P287 Longitudinal study of cortical excitability in treated versus untreated patients with progressive multiple sclerosis. Issue 9 (September 2017)

• Record Type: Journal Article
• Authors: Ayache, Samar S.; Créange, Alain; Lefaucheur, Jean-Pascal; Chalah, Moussa A.
• Is Part Of: Clinical neurophysiology. Volume 128:Issue 9(2017:Sep.)
• Page Start: e270
• Publication Date: 2017-09
• Subjects: Progressive MS -- Cortical excitability -- TMS -- RMT -- Intracortical facilitation -- Short-interval intracortical inhibition; Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2017.07.295
• Languages: English
• ISSNs: 1388-2457

Abstract

Abstract : Objectives: Transcranial magnetic stimulation (TMS) paradigms could be of help to get information on cortical excitability. This would enable a better understanding of pathophysiological mechanisms of various diseases and testing therapeutic responses. The objective of this study was to evaluate the cortical excitability of treated and untreated patients with progressive multiple sclerosis (MS). Methods: 34 patients were initially included and separated in two groups based on whether they are receiving or not disease-modifying therapies. Evaluation took place at baseline, 6 months and 12 months. Clinical evaluation included the expanded disability status scale (EDSS). Cortical excitability was assessed by TMS via various measures. Results: 25 patients completed the study. At baseline, treated patients had significantly higher motor evoked potentials (MEP) amplitude, and EDSS scores were inversely correlated with the resting MEP amplitude. At one year, contrarily to treated patients who did not experience any significant clinical or neurophysiological changes, untreated patients exhibited significant increase in resting motor threshold (rMT) and a reduction of short-interval intracortical inhibition (SICI). These changes were accompanied by an increase in EDSS score. Discussion: This pilot study illustrates the changes in cortical excitability parameters in untreated patients with progressive MS over a one-year follow-up. Conclusions: Disease modifying therapies might stabilize cortical excitability during the progressive phase of MS. Significance: Some cortical excitability measures may constitute biomarkers for monitoring the disease progression in MS.