Investigation of the Effect of the Mediterranean Diet on Nutritional Status in Parkinson's Patients Undergoing Bilateral Subthalamic Nucleus Deep Brain Stimulation

Parkinson's disease is a neurodegenerative disease characterized by the loss of dopaminergic neurons in the substantia nigra region. Although the prevalence of Parkinson's disease varies according to gender and geographical region, the prevalence increases with age. Parkinson's Disease is characterized by three motor symptoms: tremor, bradykinesia and rigidity. Aside from motor symptoms, non-motor symptoms are also present. The majority of non-motor symptoms consist of gastrointestinal symptoms such as dysphagia, gastroparesis and constipation. The most effective pharmacological drug for treating motor symptoms in Parkinson's patients is levodopa (3,4-dihydroxyphenylalanine). Deep brain stimulation (DBS: Deep Brain Stimulation) may be a treatment option in patients who have motor fluctuation, dyskinesia or tremor symptoms despite optimal drug therapy. Deep brain stimulation is a minimally invasive, targeted neurosurgical intervention that involves placing electrodes and a pacemaker that electrically stimulates these electrodes in structures deep in the brain. Over the past 25 years, deep brain stimulation has been used extensively to target various brain regions. The most preferred method is Subthalamic Nucleus DBS. The suitability of this treatment for patients is determined by a multidisciplinary team based on the presence of various indications. In these patients, body weight gain may be observed after surgery due to increased food intake, decreased motor symptoms, and decreased energy expenditure due to physical activity. Body weight is associated with increasing levodopa dosage, dyskinesia, and risk of metabolic syndrome. To prevent this important side effect of DBS, the European Society of Enteral and Parenteral Nutrition emphasizes nutritional therapy in patients to control post-operative body weight gain and prevent the onset of metabolic disorders. The primary aim of this study was to examine the effect of Mediterranean dietary recommendations on body weight and body composition during three months post-operatively in adult patients undergoing STN DBS. Inclusion criteria for the study are as follows: being between 45 and 64 years of age, volunteering to participate, having undergone bilateral subthalamic nucleus deep brain stimulation (STN DBS) surgery, continuing antiparkinsonian treatment, and having a Mini-Mental State Examination (MMSE) score of 24 or higher. Exclusion criteria include having any psychiatric disorder, having a Mini-Mental State Examination (MMSE) score below 24, and having a disease other than Parkinson's disease that requires a special diet. Participants who meet the inclusion criteria will be randomized into two groups: intervention and control groups. Participants in the control group will be instructed to continue their current eating habits. Participants' appetite will be assessed by the investigators using the "Visual Appetite Scale", disease stage using the "Hoehn and Yahr Questionnaire", quality of life using the "Parkinson Disease Quality of Life Questionnaire-8", motor symptoms related to feeding (chewing and swallowing, eating) using the "Movement Disorder Society Unified Parkinson's Disease Rating Scale - Part 2", adherence to the Mediterranean diet using the "Mediterranean Diet Adherence Scale", diet assessment using the "Food Consumption Record" and physical activity status using the "International Physical Activity Questionnaire-Short Form" by the investigators. In order to determine the daily energy and nutrient consumption status of participants, a 24-hour dietary recall will be taken in the pre-operative interview, and a total of three days of food consumption records will be taken in the post-operative 1st, 2nd and 3rd interviews, one day of which will be 24-hour recall and two days of which will be food recording method. Visual Appetite Scale, Hoehn and Yahr Questionnaire, Parkinson's Disease Quality of Life Questionnaire-8, Movement Disorder Association Unified Parkinson's Disease Rating Scale - Part 2, and Mediterranean Diet Adherence Scale will be applied by the investigators to all participants at preoperative, post-operative 1st, 2nd and 3rd month. In addition, participants' anthropometric measurements (body weight, waist circumference, neck circumference, upper mid-arm circumference, handgrip strength) and body composition will be evaluated by the investigators. All data obtained during the research process will be evaluated using appropriate statistical analysis.