Role of Pre-operative Mild Cognitive Impairment in Patients Undergoing Deep Brain Stimulation for Parkinson’s Disease: Systematic Review
Pooja Dhupati1, Sunny Vansdadia1, Priya Ramaiah1, Cherry Barragan1, Eujung Park1, Robert Bina2, Sara Dhanani3
1University of Arizona College of Medicine - Phoenix, 2Neurosurgery, University of Arizona College of Medicine - Phoenix, 3Movement Disorders Neurology, Banner Sun Health Research Institute
Objective:
This systematic review aims to consolidate existing evidence on the influence of preoperative MCI on postoperative DBS outcomes in patients with PD. By analyzing the methodological constraints of existing studies, this analysis aims to inform future research on the safety and efficacy of DBS surgery for patients with PD-MCI.
Background:
Despite the high estimated prevalence of mild cognitive impairment (MCI) among patients with Parkinson’s disease (PD), no published guidelines exist for determining post-operative risk after deep brain stimulation (DBS) among PD-MCI patients. While the benefits of DBS for the treatment of motor symptoms in advanced PD are well-established, few studies examine how preoperative MCI affects DBS outcomes.
Design/Methods:
A PRISMA-compliant systematic review across four databases was conducted for studies establishing preoperative MCI using at least one standardized measure and reporting post operative outcomes in PD-MCI patients. Data regarding mean disease duration, DBS target, follow up time points, MCI measures and clinical outcomes including QOL measures were extracted.
Results:
Of 330 records, 8 articles met inclusion criteria, spanning 580 total patients undergoing PD-DBS with pre-operative MCI. Of the 4 studies reporting a difference in PD-DBS outcomes in MCI patients, the differing outcomes in the MCI group involved cognitive domains and the rate of progression to dementia. None of the studies included a matched control of non-operated patients, although 7 included a PD-NC cohort. Three (37.5%) studies included at least one QOL measure.
Conclusions:
The precise role of preoperative MCI on post-DBS outcomes remains speculative given the paucity of existing literature. Definitions of MCI are variable between studies, further complicating methodological comparisons. Furthermore, the clinical relevance of outcomes beyond standardized scales, such as QOL outcomes and caregiver burden, are less definitive. Ultimately, understanding the role of preoperative baseline characteristics, such as MCI, in surgical outcomes among PD DBS candidates could strengthen patient selection and counseling.