Comparative efficacy and safety of GPi-DBS versus STN-DBS in Meige syndrome: a retrospective propensity score-matched cohort study

BACKGROUND: Although deep brain stimulation (DBS) targeting the globus pallidus internus (GPi) or the subthalamic nucleus (STN) has shown efficacy for Meige syndrome (MS), there is limited comparative evidence available. METHODS: This retrospective cohort study consecutively enrolled patients with primary MS who underwent bilateral GPi-DBS or STN-DBS at our center between March 2015 and February 2025. Propensity score matching (PSM, 1.5:1) was employed to balance baseline covariates. The primary outcomes were improvements in the Burke-Fahn-Marsden Dystonia Rating Scale movement subscore (BFMDRS-M) at 3-month (short-term) and at the final follow-up (long-term). Additionally, stimulation parameters, programming adjustments, and adverse events (AEs) were analyzed. RESULTS: The study cohort comprised 254 eligible patients (GPi-DBS: 176; STN-DBS: 78), with 14 patients (4.8%) lost to follow-up. The overall cohort consisted of 178 women (70.1%) with a mean surgical age of 57.7 ± 8.6 years. After PSM, 157 patients were matched (89 GPi-DBS, 68 STN-DBS). At 3-month follow up, the mean improvement rate of BFMDRS-M total score was 51.0% [95% confidence interval (CI): 46.7-55.3%] for GPi-DBS and 54.6% (95% CI: 49.3-59.8%) for STN-DBS, with no significant intergroup difference (P = 0.235). After a mean follow-up of 42.4 ± 23.6 months, the mean improvement was 61.0% (95% CI: 56.4-65.5%) for GPi-DBS and 65.2% (95% CI: 59.2-71.1%) for STN-DBS, again indicating no significant difference ( P = 0.192). STN-DBS required lower stimulation parameters but significantly more programming adjustments than GPi-DBS (mean sessions: 5.49 vs 4.33; P < 0.001). AE incidence was similar between groups (GPi-DBS vs STN-DBS: 5.4% vs 3.6%; P = 0.731). CONCLUSIONS: Both GPi-DBS and STN-DBS provided significant and sustained motor symptom improvement in refractory MS, with no statistically significant difference between groups.