Subthalamic and pallidal deep brain stimulation for Parkinson’s disease—meta-analysis of outcomes

Abstract

Although deep brain stimulation (DBS) of the globus pallidus internus (GPi) and the subthalamic nucleus (STN) has become an established treatment for Parkinson’s disease (PD), a recent meta-analysis of outcomes is lacking. To address this gap, we performed a meta-analysis of bilateral STN- and GPi-DBS studies published from 1990-08/2019. Studies with ≥10 subjects reporting Unified Parkinson’s Disease Rating Scale (UPDRS) III motor scores at baseline and 6–12 months follow-up were included. Several outcome variables were analyzed and adverse events (AE) were summarized. 39 STN studies (2035 subjects) and 5 GPi studies (292 subjects) were eligible. UPDRS-II score after surgery in the stimulation-ON/medication-OFF state compared to preoperative medication-OFF state improved by 47% with STN-DBS and 18.5% with GPi-DBS. UPDRS-III score improved by 50.5% with STN-DBS and 29.8% with GPi-DBS. STN-DBS improved dyskinesia by 64%, daily OFF time by 69.1%, and quality of life measured by PDQ-39 by 22.2%, while Levodopa Equivalent Daily Dose (LEDD) was reduced by 50.0%. For GPi-DBS information regarding dyskinesia, OFF time, PDQ-39 and LEDD was insufficient for further analysis. Correlation analysis showed that preoperative L-dopa responsiveness was highly predictive of the STN-DBS motor outcome across all studies. Most common surgery-related AE were infection (5.1%) and intracranial hemorrhage (3.1%). Despite a series of technological advances, outcomes of modern surgery are still comparable with those of the early days of DBS. Recent changes in target selection with a preference of GPi in elderly patients with cognitive deficits and more psychiatric comorbidities require more published data for validation.

How Does Deep Brain Stimulation Change the Course of Parkinson's Disease?

“…Two additional trials compared GPi‐DBS and STN‐DBS without a BMT arm and found no differences in changes of primary outcome measures 16,17 . However, both showed greater levodopa equivalent dose reductions and one showed greater improvements in off medication motor functioning with STN‐DBS, 16 findings that were confirmed by a recent large meta‐analysis 18 . Based on this solid evidence STN‐DBS and GPi‐DBS are firmly established treatment modalities to improve motor fluctuations and dyskinesias in advanced PD 19 .…”

“…16,17 However, both showed greater levodopa equivalent dose reductions and one showed greater improvements in off medication motor functioning with STN-DBS, 16 findings that were confirmed by a recent large meta-analysis. 18 Based on this solid evidence STN-DBS and GPi-DBS are firmly established treatment modalities to improve motor fluctuations and dyskinesias in advanced PD. 19 STN-DBS is also highly efficacious in reducing or even abolishing drug refractory PD tremor and is widely used in clinical practice for this indication.…”

Caregiver Burden in Partners of Parkinsonian Patients with Deep Brain Stimulation

“…The globus pallidus internus (Gpi) is an alternative DBS target for PD patients besides STN implantation as the Gpi is supposed to have a lower risk of dysarthria, neuropsychiatric complications and impaired cognition [ 61 ]. The discussion of the favorable target in PD is still controversial [ 61 ]. There is also scarce information on caregiver burden in Gpi patients [ 31 , 62 ].…”

A Review on Response to Device-Aided Therapies Used in Monogenic Parkinsonism and GBA Variants Carriers: A Need for Guidelines and Comparative Studies

“…On the other hand, although it seems relatively safe concerning cognitive function, chronic stimulation of STN has been associated with a subtle decline in cognitive domains, exceptionally verbal fluency, and executive function [90,91]. Despite little data is supporting that STN-DBS has a worse cognitive outcome than GPi-DBS [92], more published information is required for validation [93]; if there is significant concern about cognitive decline, particularly regarding verbal fluency, processing speed, and working memory in a patient undergoing DBS, GPi has been recommended [84,89].…”