Cognitive and Psychiatric Effects of STN versus GPi Deep Brain Stimulation in Parkinson's Disease: A Meta-Analysis of Randomized Controlled Trials

Abstract

BackgroundDeep brain stimulation (DBS) of either the subthalamic nucleus (STN) or the globus pallidus interna (GPi) can reduce motor symptoms in patients with Parkinson’s disease (PD) and improve their quality of life. However, the effects of STN DBS and GPi DBS on cognitive functions and their psychiatric effects remain controversial. The present meta-analysis was therefore performed to clarify these issues.MethodsWe searched the PUBMED, EMBASE, and the Cochrane Central Register of Controlled Trials databases. Other sources, including internet-based clinical trial registries and grey literature sources, were also searched. After searching the literature, two investigators independently performed literature screens to assess the quality of the included trials and to extract the data. The outcomes included the effects of STN DBS and GPi DBS on multiple cognitive domains, depression, anxiety, and quality of life.ResultsSeven articles related to four randomized controlled trials that included 521 participants were incorporated into the present meta-analysis. Compared with GPi DBS, STN DBS was associated with declines in selected cognitive domains after surgery, including attention, working memory and processing speed, phonemic fluency, learning and memory, and global cognition. However, there were no significant differences in terms of quality of life or psychiatric effects, such as depression and anxiety, between the two groups.ConclusionsA selective decline in frontal-subcortical cognitive functions is observed after STN DBS in comparison with GPi DBS, which should not be ignored in the target selection for DBS treatment in PD patients. In addition, compared to GPi DBS, STN DBS does not affect depression, anxiety, and quality of life.

Deep brain stimulation in the caudal zona incerta in patients with essential tremor: effects on cognition 1 year after surgery

“…Decline in verbal fluency has previously been reported following STN DBS and globus pallidus internus DBS in patients with Parkinson's disease, which has been described in a rather comprehensive meta review. 46 Decline in verbal fluency has also been reported after VIM DBS in ET, as mentioned previously. 14,16,33,44 So far there is no consensus as to what causes this deterioration.…”

Subcortical Intermittent Theta-Burst Stimulation (iTBS) Increases Theta-Power in Dorsolateral Prefrontal Cortex (DLPFC)

“…Svenningsson et al, 2012;Duncan et al, 2014;Manza et al, 2017). Medical treatments fail to improve cognitive symptoms in many patients (Svenningsson et al, 2012), and cognitive outcomes following conventional high-frequency DBS are mixed (Okun et al, 2009;Combs et al, 2015;Wang et al, 2016), with a recent meta-analysis finding that STN-DBS patients experienced decrements in multiple cognitive domains compared to medically-treated controls (Cernera et al, 2019). Ideally, nextgeneration therapies would address both motor and cognitive aspects of the disease, but will likely require alternative patterns of stimulation.…”

Current treatment of behavioral and cognitive symptoms of Parkinson's disease

“…As for effects of DBS on cognitive outcomes, a recent meta-analyses of randomized controlled trials [167] showed that STN stimulation, as compared to internal pallidal stimulation (GPi DBS), was associated with subtle declines predominantly in attention, working memory and processing speed, phonemic fluency and learning, and memory; however, there were no significant differences in terms of quality of life. A systematic review and meta-analysis [168] demonstrated decreased performance only in the Stroop color-naming test in the STN DBS vs. GPi DBS.…”