This clinical trial evaluates whether adherence to a Mediterranean diet for three months following bilateral subthalamic nucleus (STN) deep brain stimulation surgery can help control body weight gain and improve body composition in Parkinson's disease patients. Conducted by researchers at Ankara University (Turkey), the trial addresses a significant clinical gap: the metabolic complications that frequently follow STN deep brain stimulation (DBS) in PD patients[1].
| Parameter | Value |
|---|---|
| NCT Number | NCT07187739 |
| Official Title | Investigation of the Effect of the Mediterranean Diet on Nutritional Status in Parkinson's Patients Undergoing Bilateral Subthalamic Nucleus Deep Brain Stimulation |
| Status | Recruiting (verified 2025-10) |
| Phase | Not Applicable |
| Study Type | Interventional |
| Enrollment | 24 participants (estimated) |
| Study Design | Randomized, Parallel Assignment, No Masking |
| Start Date | September 25, 2025 (actual) |
| Primary Completion | March 2026 (estimated) |
| Completion Date | March 2026 (estimated) |
| Lead Sponsor | Ankara University |
| Principal Investigator | Nursena ERSOY SÖKE, MsC |
| Locations | Ankara Etlik City Hospital, Ankara, Turkey |
Bilateral subthalamic nucleus deep brain stimulation is a highly effective treatment for advanced Parkinson's disease, particularly for patients experiencing motor fluctuations and dyskinesia despite optimal pharmacological therapy. However, a well-documented side effect is significant body weight gain following surgery[2]. This weight gain occurs through several mechanisms:
The ESPEN (European Society for Clinical Nutrition and Metabolism) guideline on clinical nutrition in neurology specifically recommends nutritional therapy for DBS patients to control post-operative weight gain and prevent metabolic disorders[3].
The Mediterranean diet is characterized by:
This dietary pattern has demonstrated beneficial effects on:
The Mediterranean diet intervention begins at the time of DBS device activation (typically 2-4 weeks post-surgery) and continues for three months:
Dietary Recommendations Include:
Follow-up Structure:
The control group continues their routine/usual diet without specific dietary guidance. This allows researchers to isolate the effect of the Mediterranean diet intervention from natural post-DBS dietary changes.
| Timepoint | Assessments |
|---|---|
| Baseline (pre-operative) | Anthropometrics, body composition, appetite, QoL, motor symptoms, dietary recall |
| 1-month post-operative | All measures + 3-day food record |
| 2-month post-operative | All measures + 3-day food record |
| 3-month post-operative | All measures + 3-day food record + Mediterranean Diet Adherence Scale |
| Measure | Description |
|---|---|
| Body Weight | Measured with body analyzer sensitive to 0.1 kg |
| Height | Measured in cm with portable stadiometer (Frankfort plane position) |
| Body Mass Index | BMI calculated as weight (kg) / height squared (m²) |
| Measure | Description |
|---|---|
| Triceps Skinfold Thickness | Caliper measurement in mm for adipose tissue assessment |
| Upper Mid-arm Circumference | Non-stretchable tape measure in cm |
| Upper Mid-arm Muscle Circumference | Calculated from arm circumference and triceps skinfold |
| Upper Mid-arm Muscle Area | Calculated in cm² for lean body mass assessment |
| Motor Symptoms (Nutrition) | MDS-UPDRS Part 2 sections 2.2 (chewing/swallowing) and 2.4 (eating) — 5-point Likert scale |
| Dietary Intake | 24-hour dietary recall + 3-day food consumption records analyzed via Nutrition Information System (BEBIS) |
| Quality of Life | PDQ-8 (Parkinson's Disease Questionnaire-8), 5-point Likert scale, converted to 0-100 score |
| Appetite Status | 100 mm Visual Analogue Scale (anchored: "very poor" to "very good") |
| Mediterranean Diet Adherence | 14-item Mediterranean Diet Adherence Scale (score ≥7 indicates acceptable compliance) |
Participants are randomized into intervention and control groups stratified by age, gender, disease severity (Hoehn & Yahr stage), and body mass index. No healthy volunteers are included.
Post-STN DBS weight gain is multifactorial. The Mediterranean diet intervention targets several pathways:
The Mediterranean diet may influence multiple pathways relevant to PD:
STN DBS is one of the most effective surgical treatments for advanced Parkinson's disease, with studies demonstrating significant improvements in motor symptoms, quality of life, and medication requirements. However, the post-operative weight gain creates a paradox: improved mobility comes with increased metabolic risk.
The trial directly addresses this gap by applying evidence-based nutritional intervention. If successful, the Mediterranean diet approach could become standard post-DBS care.
The study uses comprehensive nutritional assessment tools:
NCT07187739 — Effect of Mediterranean Diet on Nutrition in Parkinson's Disease Patients With Bilateral Subthalamic Deep Brain Stimulation. ↩︎
Guimaraes J, Matos E, Rosas MJ, et al. Modulation of nutritional state in Parkinsonian patients with bilateral subthalamic nucleus stimulation. Journal of Neurology. 2009. ↩︎
Burgos R, Breton I, Cereda E, et al. ESPEN guideline clinical nutrition in neurology. Clinical Nutrition. 2018. ↩︎