Subthalamic nucleus versus globus pallidus internus deep brain stimulation in the treatment of dystonia: A systematic review and meta-analysis of safety and efficacy

Objective: This systematic review and meta-analysis aimed to compare the efficacy and safety of deep brain stimulation (DBS) targeting subthalamic nucleus (STN) versus the globus pallidus internus (GPI) in the treatment of dystonia. Methods: A comprehensive search strategy was implemented up to July 2024, across five databases, identifying studies relevant to STN-DBS and GPI-DBS in dystonia. Eligibility criteria included randomized controlled trials (RCTs) and observational studies comparing the two interventions. Two independent reviewers conducted the screening and data extraction. The risk of bias was assessed using RoB-2 for RCTs and the Newcastle-Ottawa Scale for cohort studies. Statistical analysis involved meta-analysis using Review Manager, with heterogeneity assessed by I2 and Chi-square tests. Subgroup and sensitivity analyses were performed. Results: Five studies, involving 154 patients, were included. No significant difference was found between STNDBS and GPI-DBS in Burke-Fahn-Marsden Dystonia Rating Scale motor and disability (BFMDRS-M and BFMDRS-D) scores at 1 months, 6 and 12 months. STN-DBS showed significant improvement in mental health (SMD = 0.43, 95 % CI: [0.05, 0.8], P = 0.03). STN-DBS also showed significant improvement in Hamilton Anxiety Rating Scale (HAMA) (SMD =-2.7, 95 % CI: [-5.38,-0.02], P = 0.05). No significant difference was found in Hamilton Depression Rating Scale (HAMD) scores. Conclusions: Both STN-DBS and GPI-DBS can improve motor symptoms in dystonia, with STN-DBS potentially resulting in more superior mental health benefits. Future research should address long-term outcomes, and regional effectiveness, and include diverse populations to enhance generalizability.