OBJECTIVE Deep brain stimulation (DBS) is effective in the management of patients with advanced Parkinson's disease(PD). While both the globus pallidus pars interna (GPi) and the subthalamic nucleus (STN) are accepted targets,their relative efficacy in randomized controlled trials (RCTs) has not been established beyond 12 months. The objectiveof this study was to conduct a meta-analysis of RCTs to compare outcomes among adults with PD undergoing DBS ofGPi or STN at various time points, including 36 months of follow-up.METHODS The MEDLINE, Embase, CENTRAL, Web of Science, and CINAHL databases were searched. Registriesfor clinical trials, selected conference proceedings, and the table of contents for selected journals were also searched.Screens were conducted independently and in duplicate. Among the 623 studies initially identified (615 through databasesearch, 7 through manual review of bibliographies, and 1 through a repeat screen of literature prior to submission), 19underwent full-text review; 13 of these were included in the quantitative meta-analysis. Data were extracted independentlyand in duplicate. The Cochrane Collaboration tool was used to assess the risk of bias. The GRADE evidenceprofile tool was used to assess the quality of the evidence. Motor scores, medication dosage reduction, activities of dailyliving, depression, dyskinesias, and adverse events were compared. The influence of disease duration (a priori) and theproportion of male patients within a study (post hoc) were explored as potential subgroups.RESULTS Thirteen studies (6 original cohorts) were identified. No difference in motor scores or activities of daily livingwas identified at 36 months. Medications were significantly reduced with STN stimulation (5 studies, weighted mean difference[WMD] -365.46, 95% CI -599.48 to -131.44, p = 0.002). Beck Depression Inventory scores were significantlybetter with GPi stimulation (3 studies; WMD 2.53, 95% CI 0.99-4.06 p = 0.001). The motor benefits of GPi and STN DBSfor PD are similar.CONCLUSIONS The motor benefits achieved with GPi and STN DBS for PD are similar. DBS of STN allows for agreater reduction of medication, but not as significant an advantage as DBS of GPi with respect to mood. This differenceis sustained at 36 months. Further long-term studies are necessary.
Deep brain stimulation (DBS) is the surgical procedure for patients with advanced Parkinson's disease. Globus pallidus internus (GPi) and subthalamic nucleus (STN) are the most targeted locations for the procedure. To investigate the variable efficiencies for the two different locations, we conducted a meta-analysis to compare both stimulation sites. MATERIALS AND METHODS: A systematic search was performed in PubMed, Embase, and the Cochrane Library databases. Randomized controlled trials comparing the efficacies of GPi and STN DBS were included. Clinical outcomes of motor function, nonmotor function, and quality of life (QOL) were collected for the meta-analysis. RESULTS: Ten eligible trials with 1,034 patients were included in the analysis. Unified Parkinson's disease rating scale III (UPDRS-III) scores were collected at 6, 12, and 24 months postsurgery separately to assess the motor function of the patients. A statistically significant effect in favor of the GPi DBS was obtained in the off-medication/on-stimulation phase of UPDRS-III at 12 months (mean difference [MD] =6.87, 95% confidence interval [95% CI]: 3.00-10.74, P=0.57, I (2)=0%). However, GPi DBS showed an opposite result at 24 months (MD =-2.46, 95% CI: -4.91 to -0.02, P=0.05, I (2)=0%). In the on-medication/on-stimulation phase, GPi DBS obtained a worse outcome compared with STN DBS (MD =-2.90, 95% CI: -5.71 to -0.09, P=0.05, I (2)=0%). Compared with STN DBS, increased dosage of levodopa equivalent doses was needed in GPi DBS (standardized MD =0.60, 95% CI: 0.46-0.74, P<0.00001, I (2)=24%). Meanwhile, Beck Depression Inventory II scores demonstrated that STN has a better performance (standardized MD =-0.31, 95% CI: -0.51 to -0.12, P=0.002, I (2)=0%). As for neurocognitive phase postsurgery, GPi DBS showed better performance in three of the nine tests, especially in verbal fluency. Use of GPi DBS was associated with a greater effect in eight of the nine subscales of QOL. CONCLUSION: GPi and STN DBS significantly improve advanced Parkinson's patients' symptoms, functionality, and QOL. Variable therapeutic efficiencies were observed in both procedures, GPi and STN DBS. GPi DBS allowed greater recovery of verbal fluency and provided greater relief of depression symptoms. Better QOL was also obtained using GPi DBS. Meanwhile, GPi DBS was also associated with increased dosage of levodopa equivalent doses. The question regarding which target is superior remained open for discussion. An understanding of the target selection still depends on individual symptoms, neurocognitive/mood status, therapeutic goals of DBS (eg, levodopa reduction), and surgical expertise.
