STN versus GPi deep brain stimulation for dyskinesia improvement in advanced Parkinson's disease: A meta-analysis of randomized controlled trials

Background: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) and the globus pallidus internus (GPi) are currently the most common and effective surgical targets for advanced Parkinson's disease (APD). Herein, we conducted a meta-analysis to evaluate the comprehensive efficacy of STN-DBS and GPi-DBS in patients with APD. Methods: We conducted a systematic search for relevant articles written in English in the Cochrane Library, PubMed, and EMBASE databases through January 2020. Studies comparing the efficacy and clinical outcomes of GPi-DBS and STN-DBS for APD were included and analyzed. Results: Ten eligible trials with a total of 857 patients were included in this meta-analysis. The results showed no significant difference between the STN-DBS and GPi-DBS groups in Unified Parkinson's Disease Rating Scale (UPDRS) III scores during the on and off-medication phases(SMD, 0.1; 95 % CI,-0.04 to 0.25; p = 0.17, on-med), (SMD, -0.12;95 % CI-0.37 to 0.13, p = 0.33,off-med). Dyskinesia scores and the activities of daily living (ADLs) scores during the on-medication phase showed significant differences in favor of GPi stimulation (SMD, 0.16; 95 % CI, 0.01-0.32; P < 0.05)/(SMD, 0.18; 95 % CI, 0.01-0.34; P < 0.05). The ADLs score during the off-medication phase showed no significant difference between the STN-DBS and GPi-DBS groups (SMD,-0.11; 95 % CI, 0.32-0.11; P = 0.33). The LED showed significant differences in favor of STN stimulation (SMD, -0.57; 95 % CI, 0.74-0.40; P < 0.00001). Conclusions: Both STN and GPi-DBS were equally effective in improving motor dysfunction. STN-DBS was superior for medication reduction, whereas GPi-DBS perhaps led to less dyskinesia and improved the postoperative ADLs (on-medication) in APD patients. Hence, the goals of DBS can be important in the target selection. More studies comparing the adverse events and quality of life between the two targets are needed.

Automated summary

Both STN and GPi-DBS were equally effective in improving motor dysfunction in patients with APD. However, STN-DBS showed superiority in reducing medication usage, while GPi-DBS may lead to less dyskinesia and improved activities of daily living. Further studies comparing adverse events and quality of life between these two targets are needed.