Congratulation to Drs. Aparna Wagle Shukla, Leonardo Almeida, Wei Hu, and Michael Okun on the publication of “A novel paradigm of variable frequency deep brain stimulation to improve freezing of gait in Parkinson’s disease,” which was published in the April 23rd edition of Neurology.
Objective: To determine the effects of a novel Deep brain stimulation (DBS) paradigm of combining high frequency DBS (HFS) and Low frequency DBS (LFS) in varying patterns (VFS) for freezing of gait (FOG) and appendicular motor symptoms in Parkinson’s disease (PD).
Background: DBS is a well-established therapy for PD and is conventionally delivered in a HFS (130–180 Hz). HFS DBS does not usually control axial symptoms such as FOG. LFS (60–80 Hz) is an alternate option, however the benefits maybe transient, inconsistent, and not alleviate appendicular motor symptoms.
Design/Methods: Twenty-eight PD subjects (16 males, 12 females) with bilateral STN DBS (PINS system) optimized on HFS for control of tremor, rigidity and bradykinesia were enrolled. Despite optimization, these patients complained of persistent FOG. Unified PD Rating Scale (UPDRS) and a 10 meter timed up and go (TUG) task were performed at baseline while patients were OFF medications OFF-DBS, one hour after HFS, one hour after LFS, one hour after VFS, and at six months after VFS programming. Repeated measures ANOVA and paired-t test were used.
Results: VFS improved UPDRS tremor score (35.3% improvement, p = 0.01), bradykinesia score (29.7% improvement, p = 0.01) and rigidity score (29.8% improvement, p = 0.01). VFS outcome measures at six months revealed persistent improvement (p > 0.05) compared to baseline. Total TUG time significantly improved with VFS when compared to HFS (39.4% improvement, p = 0.02) and LFS (43.7% improvement, p = 0.03). Similarly, the number of freezing episodes significantly reduced with VFS compared to HFS (85.6%, p = 0.03) and LFS (83.5%, p = 0.01).
Conclusions: VFS DBS is potentially effective for controlling freezing of gait and appendicular motor symptoms in PD compared to HFS and LFS, and the benefits remain sustained for six months. A larger follow-up study will further confirm these results.