Differentiating effects of levodopa and subthalamic nucleus deep brain stimulation on motor features in Parkinson disease - Research summary

Q: How did the study compare levodopa and STN DBS effects on motor symptoms?

UPDRS-III was assessed in three conditions: preoperative OFF medication, preoperative ON medication, and postoperative ON-DBS/OFF medication. Exploratory factor analysis then defined a consensus motor symptom structure across conditions to compare treatment responses by factor.

Q: Which motor features showed relatively greater improvement with STN DBS versus levodopa?

STN DBS showed slightly superior efficacy for upper body tremor, while levodopa demonstrated much greater effectiveness for axial symptoms and higher effectiveness for lower body tremor and lower body bradykinesia.

Q: What does the weak correlation between treatment responses imply for selecting therapy?

Although the treatments have similar but distinct therapeutic profiles, weak correlations across modalities challenge using levodopa responsiveness to predict DBS outcomes. The findings support individualizing treatment selection based on the patient’s symptom profile.

Sep 30, 2026

Uploaded by James

Differentiating effects of levodopa and subthalamic nucleus deep brain stimulation (STN DBS) on parkinsonian motor components was systematically evaluated to clarify which symptoms may respond more effectively to each therapy. A retrospective cohort of 395 Parkinson disease patients receiving bilateral STN DBS (1999–2020) compared UPDRS-III in preoperative OFF and ON medication states and postoperative ON-DBS/OFF medication. Exploratory factor analysis supported a consensus symptom structure across conditions, and factor-wise responses were tested with Wilcoxon rank-sum methods and Kendall’s tau correlations. Both treatments improved all motor features, with STN DBS favoring upper body tremor and levodopa showing greater benefits for axial symptoms and specific lower body manifestations. Despite these differences, response correlations across modalities were weak yet significant for selected domains.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages7

Reading Time18 min

AccessFree to download

Introduction

Methods

Results

Conclusion

PRDOA 14 (2026) 100417 Contents lists available at ScienceDirect Clinical Parkinsonism & Related Disorders journal [homepage:](homepage: www.sciencedirect.com/journal/clinical-parkinsonism-and-related-disorders)[ www.sciencedirect.com/journal/clinical-parkinsonism-and-related-disorders](homepage: www.sciencedirect.com/journal/clinical-parkinsonism-and-related-disorders) | Differentiating effects of levodopa and subthalamic nucleus deep brain stimulation on motor features in Parkinson disease
Tiffanie A. Lee a, Deepa Ramesha, Mwiza Ushe b, Scott A. Norris b,c, Samer D. Tabbal b,1, Joel S. Perlmutter b,c,d , John R. Youncea,*
a University of North Carolina at Chapel Hill, Department of Neurology, 170 Manning Drive, Chapel Hill, NC 27599, USA b Washington University in St Louis, Department of Neurology, 660 South Euclid Avenue, St Louis, MO 63110, USAc Washington University in St Louis, Department of Radiology, St Louis, MO, USA
d Washington University in St Louis, Departments of Neuroscience, Physical Therapy, Occupational Therapy, St Louis, MO, USA | | | | --- | --- | --- | | A R T I C L E I N F O | | A B S T R A C T | | Keywords:
Parkinson disease Deep brain stimulation Levodopa
Factor analysis | | Introduction: While deep brain stimulation of the subthalamic nucleus (STN DBS) is traditionally used to treat motor fluctuations in Parkinson disease (PD), recent progress in levodopa delivery systems may offer noninvasive alternatives to surgical options. To gain insight into symptoms more likely to be treated effectively by STN DBS or levodopa, we systematically compared the differential effects of levodopa and STN-DBS on specific parkinsonian motor components.
Methods: We retrospectively analyzed 395 PD patients who received bilateral STN-DBS at Washington University (1999–2020). UPDRS-III was obtained in three conditions: preoperative OFF-medication, preoperative ONmedication, and postoperative ON-DBS/OFF-medication. Exploratory factor analysis identified a consensus structure across conditions. Treatment responses by factor were compared using Wilcoxon rank-sum tests and correlations were assessed with Kendall’s tau.
Results: Both treatments significantly improved all motor features. STN-DBS showed slightly superior efficacy for upper body tremor (mean change: − 3.84 vs − 3.43, p < 0.001), while levodopa demonstrated much greater effectiveness for axial symptoms ( − 5.41 vs − 2.65, p < 0.001), and slightly greater effectiveness for lower body tremor ( − 1.25 vs − 1.06, p < 0.001), and lower body bradykinesia ( − 1.18 vs − 0.91, p = 0.005). Correlations between treatment responses were weak but statistically significant for rigidity (τ = 0.158), bradykinesia (hand:τ = 0.118; leg: τ = 0.179), and axial symptoms (τ = 0.207).
Conclusion: Levodopa and STN-DBS demonstrate similar but distinct therapeutic profiles across parkinsonian motor domains. However, weak correlations between treatment modalities for all motor features challenge the utility of levodopa responsiveness for DBS candidacy and support individualization of treatment selection based on symptom profile. | 1. Introduction Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an established adjunctive therapy for the treatment of motor symptoms of Parkinson disease (PD), often used when oral medications fail to adequately treat features such as motor fluctuations, tremor, and dyskinesia [1,2]. Initially, response of motor symptoms to an oral levodopa challenge was considered the best predictor of response to STNDBS, with early studies demonstrating strong correlations between magnitude of DBS response and levodopa response [3,4]. This relationship formed the foundation for patient selection criteria, with a sufficient response to oral levodopa challenge serving as a key determinant of STN DBS candidacy [2]. However, more recent studies have revealed weaker and more variable relationships between response to levodopa c

FAQs

How did the study compare levodopa and STN DBS effects on motor symptoms?

UPDRS-III was assessed in three conditions: preoperative OFF medication, preoperative ON medication, and postoperative ON-DBS/OFF medication. Exploratory factor analysis then defined a consensus motor symptom structure across conditions to compare treatment responses by factor.

Which motor features showed relatively greater improvement with STN DBS versus levodopa?

STN DBS showed slightly superior efficacy for upper body tremor, while levodopa demonstrated much greater effectiveness for axial symptoms and higher effectiveness for lower body tremor and lower body bradykinesia.

What does the weak correlation between treatment responses imply for selecting therapy?

Although the treatments have similar but distinct therapeutic profiles, weak correlations across modalities challenge using levodopa responsiveness to predict DBS outcomes. The findings support individualizing treatment selection based on the patient’s symptom profile.

Sep 30, 2026

Uploaded by James