title: Deep brain stimulation improves orthostatic regulation of patients with Parkinson disease.
abstract: OBJECTIVE
  To evaluate whether subthalamic nucleus (STN) stimulation has an effect on the orthostatic regulation of patients with Parkinson disease (PD), we studied cardiovascular regulation during on and off phases of STN stimulation.
  
  
  METHODS
  We examined 14 patients with PD (mean age 58.1 +/- 5.8 years, 4 women, 10 men) with bilateral STN stimulators. Patients underwent 3 minutes of head-up tilt (HUT) testing during STN stimulation and after 90 minutes interruption of stimulation. We monitored arterial blood pressure (BP), RR intervals (RRI), respiration, and skin blood flow (SBF). Baroreflex sensitivity (BRS) was assessed as the square root of the ratio of low-frequency power of RRI to the low-frequency power of systolic BP for coherences above 0.5.
  
  
  RESULTS
  During the on phase of the STN stimulation, HUT induced no BP decrease, a significant tachycardia, and a significant decrease of SBF. During the off phase of stimulation, HUT resulted in significant decreases in BPsys and RRI and only a slight SBF decrease. HUT induced no change of BRS during stimulation, but lowered BRS when the stimulator was off (p < 0.05).
  
  
  CONCLUSIONS
  STN stimulation of patients with PD increases peripheral vasoconstriction and BRS and stabilizes BP, thereby improving postural hypotension in patients with PD. The results indicate that STN stimulation not only alleviates motor deficits but also influences autonomic regulation in patients with PD.
authors.affiliation: Department of Neurology, University of Erlangen-Nuernberg, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Stemper
authors.forename: A
authors.initials: A
authors.lastname: Beric
authors.forename: G
authors.initials: G
authors.lastname: Welsch
authors.forename: T
authors.initials: T
authors.lastname: Haendl
authors.forename: D
authors.initials: D
authors.lastname: Sterio
authors.forename: M J
authors.initials: MJ
authors.lastname: Hilz
mesh_terms: D017776:Autonomic Pathways / Q000503:physiopathology; D001794:Blood Pressure / Q000502:physiology; D001921:Brain / Q000503:physiopathology; D046690:Deep Brain Stimulation / Q000379:methods* / Q000592:standards / Q000639:trends; D005260:Female; D005712:Galvanic Skin Response / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications* / Q000503:physiopathology; D012039:Regional Blood Flow / Q000502:physiology; D012143:Respiratory Physiological Phenomena; D012791:Shy-Drager Syndrome / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy*; D020531:Subthalamic Nucleus / Q000502:physiology*; D016896:Treatment Outcome; D014661:Vasoconstriction / Q000502:physiology