Sw2-year outcomes of subthalamic deep brain stimulation for idiopathic Parkinson's disease

Abstract

Background: Deep brain stimulation of the subthalamic nucleus (STN-DBS) is the recent surgical treatment of choice for patients with idiopathic Parkinson's disease (PD) complicated by motor fluctuation and disabling dyskinesia. Objective: To study 2 years clinical outcomes, changes of medication and complications following STN-DBS in patients with advanced PD. Material and Method: Twenty-seven patients with 2-year follow-up and complete data were enrolled for retrospective evaluation of Unified Parkinson's Disease Rating Scale (UPDRS) and levodopa equivalent dose (LED). Postoperative UPDRS at 6-month, 1-year and 2-years were compared with the preoperative corresponding UPDRS. Postoperative LED at 2 years was compared with the preoperative baseline. Statistical analysis was performed with paired t-test. Additionally, 62 patients with STN-DBS were enrolled for evaluation of treatment complications. Results: Of 27 patients with complete 2-years follow-up, preoperative dopamine challenge test showed 50.6% improvement of motor score (UPDRS axis III). Mentation, behavior and mood (UPDRS axis I) were not significantly improved in each subscore, but significantly improved in the total score. Marked improvement of activities of daily living (UPDRS axis II) and complications of therapy (UPDRS IV) was found. Two-year postoperative motor score (UPDRS axis III) during "off medication-on stimulator" showed progressive and dramatic improvement by mean of 59.83%. The present study also revealed significant improvement of motor score (UPDRS axis III) during "on medication-on stimulator" in some items. A significant 33.4% reduction of LED was noted. Of 62 patients with bilateral STN-DBS, there was 1 asymptomatic intracerebral hemorrhage (0.8% per side), 2 speech difficulty (3.2%), 1 transient confusion (1.6%), 2 transient hypomania (3.2%), 1 stimulation induced hemiballism (1.6%), 1 wound infection (1.6%) and 1 lead malposition (0.8% per side). Conclusion STN-DBS is a safe and effective treatment for PD complicated by motor fluctuation or dyskinesia. The operative outcomes show long-term improvement of activities of daily living, motor function and reduction of medication and drugrelated complications.