Weight and survival after deep brain stimulation for Parkinson’s disease

Congratulations Drs. Okun, Foote, Ramirez-Zamora, and Gunduz on the publication of “Weight and survival after deep brain stimulation for Parkinson’s disease,” which appears in the August 17th issue of Parkinsonism and Related Disorders.

Abstract

Background

Weight loss in Parkinson’s disease (PD) is common and associated with increased mortality. The clinical significance of weight changes following deep brain stimulation (DBS) of the subthalamic nucleus (STN) and globus pallidus internus (GPi) is unclear.

Objectives

To address (1) whether PD patients exhibit progressive weight loss, (2) whether staged DBS surgery is associated with weight changes, and (3) whether survival after DBS correlates with post-DBS weight.

Methods

This is a single-center, longitudinal, retrospective cohort study of 1625 PD patients. We examined trends in weight over time and the relationship between weight and years survival after DBS using regression and mixed model analyses.

Results

There was a decline in body weight predating motor symptom onset (n = 756, 0.70 ± 0.03% decrease per year, p < 0.001). Weight decline accelerated in the decade preceding death (n = 456, 2.18 ± 0.31% decrease per year, p < 0.001). DBS patients showed a weight increase of 2.0 ± 0.33% at 1 year following the first DBS lead implant (n = 455) and 2.68 ± 1.1% at 3 years if a contralateral DBS lead was placed (n = 249). The bilateral STN DBS group gained the most weight after surgery during 6 years of follow up (vs bilateral GPi, 3.03 ± 0.45% vs 1.89 ± 0.31%, p < 0.01). An analysis of the DBS cohort with date of death available (n = 72) revealed that post-DBS weight (0–12 months after the first or 0–36 months after the second surgery) was positively associated with survival (R2 = 0.14, p< 0.001).

Discussion

Though PD is associated with significant weight loss, DBS patients gained weight following surgery. Higher post-operative weight was associated with increased survival. These results should be replicated in other cohorts.