title: Cognitive and Psychiatric Effects of STN versus GPi Deep Brain Stimulation in Parkinson's Disease: A Meta-Analysis of Randomized Controlled Trials.
abstract: BACKGROUND
  Deep brain stimulation (DBS) of either the subthalamic nucleus (STN) or the globus pallidus interna (GPi) can reduce motor symptoms in patients with Parkinson's disease (PD) and improve their quality of life. However, the effects of STN DBS and GPi DBS on cognitive functions and their psychiatric effects remain controversial. The present meta-analysis was therefore performed to clarify these issues.
  
  
  METHODS
  We searched the PUBMED, EMBASE, and the Cochrane Central Register of Controlled Trials databases. Other sources, including internet-based clinical trial registries and grey literature sources, were also searched. After searching the literature, two investigators independently performed literature screens to assess the quality of the included trials and to extract the data. The outcomes included the effects of STN DBS and GPi DBS on multiple cognitive domains, depression, anxiety, and quality of life.
  
  
  RESULTS
  Seven articles related to four randomized controlled trials that included 521 participants were incorporated into the present meta-analysis. Compared with GPi DBS, STN DBS was associated with declines in selected cognitive domains after surgery, including attention, working memory and processing speed, phonemic fluency, learning and memory, and global cognition. However, there were no significant differences in terms of quality of life or psychiatric effects, such as depression and anxiety, between the two groups.
  
  
  CONCLUSIONS
  A selective decline in frontal-subcortical cognitive functions is observed after STN DBS in comparison with GPi DBS, which should not be ignored in the target selection for DBS treatment in PD patients. In addition, compared to GPi DBS, STN DBS does not affect depression, anxiety, and quality of life.
authors.affiliation: Beijing Institute of Functional Neurosurgery, Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, P.R. China.
authors.forename: Jia-Wei
authors.initials: JW
authors.lastname: Wang
authors.affiliation: Beijing Institute of Functional Neurosurgery, Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, P.R. China.
authors.forename: Yu-Qing
authors.initials: YQ
authors.lastname: Zhang
authors.affiliation: Beijing Institute of Functional Neurosurgery, Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, P.R. China.
authors.forename: Xiao-Hua
authors.initials: XH
authors.lastname: Zhang
authors.affiliation: Beijing Institute of Functional Neurosurgery, Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, P.R. China.
authors.forename: Yun-Peng
authors.initials: YP
authors.lastname: Wang
authors.affiliation: Beijing Institute of Functional Neurosurgery, Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, P.R. China.
authors.forename: Ji-Ping
authors.initials: JP
authors.lastname: Li
authors.affiliation: Beijing Institute of Functional Neurosurgery, Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, P.R. China.
authors.forename: Yong-Jie
authors.initials: YJ
authors.lastname: Li
mesh_terms: D001007:Anxiety / Q000628:therapy; D001288:Attention; D003071:Cognition; D046690:Deep Brain Stimulation; D003863:Depression / Q000628:therapy; D056344:Executive Function; D005917:Globus Pallidus / Q000503:physiopathology*; D006801:Humans; D008570:Memory, Short-Term; D010300:Parkinson Disease / Q000628:therapy*; D011788:Quality of Life; D016032:Randomized Controlled Trials as Topic; D020531:Subthalamic Nucleus / Q000503:physiopathology*