title: Long-term outcome of subthalamic nucleus DBS in Parkinson's disease: from the advanced phase towards the late stage of the disease?
abstract: BACKGROUND
  Deep Brain Stimulation of the Subthalamic Nucleus (STN-DBS) is an effective treatment for Parkinson's disease (PD), but only few studies investigated its long-term efficacy. Furthermore, little is known about the role of PD-subtype on STN-DBS long-term outcome.
  
  
  OBJECTIVE
  To report the results of a long-term follow-up (mean 11 years, range 10-13) on 26 patients bilaterally implanted in two centres.
  
  
  METHODS
  Patients were assessed preoperatively and 1, 5 and 11 years after the implant by the Unified Parkinson's Disease Rating Scale (UPDRS) and a battery of neuropsychological tests. Stimulation parameters, drugs dosages, non-motor symptoms and adverse events were also recorded.
  
  
  RESULTS
  At 11 years, stimulation significantly improved the motor symptoms by 35.8%, as compared to the preoperative off-state. Motor complications were well controlled, with a 84.6% improvement of dyskinesias and a 65.8% improvement of motor fluctuations. Despite this, the UPDRS-II-on score worsened by 88.5%, mainly for the worsening of poorly levodopa-responsive symptoms. More than 70% of the patients performed in the normal range in most of the neuropsychological tests, despite the development of dementia in 22.7%. Age at disease onset, axial subscore in off-condition and presence of REM behaviour disorder at baseline were found to be associated with a higher risk of developing disability over time.
  
  
  CONCLUSIONS
  Our study confirms the long-term safety and efficacy of STN-DBS in PD. Nevertheless, the functionality of patients worsens over time, mainly for the onset and progression of levodopa-resistant and non-motor symptoms. The role of PD-subtype seems to be relevant in the long-term outcome.
authors: University of Torino, 'Rita Levi Montalcini' Department of Neuroscience, Via Cherasco, 15, 10126 Torino, Italy.
authors: M G
authors: MG
authors: Rizzone
authors: University "Cattolica del Sacro Cuore", Department of Neurology, 00168 Roma, Italy.
authors: A
authors: A
authors: Fasano
authors: University "Cattolica del Sacro Cuore", Department of Neurology, 00168 Roma, Italy.
authors: A
authors: A
authors: Daniele
authors: University of Torino, 'Rita Levi Montalcini' Department of Neuroscience, Via Cherasco, 15, 10126 Torino, Italy.
authors: M
authors: M
authors: Zibetti
authors: University of Torino, 'Rita Levi Montalcini' Department of Neuroscience, Via Cherasco, 15, 10126 Torino, Italy.
authors: A
authors: A
authors: Merola
authors: University of Torino, 'Rita Levi Montalcini' Department of Neuroscience, Via Cherasco, 15, 10126 Torino, Italy.
authors: L
authors: L
authors: Rizzi
authors: University "Cattolica del Sacro Cuore", Department of Neurology, 00168 Roma, Italy.
authors: C
authors: C
authors: Piano
authors: University "Cattolica del Sacro Cuore", Department of Neurology, 00168 Roma, Italy.
authors: C
authors: C
authors: Piccininni
authors: Fondazione IRCCS Istituto Neurologico "Carlo Besta", 20133 Milano, Italy.
authors: L M
authors: LM
authors: Romito
authors: University of Torino, 'Rita Levi Montalcini' Department of Neuroscience, Via Cherasco, 15, 10126 Torino, Italy. Electronic address: leonardo.lopiano@unito.it.
authors: L
authors: L
authors: Lopiano
authors: University "Cattolica del Sacro Cuore", Department of Neurology, 00168 Roma, Italy; Fondazione IRCCS Istituto Neurologico "Carlo Besta", 20133 Milano, Italy.
authors: A
authors: A
authors: Albanese
mesh_terms: D000368:Aged; D046690:Deep Brain Stimulation / Q000379:methods*; D018450:Disease Progression; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology / Q000628:therapy*; D020531:Subthalamic Nucleus / Q000503:physiopathology*; D013995:Time
keywords: Deep brain stimulation; Parkinson's disease; Subthalamic nucleus