Effects of Subthalamic Nucleus Deep Brain Stimulation on Gastrointestinal Symptoms and Motility in Parkinson's Disease.

Patients with Parkinson's disease (PD) frequently experience upper gastrointestinal disorders. During the disease, weight loss is often noticed. Recently, many studies have demonstrated that STN-DBS improved extrapyramidal symptoms. Interestingly, PD patients gain weight after STN-DBS, at least in part due to a decrease in resting energy expenditure.

Purpose: To evaluate benefits of STN-DBS on upper gastrointestinal symptoms and motility.

Patients et method: PD patients waiting for STN-DBS, will be assessed in a preoperative time (2 times at, at least, 3 month intervals, to evaluate the natural history of the disease on upper gastrointestinal symptoms and motility) and in a postoperative time, after 6 months of chronic STN-DBS. Each assessment will include : 1/ questionnaires about frequency and severity of upper gastrointestinal symptoms; 2/ a nutritional assessment (body mass index, dietary assessment); 3/ the gastric emptying measurement with the 13C-octanoic acid breath test; 4/ the colorectal transit time measurement with radio-opaque markers 5/ an indirect calorimetry to estimate resting energy expenditure; 6/ and plasmatic leptin and ghrelin concentrations, hormones involved in the homeostatic regulation of appetite.

Perspectives: This physiopathological study should allow us to understand the mechanisms of the effects of STN-DBS on upper gastrointestinal symptoms and weight regulation in PD patients.