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Psychological Effects of Levodopa in Parkinson's Disease

Unravelling the Impact of Levodopa on Dysfunctional Brain Networks in Parkinson's Disease With Neuropsychiatric Fluctuations

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05119075
Enrollment
23
Registered
2021-11-12
Start date
2021-11-10
Completion date
2024-03-31
Last updated
2025-04-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Parkinson Disease

Keywords

Neuropsychiatric fluctuations, Creativity, Shame, Embarrassment, Non-motor symptoms, Hallucinations, Bradyphrenia

Brief summary

The investigators aim is to study neuropsychiatric symptoms and underlying abnormalities in resting-state fMRI in patients with Parkinson's disease (PD) suffering from neuropsychiatric fluctuations, to enhance the understanding of the pathophysiological mechanisms underlying neuropsychiatric symptoms.

Detailed description

Parkinson's disease (PD) is primarily classified and known as a movement disorder characterized by tremor, bradykinesia and rigidity. However, clinical examination and research have shown that PD extensively affects other systems as well, giving rise to non-motor symptoms (NMS) such as anxiety, sleep disorders, apathy, depression, cognitive impairment, and hallucinations. These non-motor fluctuations (NMF) represent a main source of disability in PD and among those, neuropsychiatric fluctuations are the most frequent. During the dopaminergic OFF-drug state anxiety, apathy, and depression are common, whereas during the dopaminergic ON-drug state euphoria, well-being, impulse control disorders (ICD) and other behavioral addictions, mania, and psychosis might occur. Despite the severe consequences associated with dopaminergic modulation, the understanding of the pathophysiological mechanisms of neuropsychiatric symptoms is still limited and better detection and more effective treatments are needed. Fluctuating PD is a very powerful model allowing to study opposite psychiatric states intra-individually in both levodopa dopaminergic ON- and OFF-drug state, allowing to abstract many interpersonal variables. Neurotechnology and advanced neuroimaging techniques can improve the understanding of the neural basis and brain mechanisms of specific neuropsychiatric symptoms in PD. In particular, dynamic functional connectivity (FC) analysis characterizes functional abnormalities from resting state (rs)-fMRI not only in terms of brain activations, but also of whole-brain functional networks and the transitions between maps of activations. The temporal evolution of these networks, assessed with dynamic FC approaches, has recently shown to be relevant in several clinical contexts. Therefore, the investigators long-term goal is to identify specific resting-state signatures/biomarkers for the individual neuropsychiatric PD symptoms related to disease in dopaminergic OFF-drug state (depression, anxiety, apathy, fatigue, shame, bradyphrenia) and to dopaminergic treatment in dopaminergic ON-drug state (mania, impulse control disorders, hallucinations, psychosis, creative thinking), which might be used in the future as a proxy for the measurement of neuropsychiatric symptoms/fluctuations and thus to assess the effectiveness of specific therapies.

Interventions

OTHERDopaminergic OFF-drug state

Dopaminergic OFF-drug state: Overnight withdrawal of dopaminergic antiparkinsonian drugs during visit 3 or 4. The sequence of drug conditions (dopaminergic OFF-drug/ON-drug state or ON-drug/OFF-drug state) will be randomized.

OTHERDopaminergic ON-drug state

Dopaminergic ON-drug state: Patient will be evaluated in his/her regular treatment in dopaminergic ON-drug state at visit 3 or 4. The sequence of drug conditions (dopaminergic OFF-drug/ON-drug state or ON-drug/OFF-drug state) will be randomized.

Sponsors

University Hospital, Geneva
CollaboratorOTHER
Ecole Polytechnique Fédérale de Lausanne
CollaboratorOTHER
Insel Gruppe AG, University Hospital Bern
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Adults above 18 years old * Male or female * Diagnosed with Parkinson's disease * Able to understand instructions, neuropsychological tests and provide written informed consent * Able to understand the locally used language of the experimental site and speak fluently * Presence of neuropsychiatric fluctuations, defined as the sum ≥ 3 of items included in the Ardouin Scale of Behaviour in Parkinson's Disease (ASBPD) part 2

Exclusion criteria

* Structural brain disease other than Parkinson's disease * Substance abuse and/or dependence (other than DRT) * Ongoing depression with suicidal ideation * Severe tremors/dyskinesia/ interfering with MRI performance * Participating in a pharmacological study * Inability to provide informed consent (legal guardianship) * MRI contraindications * Pregnancy

Design outcomes

Primary

MeasureTime frameDescription
Correlation of functional connectivity abnormalities with creativity≤ 6 weeksScore on the Creative Thinking Scale
Correlation of functional connectivity abnormalities with neuropsychiatric fluctuations≤ 6 weeksScore on the Neuropsychiatric Fluctuations Scale (NFS)
Correlation of functional connectivity abnormalities with shame≤ 6 weeksScore on the Shame Visual Analogic Scale
Correlation of functional connectivity abnormalities with hallucinations≤ 6 weeksScore on robot-induced presence hallucination (PH) ratings
Correlation of functional connectivity abnormalities with bradyphrenia≤ 6 weeksScore on the Bradyphrenia Scale

Secondary

MeasureTime frameDescription
The role of dopamine on creativity≤ 6 weeksMeasurement of the influence of dopamine on the Creative Thinking Scale. Assessments will be performed under the two conditions (dopaminergic ON and OFF drug state) and compared. The higher the score, the more creative the patients are.
The role of dopamine on shame≤ 6 weeksMeasurement of the influence of dopamine on the Shame Visual Analogic Scale. Assessments will be performed under the two conditions (dopaminergic ON and OFF drug state) and compared. The higher the score, the more shame patients feel.
The role of dopamine on bradyphrenia≤ 6 weeksMeasurement of the influence of dopamine on the bradyphrenia scale. Assessments will be performed under the two conditions (dopaminergic ON and OFF drug state) and compared. The higher the score, the more bradyphrenic the patients are.
The role of dopamine on hallucinations≤ 6 weeksMeasurement of the influence of dopamine on hallucinations using the robot-induced presence hallucination (PH) ratings. Assessments will be performed under the two conditions (dopaminergic ON and OFF drug state) and compared. The higher the score, the more hallucinations are experienced by patients.

Countries

Switzerland

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026