title: Long-term Efficacy of Subthalamic Nucleus Deep Brain Stimulation in Parkinson's Disease: A 5-year Follow-up Study in China.
abstract: BACKGROUND
  Subthalamic nucleus deep brain stimulation (STN DBS) is effective against advanced Parkinson's disease (PD), allowing dramatic improvement of Parkinsonism, in addition to a significant reduction in medication. Here we aimed to investigate the long-term effect of STN DBS in Chinese PD patients, which has not been thoroughly studied in China.
  
  
  METHODS
  Ten PD patients were assessed before DBS and followed up 1, 3, and 5 years later using Unified Parkinson's Disease Rating Scale Part III (UPDRS III), Parkinson's Disease Questionnatire-39, Parkinson's Disease Sleep Scale-Chinese Version, Mini-mental State Examination, Montreal Cognitive Assessment, Hamilton Anxiety Scale and Hamilton Depression Scale. Stimulation parameters and drug dosages were recorded at each follow-up. Data were analyzed using the ANOVA for repeated measures.
  
  
  RESULTS
  In the "off" state (off medication), DBS improved UPDRS III scores by 35.87% in 5 years, compared with preoperative baseline (P < 0.001). In the "on" state (on medication), motor scores at 5 years were similar to the results of preoperative levodopa challenge test. The quality of life is improved by 58.18% (P < 0.001) from baseline to 3 years and gradually declined afterward. Sleep, cognition, and emotion were mostly unchanged. Levodopa equivalent daily dose was reduced from 660.4 ± 210.1 mg at baseline to 310.6 ± 158.4 mg at 5 years (by 52.96%, P < 0.001). The average pulse width, frequency and amplitude at 5 years were 75.0 ± 18.21 μs, 138.5 ± 19.34 Hz, and 2.68 ± 0.43 V, respectively.
  
  
  CONCLUSIONS
  STN DBS is an effective intervention for PD, although associated with a slightly diminished efficacy after 5 years. Compared with other studies, patients in our study required lower voltage and medication for satisfactory symptom control.
authors.forename: Lu-Lu
authors.initials: LL
authors.lastname: Jiang
authors.forename: Jin-Long
authors.initials: JL
authors.lastname: Liu
authors.forename: Xiao-Li
authors.initials: XL
authors.lastname: Fu
authors.forename: Wen-Biao
authors.initials: WB
authors.lastname: Xian
authors.forename: Jing
authors.initials: J
authors.lastname: Gu
authors.forename: Yan-Mei
authors.initials: YM
authors.lastname: Liu
authors.forename: Jing
authors.initials: J
authors.lastname: Ye
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.forename: Hao
authors.initials: H
authors.lastname: Qian
authors.forename: Shao-Hua
authors.initials: SH
authors.lastname: Xu
authors.forename: Zhong
authors.initials: Z
authors.lastname: Pei
authors.affiliation: Department of Neurology, First Affiliated Hospital, Sun Yat-sen University, Guangdong Key Laboratory for Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department, National Key Discipline, Guangzhou, Guangdong 510080, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Chen
mesh_terms: D000368:Aged; D002681:China; D046690:Deep Brain Stimulation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000628:therapy*; D011788:Quality of Life; D020531:Subthalamic Nucleus; D016896:Treatment Outcome