Influence of Glucose on Metabolism and Clinical Symptoms of Patients With Parkinson's Disease

NCT ID: NCT05998772

Last Updated: 2025-09-22

Basic Information

• Recruitment Status: RECRUITING
• Total Enrollment: 50 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2023-09-01
• Study Completion Date: 2025-12-31

Brief Summary

Many patients with Parkinson's Disease (PD) report an increased consumption of fast-acting sugars. This tendency to consume sweet, high-sugar foods occurs in some patients even before the onset of cardinal motor symptoms. Some recent studies have demonstrated that PD patients have an increased consumption of fast-acting carbohydrates compared to healthy controls. However, the reason for this change in eating behavior has not yet been adequately explained. It is discussed that the increased sugar intake leads to an increased dopamine release in the brain via an increase in insulin and thus to an improvement in clinical symptoms. This study investigates the influence of fast-acting carbohydrates on insulin and glucose blood levels as well as motor and non-motor symptoms in patients with PD using an oral glucose tolerance test and a placebo oral glucose tolerance test in a crossover design.

Conditions

Parkinson Disease; Nutritional and Metabolic Diseases; Sugar Intake

Study Design

• Observational Model Type: CASE_CROSSOVER
• Study Time Perspective: PROSPECTIVE

Study Groups

PD patients with craving for sweets

Oral Glucose Tolerance Test

Intervention Type: DIAGNOSTIC_TEST

Application of 82,5 g of glucose monohydrate solved in 300ml water

Placebo Oral Glucose Tolerance Test

Intervention Type: OTHER

Application of 125mg sucralose solved in 300ml water

PD patients without craving for sweets

Oral Glucose Tolerance Test

Intervention Type: DIAGNOSTIC_TEST

Application of 82,5 g of glucose monohydrate solved in 300ml water

Placebo Oral Glucose Tolerance Test

Intervention Type: OTHER

Application of 125mg sucralose solved in 300ml water

Interventions

Oral Glucose Tolerance Test

Application of 82,5 g of glucose monohydrate solved in 300ml water

Intervention Type: DIAGNOSTIC_TEST

Placebo Oral Glucose Tolerance Test

Application of 125mg sucralose solved in 300ml water

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Diagnosis of Parkinson's Disease, stage Hoehn & Yahr 1.5-3
• Ability to pause antiparkinsonian medication in the morning without relevant impairment
• Capacity to give consent (determined in doubt by two independent neurologists, MOCA ≥18) and written informed consent.
• Patients are between 50 and 80 years of age, with exceptions for a maximum of 5 additional patients enrolled per group
• For stratification into patients with and without sweet craving, a 3-day dietary protocol should be completed once by the patients
• Group I: increased hunger for sweets.
• Group II: no increased hunger for sweets.

For the stratification into patients with and without increased hunger for sweets, participants are asked to answer the following questions:

1. Do you have sudden attacks of cravings for sweets?

2. Would you say that your consumption of sweet food has increased in recent years?

3. Would you describe your consumption of sugary food as increased or excessive?

If one of the questions is answered with yes, participants will be assigned to group I, if all questions are answered with no, participants will be assigned to group II.

Exclusion Criteria

• Other significant neurological diseases primarily affecting the central nervous system (e.g., multiple sclerosis)
• Diagnosis of diabetes mellitus or prediabetes
• Use of medications that affect glucose metabolism, such as antidiabetics, glucocorticoids, ciclosporin, tacrolimus, sirolimus, beta-blockers, thiazide diuretics, beta-2 adrenoreceptor agonists, theophylline, Clozapine, olanzapine, paliperidone, quetiapine, risperidone, tricyclic antidepressants, mirtazapine, mianserin, carbamazepine, gabapentin, pregabalin, valproic acid, lithium, antiretroviral drugs, statins
• cardiac or brain pacemakers

• Minimum Eligible Age: 50 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of Kiel

OTHER

Sponsor Role: collaborator

University Hospital Schleswig-Holstein

OTHER

Sponsor Role: lead

Responsible Party

Eva Schaeffer

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Department for Neurology, University of Kiel

Kiel, , Germany

Site Status: RECRUITING

Countries

Germany

Central Contacts

Eva Schäffer, MD

Role: CONTACT

eva.schaeffer@uksh.de

004943150023983

Julienne Haas, MD

Role: CONTACT

julienne.haas@uksh.de

Facility Contacts

Eva Schäffer, Dr.

Role: primary

eva.schaeffer@uksh.de

004943150023983

Other Identifiers

D 537/23

Identifier Type: -

Identifier Source: org_study_id