Selective use of low frequency stimulation in Parkinson's disease based on absence of tremor.
BACKGROUND
High frequency stimulation (HFS) of the subthalamic nucleus is one of the most effective treatments for advanced Parkinson's disease (PD). HFS has provided beneficial improvements in the cardinal features of PD, but has not been proven as effective for addressing the axial predominant levodopa resistant symptoms, such as speech disturbances, gait disturbances, and postural instability. Recent studies have suggested that changes in stimulation parameters may influence differing PD symptoms.


OBJECTIVE
The purpose of this study was to compare the effects of low frequency stimulation (LFS) versus HFS on the Unified Parkinson's Disease Rating Scale (UPDRS), gait, balance, and verbal fluency.


METHODS
Eight tremor dominant and nine non-tremor dominant participants with bilateral deep brain stimulation of the subthalamic nucleus were tested off stimulation, during LFS, and during HFS.


RESULTS
Results revealed that HFS significantly reduced UPDRS tremor score in the tremor dominant group; however no differences emerged within the non-tremor dominant group. No differences between groups or stimulation conditions were found for gait, balance, and verbal fluency measures.


CONCLUSIONS
These results may suggest that HFS is better than LFS for reducing tremor in tremor dominant patients. However, patients with mild or no tremor show no acute differences in benefit from LFS as compared to HFS.
Department of Applied Physiology and Kinesiology and Center for Movement Disorders & Neurorestoration, University of Florida, Gainesville, FL, USA.
Elizabeth L
EL
Stegemöller
Srikant
S
Vallabhajosula
Ihtsham
I
Haq
Nelson
N
Hwynn
Chris J
CJ
Hass
Michael S
MS
Okun
D000328:Adult; D000368:Aged; D046690:Deep Brain Stimulation / Q000379:methods*; D005260:Female; D005684:Gait; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000628:therapy*; D004856:Postural Balance; D014202:Tremor / Q000503:physiopathology*; D014705:Verbal Behavior
Low frequency stimulation; Parkinson's disease; balance; gait; speech