title: Outcome Prediction of Consciousness Disorders in the Acute Stage Based on a Complementary Motor Behavioural Tool.
abstract: BACKGROUND
  Attaining an accurate diagnosis in the acute phase for severely brain-damaged patients presenting Disorders of Consciousness (DOC) is crucial for prognostic validity; such a diagnosis determines further medical management, in terms of therapeutic choices and end-of-life decisions. However, DOC evaluation based on validated scales, such as the Revised Coma Recovery Scale (CRS-R), can lead to an underestimation of consciousness and to frequent misdiagnoses particularly in cases of cognitive motor dissociation due to other aetiologies. The purpose of this study is to determine the clinical signs that lead to a more accurate consciousness assessment allowing more reliable outcome prediction.
  
  
  METHODS
  From the Unit of Acute Neurorehabilitation (University Hospital, Lausanne, Switzerland) between 2011 and 2014, we enrolled 33 DOC patients with a DOC diagnosis according to the CRS-R that had been established within 28 days of brain damage. The first CRS-R assessment established the initial diagnosis of Unresponsive Wakefulness Syndrome (UWS) in 20 patients and a Minimally Consciousness State (MCS) in the remaining13 patients. We clinically evaluated the patients over time using the CRS-R scale and concurrently from the beginning with complementary clinical items of a new observational Motor Behaviour Tool (MBT). Primary endpoint was outcome at unit discharge distinguishing two main classes of patients (DOC patients having emerged from DOC and those remaining in DOC) and 6 subclasses detailing the outcome of UWS and MCS patients, respectively. Based on CRS-R and MBT scores assessed separately and jointly, statistical testing was performed in the acute phase using a non-parametric Mann-Whitney U test; longitudinal CRS-R data were modelled with a Generalized Linear Model.
  
  
  RESULTS
  Fifty-five per cent of the UWS patients and 77% of the MCS patients had emerged from DOC. First, statistical prediction of the first CRS-R scores did not permit outcome differentiation between classes; longitudinal regression modelling of the CRS-R data identified distinct outcome evolution, but not earlier than 19 days. Second, the MBT yielded a significant outcome predictability in the acute phase (p<0.02, sensitivity>0.81). Third, a statistical comparison of the CRS-R subscales weighted by MBT became significantly predictive for DOC outcome (p<0.02).
  
  
  CONCLUSIONS
  The association of MBT and CRS-R scoring improves significantly the evaluation of consciousness and the predictability of outcome in the acute phase. Subtle motor behaviour assessment provides accurate insight into the amount and the content of consciousness even in the case of cognitive motor dissociation.
authors.affiliation: Acute Neurorehabilitation Unit, Department of Clinical Neurosciences, University Hospital of Lausanne, Lausanne, Switzerland.|Department of Clinical Neurosciences, University Hospital of Lausanne, Lausanne, Switzerland.
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Pignat
authors.affiliation: Faculty of Medicine, Lausanne University, Lausanne, Switzerland.
authors.forename: Etienne
authors.initials: E
authors.lastname: Mauron
authors.affiliation: Acute Neurorehabilitation Unit, Department of Clinical Neurosciences, University Hospital of Lausanne, Lausanne, Switzerland.
authors.forename: Jane
authors.initials: J
authors.lastname: Jöhr
authors.affiliation: Acute Neurorehabilitation Unit, Department of Clinical Neurosciences, University Hospital of Lausanne, Lausanne, Switzerland.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Gilart de Keranflec'h
authors.affiliation: Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.|Faculty of Medicine, University of Geneva, Geneva, Switzerland.
authors.forename: Dimitri
authors.initials: D
authors.lastname: Van De Ville
authors.affiliation: Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.|Faculty of Medicine, University of Geneva, Geneva, Switzerland.
authors.forename: Maria Giulia
authors.initials: MG
authors.lastname: Preti
authors.affiliation: Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.|Faculty of Medicine, University of Geneva, Geneva, Switzerland.
authors.forename: Djalel E
authors.initials: DE
authors.lastname: Meskaldji
authors.affiliation: Department of Neurology, SRH-Gesundheitszentrum, Bad Wimpfen, Germany.
authors.forename: Volker
authors.initials: V
authors.lastname: Hömberg
authors.affiliation: Coma Science Group, University of Liege, Liege, Belgium.
authors.forename: Steven
authors.initials: S
authors.lastname: Laureys
authors.affiliation: Department of Clinical Neurosciences, University Hospital of Lausanne, Lausanne, Switzerland.
authors.forename: Bogdan
authors.initials: B
authors.lastname: Draganski
authors.affiliation: Department of Clinical Neurosciences, University Hospital of Lausanne, Lausanne, Switzerland.
authors.forename: Richard
authors.initials: R
authors.lastname: Frackowiak
authors.affiliation: Acute Neurorehabilitation Unit, Department of Clinical Neurosciences, University Hospital of Lausanne, Lausanne, Switzerland.|Department of Clinical Neurosciences, University Hospital of Lausanne, Lausanne, Switzerland.
authors.forename: Karin
authors.initials: K
authors.lastname: Diserens
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003244:Consciousness Disorders / Q000175:diagnosis* / Q000503:physiopathology / Q000534:rehabilitation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010808:Physical Examination; D011379:Prognosis; D020127:Recovery of Function / Q000502:physiology*; D016896:Treatment Outcome; D055815:Young Adult