Randomized trial of deep brain stimulation for Parkinson disease: thirty-six-month outcomes.
OBJECTIVE
Our objective was to compare long-term outcomes of deep brain stimulation (DBS) of the globus pallidus interna (GPi) and subthalamic nucleus (STN) for patients with Parkinson disease (PD) in a multicenter randomized controlled trial.


METHODS
Patients randomly assigned to GPi (n = 89) or STN DBS (n = 70) were followed for 36 months. The primary outcome was motor function on stimulation/off medication using the Unified Parkinson's Disease Rating Scale motor subscale. Secondary outcomes included quality of life and neurocognitive function.


RESULTS
Motor function improved between baseline and 36 months for GPi (41.1 to 27.1; 95% confidence interval [CI] -16.4 to -10.8; p < 0.001) and STN (42.5 to 29.7; 95% CI -15.8 to -9.4; p < 0.001); improvements were similar between targets and stable over time (p = 0.59). Health-related quality of life improved at 6 months on all subscales (all p values significant), but improvement diminished over time. Mattis Dementia Rating Scale scores declined faster for STN than GPi patients (p = 0.01); other neurocognitive measures showed gradual decline overall.


CONCLUSIONS
The beneficial effect of DBS on motor function was stable and comparable by target over 36 months. Slight declines in quality of life following initial gains and gradual decline in neurocognitive function likely reflect underlying disease progression and highlight the importance of nonmotor symptoms in determining quality of life.


METHODS
This study provides Class III evidence that improvement of motor symptoms of PD by DBS remains stable over 3 years and does not differ by surgical target. Neurology® 2012;79:55-65.
Center for Management of Complex Chronic Care, Hines VA Hospital, Hines, IL, USA.Frances.Weaver@va.gov
Frances M
FM
Weaver
Kenneth A
KA
Follett
Matthew
M
Stern
Ping
P
Luo
Crystal L
CL
Harris
Kwan
K
Hur
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
D000368:Aged; D046690:Deep Brain Stimulation / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009048:Motor Skills / Q000502:physiology; D010300:Parkinson Disease / Q000503:physiopathology* / Q000523:psychology / Q000628:therapy*; D011446:Prospective Studies; D011788:Quality of Life / Q000523:psychology; D016037:Single-Blind Method; D016896:Treatment Outcome