title: Benefits of subthalamic stimulation for elderly parkinsonian patients aged 70 years or older.
abstract: OBJECTIVE
  Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an accepted treatment for advanced Parkinson disease (PD). However, there is general reluctance in considering this therapy for PD patients over age 70 years with limited supporting evidence. Present study investigates age impacts in STN-DBS outcomes, focusing particularly on the elderly patients.
  
  
  METHODS
  Seventy-two consecutive patients were divided into younger and elderly (n=16, cutoff age=70years) groups. Both groups were comparable in preoperative clinical severity, except the elderly exhibited a levodopa (LD) response (P<0.05) inferior to that of the younger. Improvements in drug-off/DBS-on Unified PD Rating Scale (UPDRS) scores and reduction in daily LD-equivalent dose (LED) after 6 months were evaluated relative to the presurgical drug-off baseline. Preoperative factors predictive of favorable surgical outcomes were analyzed using a multivariate linear regression model.
  
  
  RESULTS
  After DBS therapy, elderly patients exhibited clinical improvements particularly in the tremor (56%) and LD-induced dyskinesia (78%). Improvement of axial dysfunction (24%) and reduction of daily LED (24%) showed no intergroup difference. Adverse events, particularly dysarthria, occurred frequently in elderly group. The overall improvements in UPDRS scores were suboptimal in elderly group, correlating with their preoperative inferior LD responses. Elderly patients who presented predominantly with akinesia before surgery achieved superior surgical outcomes (adjusted R(2)=0.657, P<0.001).
  
  
  CONCLUSIONS
  STN-DBS therapy is beneficial to some elderly PD patients aged 70 years or older. Tremor, axial dysfunctions and drug-induced dyskinesia are the main indications for the elderly; however, their clinical benefits are inferior to those of younger patients.
authors: Department of Neurosurgery, China Medical University Hospital, Taichung, Taiwan. Electronic address: tsmchiou@pchome.com.tw.
authors: Shang-Ming
authors: SM
authors: Chiou
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000008:administration & dosage / Q000009:adverse effects; D046690:Deep Brain Stimulation / Q000379:methods*; D004409:Dyskinesia, Drug-Induced / Q000209:etiology / Q000628:therapy*; D005260:Female; D006801:Humans; D007980:Levodopa / Q000008:administration & dosage / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010300:Parkinson Disease / Q000150:complications / Q000628:therapy*; D020531:Subthalamic Nucleus; D014202:Tremor / Q000209:etiology / Q000628:therapy*
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa
keywords: Age; Deep brain stimulation; Parkinson disease; Prognosis; Subthalamic nucleus