Weight gain following subthalamic nucleus deep brain stimulation: a PET study

Area of Science:

• Neuroscience
• Metabolic Disorders
• Medical Imaging

Background:

• Weight gain is a known adverse effect of deep brain stimulation (DBS).
• Existing hypotheses do not fully explain the mechanisms behind DBS-induced weight gain.
• Parkinson's disease (PD) patients undergoing DBS often experience metabolic changes.

Purpose of the Study:

• To investigate the correlation between brain metabolism changes and weight gain after subthalamic nucleus DBS in Parkinson's disease patients.
• To identify specific brain regions where metabolic alterations are associated with weight gain post-DBS.
• To differentiate metabolic changes in associative/limbic versus sensorimotor areas in relation to weight gain.

Main Methods:

• Positron emission tomography (PET) imaging using 2-deoxy-2[18F]fluoro-D-glucose was employed.
• Brain activity was measured 3 months before and 4 months after bilateral subthalamic nucleus DBS in 23 PD patients.
• Body mass index (BMI) changes were analyzed alongside motor complications (UPDRS-IV) and dopaminergic medication to control for confounding factors.

Main Results:

• A significant increase in mean BMI (0.8 ± 1.5 kg/m(2)) was observed post-DBS (P = 0.03).
• Weight gain correlated with metabolic changes in limbic and associative brain areas, including the orbitofrontal cortex, temporal lobe, anterior cingulate cortex, and retrosplenial cortex.
• No correlation was found between weight gain and metabolic changes in sensorimotor brain regions.

Conclusions:

• Metabolic alterations in associative and limbic brain networks contribute to weight gain following subthalamic nucleus DBS in Parkinson's disease.
• These findings highlight the role of non-motor brain circuits in the metabolic side effects of DBS.
• Understanding these mechanisms may lead to strategies for managing weight gain in DBS patients.