title: Exploring risk factors for stuttering development in Parkinson disease after deep brain stimulation.
abstract: Stuttering is a speech disorder with disruption of verbal fluency, occasionally present in Parkinson's disease (PD). PD co-incident stuttering may either worsen or improve after Deep Brain Stimulation (DBS).
  
  
  
  Sixteen out of 453 PD patients (3.5%) exhibited stuttering after DBS (PD-S) and were compared with a group of patients without stuttering (PD-NS) using non-parametric statistics.
  
  
  
  After DBS, stuttering worsened in 3 out of 4 patients with co-incidental stuttering. Most PD-S underwent subthalamic (STN) DBS, but 4 were implanted in the globus pallidus (GPi). Nine out of 16 PD-S (56.3%) reported a positive familial history for stuttering compared to none of the PD-NS. PD-S were mainly male (81.3%) with slight worse motor features compared to PD-NS.
  
  
  
  Herein, we describe a group of PD patients developing stuttering after DBS and report the presence of a positive familial history for stuttering as the most relevant risk factor, suggesting a possible underlying genetic cause. The fact that stuttering occurred after either STN or GPi DBS is an argument against the impact of medication reduction on stuttering.
authors.affiliation: Centre for Neurodegenerative Diseases (CEMAND), Department of Medicine and Surgery, Neuroscience Section, University of Salerno, Salerno, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Picillo
authors.affiliation: Movement Disorders Unit, Department of Neurology, Hospital Occidente de Kennedy, Universidad la Sabana, Bogota, Colombia.
authors.forename: Gustavo B
authors.initials: GB
authors.lastname: Vincos
authors.affiliation: Division of Neurosurgery, Department of Surgery, Krembil Neuroscience Centre, Toronto Western Hospital, University of Toronto, Canada.
authors.forename: Francesco
authors.initials: F
authors.lastname: Sammartino
authors.affiliation: Division of Neurosurgery, Department of Surgery, Krembil Neuroscience Centre, Toronto Western Hospital, University of Toronto, Canada; Krembil Research Institute, Toronto, Ontario, Canada.
authors.forename: Andres M
authors.initials: AM
authors.lastname: Lozano
authors.affiliation: Krembil Research Institute, Toronto, Ontario, Canada; Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital and Division of Neurology, University of Toronto, Toronto, Ontario, Canada; Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital and Division of Neurology, University of Toronto, Toronto, Ontario, Canada. Electronic address: alfonso.fasano@gmail.com.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Fasano
mesh_terms: D000368:Aged; D046690:Deep Brain Stimulation / Q000009:adverse effects* / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000628:therapy*; D012307:Risk Factors; D018709:Statistics, Nonparametric; D013342:Stuttering / Q000453:epidemiology / Q000209:etiology*
keywords: Deep brain stimulation; Parkinson disease; Speech; Stuttering; Surgery