multifocal leukoencephalopathy in patients with multiple sclerosis: lessons from 28 cases. Lancet Neurol2010; 9: 438–446.
15.
WhiteATPetajanJH. Physiological measures of therapeutic response to interferon beta-1a treatment in remitting-relapsing MS. Clin Neurophysiol2004; 115: 2364–2371.
16.
AnlarOKisliMTombulTOzbekH. Visual evoked potentials in multiple sclerosis before and after two years of interferon therapy. Int J Neurosci2003; 113: 483–489.
17.
LiscicRMBreceljJ. Visual evoked potentials in multiple sclerosis patients treated with interferon beta-1a. Croat Med J2004; 45: 323–327.
18.
FuhrPBorggrefe-ChappuisASchindlerCKapposL. Visual and motor evoked potentials in the course of multiple sclerosis. Brain2001; 124: 2162–2168.
19.
Weinstock-GuttmanBBaierMStocktonRWeinstockAJustingerTMunschauerF. Pattern reversal visual evoked potentials as a measure of visual pathway pathology in multiple sclerosis. Mult Scler2003; 9: 529–534.
20.
JungPBeyerleAZiemannU. Multimodal evoked potentials measure and predict disability progression in early relapsing-remitting multiple sclerosis. Mult Scler2008; 14: 553–556.
