Abstract
BACKGROUND: The up-to-date literature systematically reviewing the predictive value of preoperative levodopa responsiveness after deep brain stimulation (DBS) surgery in motor outcomes in Parkinson's disease (PD) is lacking. OBJECTIVE: To address this issue in patients with PD undergoing bilateral subthalamic nucleus (STN) or globus pallidus interna (GPi) DBS. METHODS: We used the existing PRISMA consensus statement. A comprehensive review of literature from 1993 to May 2021 retrieved from PubMed was conducted. RESULTS: The STN-DBS responsiveness was significantly correlated with the preoperative levodopa responsiveness for the total score of UPDRS-III at both 6- and 12-month follow-ups (P < 0.001). Such correlations were significant after controlling for age at time of surgery and disease duration. The significance of correlation disappeared for longer follow-up times. For the sub-scores of UPDRS-III, a significant correlation between the preoperative levodopa responsiveness and STN DBS responsiveness was observed for rigidity, bradykinesia, and axial symptoms, but not for tremor (P = 0.002, 0.010, 0.007, and 0.542, respectively). The preoperative levodopa responsiveness was significantly correlated with GPi DBS responsiveness for the UPDRS-III total score at a median follow-up of 12 months (P = 0.030). CONCLUSION: The current study confirmed the value of preoperative levodopa responsiveness for prediction of the short-term motor outcome after DBS (for both STN and GPi). The predictive value of levodopa responsiveness in short-term outcomes for respective cardinal motor disabilities and the loss of its predictive value after STN DBS for long-term motor outcomes were highlighted by this study.