title: Does early verbal fluency decline after STN implantation predict long-term cognitive outcome after STN-DBS in Parkinson's disease?
abstract: BACKGROUND
  An early and transient verbal fluency (VF) decline and impairment in frontal executive function, suggesting a cognitive microlesion effect may influence the cognitive repercussions related to subthalamic nucleus deep brain stimulation (STN-DBS).
  
  
  METHODS
  Neuropsychological tests including semantic and phonemic verbal fluency were administered both before surgery (baseline), the third day after surgery (T3), at six months (T180), and at an endpoint multiple years after surgery (Tyears).
  
  
  RESULTS
  Twenty-four patients (mean age, 63.5 ± 9.5 years; mean disease duration, 12 ± 5.8 years) were included. Both semantic and phonemic VF decreased significantly in the acute post-operative period (44.4 ± 28.2% and 34.3 ± 33.4%, respectively) and remained low at 6 months compared to pre-operative levels (decrease of 3.4 ± 47.8% and 10.8 ± 32.1%) (P < 0.05). Regression analysis showed phonemic VF to be an independent factor of decreased phonemic VF at six months. Age was the only independent predictive factor for incident Parkinson's disease dementia (PDD) (F (4,19)=3.4, P<0.03).
  
  
  CONCLUSIONS
  An acute post-operative decline in phonemic VF can be predictive of a long-term phonemic VF deficit. The severity of this cognitive lesion effect does not predict the development of dementia which appears to be disease-related.
authors.affiliation: Department of Neurology, Rouen University Hospital, University of Rouen, France.
authors.forename: Alaina
authors.initials: A
authors.lastname: Borden
authors.affiliation: Department of Neurology, Rouen University Hospital, University of Rouen, France; Department of Neurosurgery, Rouen University Hospital, University of Rouen, France.
authors.forename: David
authors.initials: D
authors.lastname: Wallon
authors.affiliation: Department of Neurology, Rouen University Hospital, University of Rouen, France.
authors.forename: Romain
authors.initials: R
authors.lastname: Lefaucheur
authors.affiliation: Department of Neurosurgery, Rouen University Hospital, University of Rouen, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Derrey
authors.affiliation: Department of Neurology, Rouen University Hospital, University of Rouen, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Fetter
authors.affiliation: Department of Neurology, University Hospital of Rennes, France; EA 4712 "Behavior and Basal Ganglia", Rennes 1 University, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Verin
authors.affiliation: Department of Neurology, Rouen University Hospital, University of Rouen, France; INSERM U1079, Rouen Faculty of Medicine, France. Electronic address: david.maltete@chu-rouen.fr.
authors.forename: David
authors.initials: D
authors.lastname: Maltête
mesh_terms: D000328:Adult; D000368:Aged; D003071:Cognition / Q000502:physiology*; D046690:Deep Brain Stimulation; D056344:Executive Function / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000503:physiopathology* / Q000628:therapy; D013060:Speech / Q000502:physiology*; D020531:Subthalamic Nucleus / Q000503:physiopathology* / Q000601:surgery; D016896:Treatment Outcome
keywords: Deep brain stimulation; Dementia; Microlesion; Parkinson's disease; Subthalamic nucleus; Verbal fluency