Objective: To describe the association between medication adjustments with mood and pain following bilateral deep brain stimulation (DBS) in Parkinson’s disease (PD).

Background: Depression, anxiety, apathy, impulsivity, and pain are common nonmotor symptoms of PD. Some studies demonstrate that nonmotor symptoms improve with bilateral DBS, depending on the site of stimulation.  Studies comparing STN and GPi DBS report that patients undergoing STN DBS may experience worse mood outcomes after surgery; this may be related to post-surgical medication adjustments. Both STN and GPi DBS can alleviate PD related pain by targeting fluctuation-related discomfort due to dystonia and dyskinesia. In this pilot study, we measured medication adjustments, mood, and pain in PD patients undergoing either bilateral STN or GPi DBS.

Method: PD patients undergoing bilateral STN (10) or GPi DBS (17) were prospectively followed over three years (2020-2023). Data related to PD medications, levodopa equivalent daily dose (LEDD), and mood assessments (Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Apathy Scale (AS), Questionnaire for Impulsive-Compulsive Disorders in Parkinson’s Disease-Rating Scale (QUIP-RS)) were collected at baseline, 1 week, 1 month, 3 months, and 6 months, as well as King’s Parkinson’s Pain Scale (KPPS) at baseline and 6 months after surgery. We used Wilcoxon signed-rank tests for paired pre-post comparisons.

Results: LEDD at 6 months were significantly lower than baseline (p=0.04), particularly within the patients undergoing GPi DBS (p=0.007). Patients undergoing GPi DBS had significantly lower BAI scores at 3 months (p=0.002) and 6 months (p=0.005) compared to baseline. BAI scores remained unchanged for patients undergoing STN DBS; BDI, QUIP-RS, and AS scores remained unchanged for all patients and target groups between baseline and 6 months. Total KPPS was lower with a trend towards significance for all patients (p=0.06) at 6 months; KPPS domain 3 (fluctuation-related pain) scores were significantly lower at 6 months for patients undergoing GPi DBS (p=0.02), compared to baseline, though not for patients undergoing STN DBS, compared to baseline.

Conclusion: Bilateral GPi DBS is associated with greater relief of fluctuation-related pain in PD, which may result in lower anxiety. Patients with fewer nonmotor symptoms may require lower LEDD after surgery. These findings can impact ideal target selection for DBS in PD patients.

« Back to 2024 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/effect-of-target-selection-on-mood-pain-and-medications-after-dbs-in-pd/