title: Neurophysiological measurements of affected and unaffected motor cortex from a cross-sectional, multi-center individual stroke patient data analysis study.
abstract: OBJECTIVE
  Transcranial magnetic stimulation (TMS) has been used to measure cortical excitability as a functional measurement of corticomotor pathways. Given its potential application as an assessment tool in stroke, we aimed to analyze the correlation of TMS parameters with clinical features in stroke using data from 10 different centers.
  
  
  METHODS
  Data of 341 patients with a clinical diagnosis of stroke were collected from studies assessing cortical excitability using TMS. We used a multivariate regression model in which the baseline cortical excitability parameter "resting Motor Threshold (rMT)" was the main outcome and the demographic, anatomic and clinical characteristics were included as independent variables.
  
  
  RESULTS
  The variable "severity of motor deficit" consistently remained significant in predicting rMT in the affected hemisphere, with a positive β coefficient, in the multivariate models after sensitive analyses and adjusting for important confounders such as site center. Additionally, we found that the correlations between "age" or "time since stroke" and the rMT in the affected hemisphere were significant, as well as the interaction between "time since stroke" and "severity of motor deficit".
  
  
  CONCLUSIONS
  We have shown that severity of motor deficit is an important predictor for rMT in the affected hemisphere. Additionally, time since stroke seems to be an effect modifier for the correlation between motor deficit and rMT. In the unaffected motor cortex, these correlations were not significant. We discuss these findings in the context of stroke rehabilitation.
authors.affiliation: Harvard Medical School, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Laboratory of Neuromodulation, Boston, USA; Santa Casa Medical School, Division of Neurology, Sao Paulo, Brazil; University of Sao Paulo Medical School General Hospital, Physical and Rehabilitation Medicine Institute, Sao Paulo, Brazil.
authors.forename: Marcel
authors.initials: M
authors.lastname: Simis
authors.affiliation: Università Campus Biomedico, Institute of Neurology, Rome, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Di Lazzaro
authors.affiliation: University of Calgary, Alberta Children's Hospital Research Institute, Calgary Pediatric Stroke Program, Calgary, Alberta, Canada.
authors.forename: Adam
authors.initials: A
authors.lastname: Kirton
authors.affiliation: University of Catania, Section of Neurosciences, Department GF Ingrassia, Catania, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Pennisi
authors.affiliation: University of Catania, Section of Neurosciences, Department GF Ingrassia, Catania, Italy.
authors.forename: Rita
authors.initials: R
authors.lastname: Bella
authors.affiliation: Sungkyunkwan University, School of Medicine, Samsung Medical Center, Heart Vascular Stroke Institute, Department of Physical and Rehabilitation Medicine, Seoul, Republic of Korea.
authors.forename: Yun-Hee
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Tohoku University Graduates School of Medicine, Department of Physical Medicine and Rehabilitation, Sendai, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Takeuchi
authors.affiliation: Assiut University Hospital, Faculty of Medicine, Department of Neurology, Assiut, Egypt.
authors.forename: Eman M
authors.initials: EM
authors.lastname: Khedr
authors.affiliation: Rehabilitation Institute of Chicago, Sensory Motor Performance Program, Chicago, USA; Northwestern University Feinberg School of Medicine, Department of Physical Medicine and Rehabilitation, Chicago, USA.
authors.forename: Lynn M
authors.initials: LM
authors.lastname: Rogers
authors.affiliation: Rehabilitation Institute of Chicago, Sensory Motor Performance Program, Chicago, USA; Northwestern University Feinberg School of Medicine, Department of Physical Medicine and Rehabilitation, Chicago, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Harvey
authors.affiliation: Kyoto University Graduate School of Medicine, Human Brain Research Center, Kyoto, Japan.
authors.forename: Satoko
authors.initials: S
authors.lastname: Koganemaru
authors.affiliation: Bond University, School of Medicine, Robina, Australia.
authors.forename: Bulent
authors.initials: B
authors.lastname: Turman
authors.affiliation: Sifa University, Izmir, Turkey.
authors.forename: Sultan
authors.initials: S
authors.lastname: Tarlacı
authors.affiliation: Santa Casa Medical School, Division of Neurology, Sao Paulo, Brazil.
authors.forename: Rubens J
authors.initials: RJ
authors.lastname: Gagliardi
authors.affiliation: Harvard Medical School, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Laboratory of Neuromodulation, Boston, USA. Electronic address: Fregni.Felipe@mgh.harvard.edu.
authors.forename: Felipe
authors.initials: F
authors.lastname: Fregni
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D000071080:Cortical Excitability; D003430:Cross-Sectional Studies; D004568:Electrodiagnosis; D019054:Evoked Potentials, Motor; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000503:physiopathology*; D012044:Regression Analysis; D012720:Severity of Illness Index; D020521:Stroke / Q000175:diagnosis* / Q000503:physiopathology*; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult
keywords: Cerebrovascular disease; Cortical excitability; Excitabilité corticale; Maladie cérébrovasculaire; Stimulation magnétique transcrânienne; Transcranial magnetic stimulation