Category: Parkinson’s Disease: Clinical Trials
Objective: First, we aimed to evaluate the optimal contact to address axial symptoms with low frequency deep brain stimulation (LFS). Second, we aimed to evaluate the effects of LFS on the symptoms over time. Third, we aimed to group patients depending on their type of response to LFS and to identify markers of these groups.
Background: Axial symptoms such as deficits of gait and balance, freezing of gait (FoG), and speech disorders are commonly reported as among the most impairing aspects of PD after DBS implantation [1]. Low frequency stimulation (LFS, 60-80Hz) has been suggested to be more suitable to address these symptoms than standard high-frequency stimulation (HFS, 130Hz) [2]. However, despite few prelimi-nary studies on this topic, key aspects of LFS remain unclear: First, the effects of LFS have been reported to vary among patients and over time. Second, the optimal stimulation contacts may differ for LFS and HFS.
A clear characterization of the specificity and dynamical effects of LFS and HFS is critical to tailor stimulation to various patient phenotypes, and to support the development of adaptative DBS protocols able to dynamically combine the advantages of both HFS and LFS [3].
Method: We stimulated condition-blinded PD patients with unilateral monopolar LFS and immediately evaluated axial symptoms. We then evaluated the effect of the identified optimal LFS contact over time, immediately after turning stimulation ON, after 20 minutes, one hour and one day. For each of these conditions, patients performed a battery of tasks that measured gait performance, both during straight walking and turning, balance, FoG and speech. We quantified changes induced by stimulation in key kinematic parameters, ground reaction forces, and number and duration of freezing episodes.
Results: We observed changes in balance, speech and gait parameters that were patient-specific and time-varying for each of the tested conditions.
Conclusion: These results point out the importance to comprehensively characterize the effect of DBS frequency over time, and to consider patient-specificities in the development of closed-loop therapies.
References: [1] A. Collomb-Clerc et M.-L. Welter, « Effects of deep brain stimulation on balance and gait in patients with Parkinson’s disease: A systematic neurophysiological review », Neurophysiol. Clin. Neurophysiol., vol. 45, no 4, p. 371‑388, nov. 2015, doi: 10.1016/j.neucli.2015.07.001.
[2] D. Su et al., « Frequency-dependent effects of subthalamic deep brain stimulation on motor symptoms in Parkinson’s disease: a meta-analysis of controlled trials », Sci. Rep., vol. 8, sept. 2018, doi: 10.1038/s41598-018-32161-3.
[3] H. M. Bronte-Stewart et al., « Perspective: Evolution of Control Variables and Policies for Closed-Loop Deep Brain Stimulation for Parkinson’s Disease Using Bidirectional Deep-Brain-Computer Interfaces », Front. Hum. Neurosci., vol. 14, 2020, https://www.frontiersin.org/article/10.3389/fnhum.2020.00353
To cite this abstract in AMA style:
Y. Thenaisie, L. Comeliau, C. Varescon, L. Asboth, M. Castro, J. Bally, G. Courtine, J. Bloch, E. Martin Moraud. Dynamical modulations of low frequency deep brain stimulation on axial symptoms in Parkinson’s disease [abstract]. Mov Disord. 2022; 37 (suppl 2). https://www.mdsabstracts.org/abstract/dynamical-modulations-of-low-frequency-deep-brain-stimulation-on-axial-symptoms-in-parkinsons-disease/. Accessed November 21, 2024.« Back to 2022 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/dynamical-modulations-of-low-frequency-deep-brain-stimulation-on-axial-symptoms-in-parkinsons-disease/