Sleep-wake disturbances (SWD) are common nonmotor symptoms (NMS) and have a great impact on quality of life of patients with Parkinson's disease (PD). Deep brain stimulation (DBS) is an established treatment in PD. While the beneficial effects of DBS on cardinal PD motor symptoms are indisputable, the data for several NMS, including sleep-wake functions, are limited and often controversial. Our primary objective was to review the literature on the impact of DBS on sleep-wake functions in patients with PD. A systematic review of articles, published in PubMed between January 1st, 2000 and December 31st, 2015 was performed to identify studies addressing the evolution of sleep-wake functions after DBS in patients with PD. Only 38 of 208 studies, involving a total of 1443 subjects, met the inclusion criteria. Most of them reported a positive effect of subthalamic DBS on sleep quality and consequently on quality of life. Seven studies used polysomnography to objectively assess sleep parameters. The data concerning subthalamic DBS and wake functions are controversial and studies using objective, laboratory-based measures for the assessment of wake functions are lacking. Very few studies assessed the impact of other DBS targets (e.g. pallidal stimulation) on SWD. Further prospective observational DBS studies assessing subjectively and objectively specific sleep-wake parameters in patients with PD are needed.
OBJECTIVE Deep brain stimulation (DBS) is effective in the management of patients with advanced Parkinson's disease(PD). While both the globus pallidus pars interna (GPi) and the subthalamic nucleus (STN) are accepted targets,their relative efficacy in randomized controlled trials (RCTs) has not been established beyond 12 months. The objectiveof this study was to conduct a meta-analysis of RCTs to compare outcomes among adults with PD undergoing DBS ofGPi or STN at various time points, including 36 months of follow-up.METHODS The MEDLINE, Embase, CENTRAL, Web of Science, and CINAHL databases were searched. Registriesfor clinical trials, selected conference proceedings, and the table of contents for selected journals were also searched.Screens were conducted independently and in duplicate. Among the 623 studies initially identified (615 through databasesearch, 7 through manual review of bibliographies, and 1 through a repeat screen of literature prior to submission), 19underwent full-text review; 13 of these were included in the quantitative meta-analysis. Data were extracted independentlyand in duplicate. The Cochrane Collaboration tool was used to assess the risk of bias. The GRADE evidenceprofile tool was used to assess the quality of the evidence. Motor scores, medication dosage reduction, activities of dailyliving, depression, dyskinesias, and adverse events were compared. The influence of disease duration (a priori) and theproportion of male patients within a study (post hoc) were explored as potential subgroups.RESULTS Thirteen studies (6 original cohorts) were identified. No difference in motor scores or activities of daily livingwas identified at 36 months. Medications were significantly reduced with STN stimulation (5 studies, weighted mean difference[WMD] -365.46, 95% CI -599.48 to -131.44, p = 0.002). Beck Depression Inventory scores were significantlybetter with GPi stimulation (3 studies; WMD 2.53, 95% CI 0.99-4.06 p = 0.001). The motor benefits of GPi and STN DBSfor PD are similar.CONCLUSIONS The motor benefits achieved with GPi and STN DBS for PD are similar. DBS of STN allows for agreater reduction of medication, but not as significant an advantage as DBS of GPi with respect to mood. This differenceis sustained at 36 months. Further long-term studies are necessary.
Systematic Review Question»Systematic review of interventions
