Multicentre assessment of motor and sensory evoked potentials in multiple sclerosis: reliability and implications for clinical trials

• Published in: Multiple sclerosis journal - experimental, translational and clinical Vol. 5; no. 2; p. 2055217319844796
• Main Authors: Hardmeier, Martin, Jacques, François, Albrecht, Philipp, Bousleiman, Habib, Schindler, Christian, Leocani, Letizia, Fuhr, Peter
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.04.2019; Sage Publications Ltd
• Subjects: Biomarkers; Clinical trials; Multiple sclerosis; Original Research Paper; progressive MS; response biomarker; sensory evoked potentials; Motor evoked potentials; test–retest reliability; biomarker; mean detectable change; remyelination
• ISSN: 2055-2173; 2055-2173
• DOI: 10.1177/2055217319844796

Background Motor and sensory evoked potentials (EP) are potential candidate biomarkers for clinical trials in multiple sclerosis. Objective To determine test -retest reliability of motor EP (MEP) and sensory EP (SEP) and associated EP-scores in patients with multiple sclerosis. Methods In three centres, 16 relapsing and five progressive multiple sclerosis patients had MEPs and SEPs 1–29 days apart. Five neurophysiologists independently marked latencies by central reading. By variance component analysis, we estimated the critical difference (absolute reliability) for cross-sectional group comparison, comparison of longitudinal group changes, within-subject minimal detectable change and defined within-subject improvement. Results Cortical SEP responses and cortico-muscular MEP latencies were more reliable than central conduction times. For comparison of 20 subjects per arm, cross-sectional group difference ranged from 0.7 to 3.9 ms and 1.1 to 1.7, group difference in longitudinal changes from 0.4 to 1.8 ms and 0.36 to 0.62, within-subject minimal detectable change from 1.2 to 5.8 ms and 1.2 to 2.0, within-subject improvement from 0.8 to 3.8ms and 0.8 to 1.3, for single EP modalities and EP scores, respectively. Conclusions Multicentre EP assessment with central EP reading is feasible and reliable. The critical difference is reasonably low to detect significant group changes and to define responders. The results support the concept of using EP and EP-scores as candidate response biomarkers for quantification of disease progression and for studying remyelination in multiple sclerosis.