Objective: To evaluate clinical improvements in tremor following the implementation of adaptive deep brain stimulation (aDBS).

Background: Alpha-beta (8-30Hz) based aDBS is a safe and effective therapy for people with Parkinson’s disease (PD). However, beta-range local field potentials are primarily associated with bradykinesia and rigidity, with limited and conflicting correlations to tremor. Therefore, understanding the effect of aDBS in postural, action and resting tremor in PD may enhance clinical decision-making in aDBS programming.

Method: The impact of aDBS on tremor was assessed post-hoc from patients in the pivotal ADAPT-PD Trial (NCT04547712). Two modes of aDBS were evaluated with a single-blind randomized cross-over: single threshold (ST-aDBS, fast adapting over milliseconds) and dual threshold (DT-aDBS, slow adapting over minutes). In the full cohort, a tremor subscore was calculated (MDS-UPDRS III items 15-18; total 10 scores, range 0-40) during continuous (c)DBS and aDBS. To identify an enriched cohort with baseline clinically relevant tremor during cDBS, participants with tremor scores of ≥ 2 (indicating mild, moderate or severe) on the MDS-UPDRS questions 2.10 (in the worst condition) and 3.18 (in the OFF/off state) were identified. Changes in tremor scores from cDBS to aDBS were assessed in the full and enriched cohort.

Results: Sixty participants (mean [SD] age 61.1 [8.15] years; 41 [68.3%] male) with moderate to advanced PD completed aDBS evaluation (46 ST-aDBS and 55 DT-aDBS). There was a reduction in postural, action and resting tremor in the MDS-UPDRS III-tremor subscore during DT-aDBS compared to cDBS (0.9±2.83, P=0.01, effect size 0.32), but no difference on ST-aDBS compared to cDBS (0.0±3.18, P=0.79). The subgroup of participants with physician-rated constancy of tremor (rated ≥ 2 on MDS-UPDRS 3.18, n=41) demonstrated a decreased score on DT-aDBS (-1.2±3.1, P=0.02, effect size 0.38), but not ST-aDBS (-0.4±3.7, P>0.05). The subgroup of participants with self-rated tremor (rating of ≥ 2 MDS-UPDRS 2.10, n=20) demonstrated a decreased score on DT-aDBS (-2.2±3.1, P=0.003, effect side 0.69) but not ST-aDBS (-0.6±5.1, P>0.05).

Conclusion: We observed a significant reduction in all tremor topographies among PD patients treated with DT-aDBS compared to cDBS. In this cohort, the utilization of alpha-beta signal as a neurophysiological biomarker for aDBS was associated with greater tremor improvement compared to cDBS.

« Back to 2025 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/adaptive-deep-brain-stimulation-for-tremor-control-in-parkinsons-disease/