Medication dose reductions after pallidal versus subthalamic stimulation in patients with Parkinson's disease.
OBJECTIVE
To compare the medication dose reduction between deep brain stimulation (DBS) of the globus pallidus interna (GPi) vs subthalamic nucleus (STN) in matched patients with Parkinson's disease (PD).


METHODS
Records of 12 patients with PD who underwent GPi-DBS at our institution from 2002 to 2008 were matched by pre-operative PD medication doses and pre-operative motor Unified Parkinson's Disease Rating Scale (UPDRS) scores to 12 cases of STN-DBS. PD medication doses were converted to levodopa equivalent doses (LEDs).


RESULTS
GPi and STN groups had similar mean pre-operative LEDs and motor UPDRS scores. At 6 months post-DBS, there was no significant difference in percent reduction in LEDs between the GPi (47.95%) and STN (37.47%) groups (P = 0.52). The mean post-operative 'medication off/stimulation on' motor UPDRS scores did not differ significantly between GPi (15.33) and STN (16.25) groups (P = 0.74). The mean percent reduction in motor UPDRS scores was also similar between GPi (58.44%) and STN (58.98%) patients (P = 0.94).


CONCLUSIONS
We conclude that in disease-matched patients with PD undergoing DBS, both GPi and STN may result in similar reduction in PD medication doses.
Department of Neurology Department of Neurological Surgery, Mayo Clinic Arizona, Scottsdale, AZ 85259, USA. evidente.virgilio@mayo.edu
V G H
VG
Evidente
A P
AP
Premkumar
C H
CH
Adler
J N
JN
Caviness
E
E
Driver-Dunckley
M K
MK
Lyons
D000368:Aged; D000978:Antiparkinson Agents / Q000008:administration & dosage; D046690:Deep Brain Stimulation / Q000379:methods / Q000706:statistics & numerical data*; D005917:Globus Pallidus / Q000502:physiology*; D006801:Humans; D007980:Levodopa / Q000008:administration & dosage*; D008137:Longitudinal Studies; D008875:Middle Aged; D009434:Neural Pathways / Q000187:drug effects / Q000503:physiopathology / Q000601:surgery; D010300:Parkinson Disease / Q000188:drug therapy* / Q000503:physiopathology / Q000601:surgery*; D012189:Retrospective Studies; D020531:Subthalamic Nucleus / Q000502:physiology*; D013995:Time; D016896:Treatment Outcome
D000978:Antiparkinson Agents; D007980:Levodopa