Weight changes in patients with Parkinson's disease treated with Deep Brain Stimulation.

1 Abstract Body weight changes have been described in the course of Parkinson's disease (PD) as well as following bilateral deep brain stimulation of the subthalamic nucleus (STN DBS) performed in advanced PD. According to the literature weight changes occur in 50-100% of patients who undergo STN DBS. In the last 15 years extensive efforts have been put in understanding the underlying mechanisms behind the weight changes following STN DBS in advanced PD patients however many sources still report conflicting evidence. Improved motor status, reduction in dyskinesias, decrease in energy expenditure, dopaminergic medication reduction, modification of food intake, hormonal factors, regional effects of stimulation were all speculated to cause this weight gain. We hypothesized that patients who underwent STN DBS procedure in our center would gain weight as reported in the literature (study 1, study 2). The etiology of post STN DBS weight gain has not been fully elucidated up to date, in our second study we further hypothesized that the weight changes are due to dysregulation of food related hormones and parameters (study 2). In the third study we hypothesized that weight gain is associated with position of active electrode contact (study 3). Aims of the study: The primary aims of our studies were to assess body..