Pilot study assessing the feasibility of applying bilateral subthalamic nucleus deep brain stimulation in very early stage Parkinson's disease: study design and rationale.
BACKGROUND
Deep brain stimulation provides significant symptomatic benefit for people with advanced Parkinson's disease whose symptoms are no longer adequately controlled with medication. Preliminary evidence suggests that subthalamic nucleus stimulation may also be efficacious in early Parkinson's disease, and results of animal studies suggest that it may spare dopaminergic neurons in the substantia nigra.


OBJECTIVE
We report the methodology and design of a novel Phase I clinical trial testing the safety and tolerability of deep brain stimulation in early Parkinson's disease and discuss previous failed attempts at neuroprotection.


METHODS
We recently conducted a prospective, randomized, parallel-group, single-blind pilot clinical trial of deep brain stimulation in early Parkinson's disease. Subjects were randomized to receive either optimal drug therapy or deep brain stimulation plus optimal drug therapy. Follow-up visits occurred every six months for a period of two years and included week-long therapy washouts.


RESULTS
Thirty subjects with Hoehn & Yahr Stage II idiopathic Parkinson's disease were enrolled over a period of 32 months. Twenty-nine subjects completed all follow-up visits; one patient in the optimal drug therapy group withdrew from the study after baseline. Baseline characteristics for all thirty patients were not significantly different.


CONCLUSIONS
This study demonstrates that it is possible to recruit and retain subjects in a clinical trial testing deep brain stimulation in early Parkinson's disease. The results of this trial will be used to support the design of a Phase III, multicenter trial investigating the efficacy of deep brain stimulation in early Parkinson's disease.
Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA. david.charles@vanderbilt.edu
David
D
Charles
Christopher
C
Tolleson
Thomas L
TL
Davis
Chandler E
CE
Gill
Anna L
AL
Molinari
Mark J
MJ
Bliton
Michael G
MG
Tramontana
Ronald M
RM
Salomon
Chris
C
Kao
Lily
L
Wang
Peter
P
Hedera
Fenna T
FT
Phibbs
Joseph S
JS
Neimat
Peter E
PE
Konrad
D000368:Aged; D046690:Deep Brain Stimulation; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010300:Parkinson Disease / Q000628:therapy*; D010865:Pilot Projects; D012107:Research Design; D016037:Single-Blind Method; D020531:Subthalamic Nucleus / Q000502:physiology*; D013997:Time Factors