Weight Changes in Subthalamic Nucleus vs Globus Pallidus Internus Deep Brain Stimulation: Results From the COMPARE Parkinson Disease Deep Brain Stimulation Cohort

BACKGROUND: Parkinson's patients, on average, gain weight after deep brain stimulation (DBS). OBJECTIVE: To determine potential differences in weight gain when comparing the subthalamic nucleus and the globus pallidus internus target. METHODS: A retrospective analysis was performed on the prospective, randomized cohort of National Institutes of Health COMPARE trial DBS patients who received unilateral subthalamic nucleus or globus pallidus internus DBS. Baseline weights were recorded before DBS surgery and at 6, 12, and 18 months postoperatively. Relationships between weight change and changes in Beck Depression Inventory score, Unified Parkinson's Disease Rating Scale (UPDRS) motor score (part III) (also the dyskinesia duration and disability subscores from UPDRS IV), and Hoehn-Yahr stage were determined via Spearman's rank-order correlation coefficients. Regression analyses were performed to investigate the effects of potential factors on weight change over time. RESULTS: Patients in the COMPARE DBS cohort gained a significant amount of weight, a mean of 4.86 lb (standard deviation = 8.73) (P = .001), but there was no significant difference between subthalamic nucleus and globus pallidus internus targets (weight gain of 4.29 +/- 6.79 and 5.38 +/- 10.32 lb, respectively; P = .68). Weight gain did not correlate with Beck Depression Inventory score change, UPDRS motor score, dyskinesia duration, dyskinesia disability change, or the Hoehn-Yahr stage (P = .62, .21, and .31, respectively). No specific variable was associated with weight gain, and there were no differences in binge eating post-surgery in either target. CONCLUSION: There were significant changes in weight over time after DBS therapy. However, neither Beck Depression Inventory score change nor UPDRS score change or dyskinesia was correlated with weight gain. No significant factor was associated with the weight change.