Pallidal versus subthalamic deep-brain stimulation for Parkinson's disease.
BACKGROUND
Deep-brain stimulation is the surgical procedure of choice for patients with advanced Parkinson's disease. The globus pallidus interna and the subthalamic nucleus are accepted targets for this procedure. We compared 24-month outcomes for patients who had undergone bilateral stimulation of the globus pallidus interna (pallidal stimulation) or subthalamic nucleus (subthalamic stimulation).


METHODS
At seven Veterans Affairs and six university hospitals, we randomly assigned 299 patients with idiopathic Parkinson's disease to undergo either pallidal stimulation (152 patients) or subthalamic stimulation (147 patients). The primary outcome was the change in motor function, as blindly assessed on the Unified Parkinson's Disease Rating Scale, part III (UPDRS-III), while patients were receiving stimulation but not receiving antiparkinsonian medication. Secondary outcomes included self-reported function, quality of life, neurocognitive function, and adverse events.


RESULTS
Mean changes in the primary outcome did not differ significantly between the two study groups (P=0.50). There was also no significant difference in self-reported function. Patients undergoing subthalamic stimulation required a lower dose of dopaminergic agents than did those undergoing pallidal stimulation (P=0.02). One component of processing speed (visuomotor) declined more after subthalamic stimulation than after pallidal stimulation (P=0.03). The level of depression worsened after subthalamic stimulation and improved after pallidal stimulation (P=0.02). Serious adverse events occurred in 51% of patients undergoing pallidal stimulation and in 56% of those undergoing subthalamic stimulation, with no significant between-group differences at 24 months.


CONCLUSIONS
Patients with Parkinson's disease had similar improvement in motor function after either pallidal or subthalamic stimulation. Nonmotor factors may reasonably be included in the selection of surgical target for deep-brain stimulation. (ClinicalTrials.gov numbers, NCT00056563 and NCT01076452.)
Iowa City Veterans Affairs Medical Center, Iowa City, USA.
Kenneth A
KA
Follett
Frances M
FM
Weaver
Matthew
M
Stern
Kwan
K
Hur
Crystal L
CL
Harris
Ping
P
Luo
William J
WJ
Marks
Johannes
J
Rothlind
Oren
O
Sagher
Claudia
C
Moy
Rajesh
R
Pahwa
Kim
K
Burchiel
Penelope
P
Hogarth
Eugene C
EC
Lai
John E
JE
Duda
Kathryn
K
Holloway
Ali
A
Samii
Stacy
S
Horn
Jeff M
JM
Bronstein
Gatana
G
Stoner
Philip A
PA
Starr
Richard
R
Simpson
Gordon
G
Baltuch
Antonio
A
De Salles
Grant D
GD
Huang
Domenic J
DJ
Reda
D000203:Activities of Daily Living; D000368:Aged; D003071:Cognition; D004599:Electric Stimulation Therapy / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D005917:Globus Pallidus; D006801:Humans; D057194:Intention to Treat Analysis; D008297:Male; D008875:Middle Aged; D009048:Motor Skills; D010300:Parkinson Disease / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D011788:Quality of Life; D020531:Subthalamic Nucleus; D016896:Treatment Outcome