open access
Corticomotor excitability in drug-naive patients with Parkinson disease
- Department of Clinical Neurophysiology, Institute of Psychiatry and Neurology, Warsaw, Poland
open access
Abstract
This study aimed to assess the indices of corticomotor excitability (CE) in drug-naive Parkinson disease (PD) patients and to investigate its relationship with asymmetry and severity of clinical symptoms.
Material and methodsEleven (4 men) drug-naive PD patients (mean age: 53.1 ± 9.8 years) and 13 (7 men) healthy controls (mean age: 51.7 ± 4.2 years) were included. All PD patients were rated on the motor section of the Unified Parkinson's Disease Rating Scale (UPDRS) with measurement of the side-specific score separately for arms and legs. Resting motor threshold (RMT), central silent period (CSP), amplitude of motor evoked potential (MEP) and central motor conduction time (CMCT) evoked by a single pulse of the transcranial magnetic stimulation were recorded in all subjects from the left and right abductor digiti minimi (ADM) and extensor digitorum brevis (EDB).
ResultsParkinson disease patients showed higher MEP (1.8 ± 0.9 vs. 1.1 ± 0.8 mV, p < 0.05) and shorter CMCT (6.1 ± 0.9 vs. 7.4 ± 1.0 ms, p < 0.05) recorded from the ADM on the more affected side. CSP recorded from the more affected ADM was under the normal range in five and from the less affected ADM in four PD patients. For CSP recorded from the EDB, respective values are four for the more affected side and three for the less affected side. The rigidity from the more affected arm and leg correlated negatively with the respective CSP recorded from the ADM (r = –0.74, p < 0.01) and EDB (r = –0.68, p < 0.04).
ConclusionsIn the early stage of untreated PD the CE parameters are altered only on the more affected side. The shortening of CSP reflects the severity of rigidity on the more affected side.
Abstract
This study aimed to assess the indices of corticomotor excitability (CE) in drug-naive Parkinson disease (PD) patients and to investigate its relationship with asymmetry and severity of clinical symptoms.
Material and methodsEleven (4 men) drug-naive PD patients (mean age: 53.1 ± 9.8 years) and 13 (7 men) healthy controls (mean age: 51.7 ± 4.2 years) were included. All PD patients were rated on the motor section of the Unified Parkinson's Disease Rating Scale (UPDRS) with measurement of the side-specific score separately for arms and legs. Resting motor threshold (RMT), central silent period (CSP), amplitude of motor evoked potential (MEP) and central motor conduction time (CMCT) evoked by a single pulse of the transcranial magnetic stimulation were recorded in all subjects from the left and right abductor digiti minimi (ADM) and extensor digitorum brevis (EDB).
ResultsParkinson disease patients showed higher MEP (1.8 ± 0.9 vs. 1.1 ± 0.8 mV, p < 0.05) and shorter CMCT (6.1 ± 0.9 vs. 7.4 ± 1.0 ms, p < 0.05) recorded from the ADM on the more affected side. CSP recorded from the more affected ADM was under the normal range in five and from the less affected ADM in four PD patients. For CSP recorded from the EDB, respective values are four for the more affected side and three for the less affected side. The rigidity from the more affected arm and leg correlated negatively with the respective CSP recorded from the ADM (r = –0.74, p < 0.01) and EDB (r = –0.68, p < 0.04).
ConclusionsIn the early stage of untreated PD the CE parameters are altered only on the more affected side. The shortening of CSP reflects the severity of rigidity on the more affected side.
Keywords
corticomotor excitability, transcranial magnetic stimulation, Parkinson disease
Title
Corticomotor excitability in drug-naive patients with Parkinson disease
Journal
Neurologia i Neurochirurgia Polska
Issue
Pages
109-115
Page views
370
Article views/downloads
494
DOI
10.5114/ninp.2013.34699
Bibliographic record
Neurol Neurochir Pol 2013;47(2):109-115.
Keywords
corticomotor excitability
transcranial magnetic stimulation
Parkinson disease
Authors
Mirosława Derejko
Maria Rakowicz
Jakub Antczak
Ewa Inglot
Maria Niewiadomska