Objective: To assess the impact of deep brain stimulation (DBS) target and Parkinson’s disease (PD) motor subtype on the total levodopa equivalent daily dose (LEDD) following surgery.
Background: DBS is an effective therapy for patients with PD and refractory motor complications. The globus pallidus interna (GPi) and the subthalamic nucleus (STN) are the most common targets for DBS implantation. Although early randomized studies found these targets to be equally efficacious, STN DBS is preferred given its association with a greater reduction in LEDD. The impact of DBS on LEDD long term and with relation to the PD phenotype remains incompletely investigated.
Method: A retrospective study of PD patients who were implanted with bilateral GPi or STN DBS from 2003 to 2019 and satisfied our inclusion criteria was conducted. Data including demographics, DBS surgery data, LEDD and the Unified Parkinson’s Disease Rating Scale Part III (UPDRS) was recorded. The UPDRS was used to categorize subjects into two motor phenotypes – tremor dominant (TD) and non-TD PD. LEDD up to 5 years post-DBS implantation were collected. A general linear model with repeated measures to analyze the relation between LEDD, DBS target and motor phenotype was performed using SPSS v28.0.1.1(14).
Results: Clinical data from 95 patients (21 TD and 74 non-TD) was analyzed. No significant impact of motor phenotype (p = 0.533) or time (p = 0.06) on LEDD changes after DBS up to 5 years of follow up was noted. However, patients with STN DBS implantation (n=45) showed greater reduction in LEDD (235+/- 11) compared to GPi DBS implantation (35+/-3) (p = 0.04). We found that LEDD decreases in a fashion that changes constantly rather than a linear trend after DBS (p = 0.01).
Conclusion: Bilateral STN DBS is associated with a greater medication decrease and LEDD decreases in a nonlinear fashion after DBS.
To cite this abstract in AMA style:
T. Mehta, V. Lavu, C. Hess, A. Ramirez-Zamora, M. Okun, J. Wong. Unraveling the Intertwined Relationship of DBS, Parkinson’s Disease Subtype and LEDD: A Retrospective Study [abstract]. Mov Disord. 2025; 40 (suppl 1). https://www.mdsabstracts.org/abstract/unraveling-the-intertwined-relationship-of-dbs-parkinsons-disease-subtype-and-ledd-a-retrospective-study/. Accessed November 20, 2025.« Back to 2025 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/unraveling-the-intertwined-relationship-of-dbs-parkinsons-disease-subtype-and-ledd-a-retrospective-study/