title: A Pilot Study Assessing the Effects of Pallidal Deep Brain Stimulation on Sleep Quality and Polysomnography in Parkinson's Patients.
abstract: OBJECTIVE
  Deep Brain Stimulation (DBS) is an established adjunctive surgical intervention to treat poorly controlled motor symptoms in Parkinson's disease (PD). Both surgical targets (the subthalamic nucleus and globus pallidus) have proven equally efficacious in treating motor symptoms but unique differences may exist in effects on nonmotor symptoms. Sleep dysfunction, a common disabling symptom in PD, has only been examined directly in the subthalamic target, demonstrating some beneficial changes in sleep quality. We aimed to explore sleep changes after pallidal stimulation; hypothesizing similar benefits would be seen.
  
  
  METHODS
  We performed a prospective nonblinded clinical trial evaluating sleep in five PD patients already slated for pallidal DBS pre and six months postimplantation using validated sleep surveys and polysomnograms (PSGs). Surveys included the Epworth sleepiness scale, PD sleep scale, Insomnia severity index (ISI), and RLS severity scale.
  
  
  RESULTS
  Most patients had notable improvements in sleep quality as measured by PSG metrics such as sleep efficiency and latency to sleep but they did not reach statistical significance. Most surveys reflected an improvement as well with the ISI scale showing the most promising trend post pallidal DBS (14.4 ± 7.02 vs. 9.0 ± 2.55; p = 0.07).
  
  
  CONCLUSIONS
  In this small pilot trial, pallidal DBS failed to demonstrate statistically significant improvements in sleep metrics postimplantation but did reveal improving trends in several PSG measures including sleep efficiency and latency to sleep onset as well as sleep survey scores. A larger, blinded clinical trial is needed to more definitively determine whether pallidal DBS may benefit sleep.
authors.affiliation: Department of Neurology, Movement Disorders Division, Vanderbilt University, Nashville, TN, USA. christopher.tolleson@vanderbilt.edu.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Tolleson
authors.affiliation: Department of Neurology, Sleep Division, Vanderbilt University, Nashville, TN, USA.
authors.forename: Kanika
authors.initials: K
authors.lastname: Bagai
authors.affiliation: Department of Neurology, Sleep Division, Vanderbilt University, Nashville, TN, USA.
authors.forename: Arthur S
authors.initials: AS
authors.lastname: Walters
authors.affiliation: Department of Neurology, Movement Disorders Division, Vanderbilt University, Nashville, TN, USA.
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Davis
mesh_terms: D000368:Aged; D046690:Deep Brain Stimulation / Q000379:methods*; D005260:Female; D005917:Globus Pallidus / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications* / Q000628:therapy; D010865:Pilot Projects; D017286:Polysomnography; D012893:Sleep Wake Disorders / Q000209:etiology* / Q000628:therapy*; D016896:Treatment Outcome
keywords: Parkinson's disease; deep brain stimulation; globus pallidus; sleep