An observational study in Parkinson Disease, sponsored by Danish Research Centre for Magnetic Resonance. Active, not recruiting at 1 site in Denmark. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-05-22.
Sponsored by Danish Research Centre for Magnetic Resonance · Observational
Levodopa-induced dyskinesia (LID) in Parkinson's disease (PD) are involuntary movements caused by long-term treatment with dopaminergic replacement therapy (levodopa). During the cause of PD, most patients develop LID. In this study, the investigators plan to investigate how the cortico-basal-ganglia networks are affected in LID. The investigators will examine PD patients with and without LID as well as healthy age-matched controls using fMRI and PET. During the fMRI experiment, participants will perform a novel go-no task engaging both motor, emotional and reward brain networks. Patients will be scanned before and after intake of levodopa to study the dynamic effects of dopaminergic therapy. Furthermore, a dopamine transporter PET will be acquired to study the dopaminergic degeneration of the patients with PD.
BACKGROUND Parkinson's disease (PD) is a neurodegenerative disease affecting the cortico-basal-ganglia network including dopaminergic degeneration. PD is treated with dopaminergic replacement therapy such as levodopa which is a natural precursor of dopamine. Unfortunately, most patients develop involuntary movements after many years of treatment which are called levodopa-induced dyskinesia (LID). Little is known about how brain networks are disturbed in LID. To investigate this, the investigators will conduct a multimodal characterization of PD patients with LID. Patients with and without LID will be studied using dynamic task-based fMRI to trace the levodopa-induced changes in functional brain activity and connectivity in the transition from the off-to-on medication state. For the task-based fMRI, the investigators will employ a novel experimental task that concurrently engages motor, emotional, and reward networks. Furthermore, the investigators will also map and quantify the dopaminergic presynaptic deficit using dopamine transporter (DAT) PET ([18F]PE2I-PET) to correlate the findings with MRI.
This study is part of a larger study of brain phenotyping PD (ADAPT-PD) with MRI.
AIM This sub-study aims to achieve a multimodal characterization of LID in PD using both fMRI and DAT PET. Furthermore, both motor, reward and emotional cortico-basal-ganglia networks will be investigated. The result of this study will lay the foundation of a future non-invasive brain stimulation study using transcranial magnetic stimulation (TMS) in PD.
HYPOTHESES
The analysis regarding reward and emotional processing in patients with LID and the comparisons between fMRI and PET will be exploratory as no previous studies have been conducted.
RESEARCH PLAN For the sub-study, the investigators aim to recruit 25 PD patients with LID, 25 PD patients without LID, and 25 age-matched healthy controls.
4,487 studies on the registry are indexed under Parkinson Disease; 1,082 are open to participants now.
This study's planned enrollment of 75 is below the median of 96 across 1,057 observational studies indexed under Parkinson Disease.
Browse Parkinson Disease studies →Danish Research Centre for Magnetic Resonance is the lead sponsor of 14 studies on the registry; 9 are open to participants now.
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Healthy volunteers, age- and sex-matched the PD groups
Exclusion Criteria:
Inclusion criteria: * Aged 18 or more * Clinically established or probable PD according to the Movement Disorder Society Clinical Diagnostic Criteria for Parkinson's Disease * Peak-of-dose levodopa-induced dyskinesia * Stable antiparkinsonian medicine for 4 weeks * Signed informed consent Exclusion criteria: * Pregnancy or breastfeeding * History of other neurologic or psychiatric disease * Pacemaker or other implanted metallic or electronic devices which contraindicate MRI or TMS of the brain * Claustrophobia
Other: No intervention
Inclusion criteria: * Aged 18 or more * Clinically established or probable PD according to the Movement Disorder Society Clinical Diagnostic Criteria for Parkinson's Disease * No levodopa-induced dyskinesia * Stable antiparkinsonian medicine for 4 weeks * Signed informed consent Exclusion criteria: * Pregnancy or breastfeeding * History of other neurologic or psychiatric disease * Pacemaker or other implanted metallic or electronic devices which contraindicate MRI or TMS of the brain * Claustrophobia
Other: No intervention
Inclusion criteria: * Aged 18 or more * Age- and sex-matched the PD groups * Signed informed consent Exclusion criteria: * Pregnancy or breastfeeding * History of other neurologic or psychiatric disease * Pacemaker or other implanted metallic or electronic devices which contraindicate MRI or TMS of the brain * Claustrophobia
Other: No intervention
No intervention will be given.
Percent Mean Change in Blood Oxygen-level Dependent (BOLD) Scores During Modified Go/No-Go Task
For each participant and each run, we will create general linear models with 20 regressors of interest. The regressors are Motor: Right, Left, and No-Go trials Emotion: Happy, Neutral, Sad Reward: High/low reward, high/low loss All above regressors will be separately modeled for the high- and the low-reward context. We will add a linear time modulation to all regressors to model dynamic changes in activation over time.
Time frame: 4 task runs of 10 minutes each
Peak force
Measured with grip-force response. The data will be smoothed and normalized to the individual maximum voluntary contraction.
Time frame: 4 task runs of 10 minutes each
Reaction time
Measured with grip-force response.
Time frame: 4 task runs of 10 minutes each
Maximum slope
Maximum value of first derivative of grip-force curve. Measured with grip-force response. The data will be smoothed and normalized to the individual maximum voluntary contraction.
Time frame: 4 task runs of 10 minutes each
Maximal negative slope
Maximum negative value of first derivative of grip-force curve. Measured with grip-force response. The data will be smoothed and normalized to the individual maximum voluntary contraction.
Time frame: 4 task runs of 10 minutes each
Parkinson's disease severity
Total Unified Parkinson's Disease Rating Scale (UPDRS) score (sum of all 4 subscores listed below, range 0-199, higher values = worse outcome), UPDRS-1 (Cognitive and mental disease severity, range 0-16, higher values = worse outcome), UPDRS-2 (disease severity in relation to activities of daily living, range 0-52, higher values = worse outcome) and UPDRS-3 (Motor severity, range 0-108, higher values = worse outcome), UPDRS-4 (Complications of therapy, range 0-23, higher values = worse outcome) subscores. Measured while subjects are taking their usual medication.
Time frame: Baseline (normal medication)
Motor disease severity
Unified Parkinson's Disease Rating Scale (UPDRS)-3 subscore (Motor severity, range 0-108, higher values = worse outcome). Measured while subjects are taking their usual medication. Unified Parkinson's Disease Rating Scale (UPDRS)-3 subscore (Motor severity, range 0-108, higher values = worse outcome). Measured while subjects are taking their usual medication. Unified Parkinson's Disease Rating Scale (UPDRS)-3 subscore (Motor severity, range 0-108, higher values = worse outcome). Measured while subjects are taking their usual medication.
Time frame: Before and 30-60 minutes after 150 % of normal morning levodopa dose as Madopar Quick.
Non-motor disease severity
Total Non-Motor Symptom Scale (NMSS) score (range 0-360, higher values = worse outcome). Measured while subjects are taking their usual medication.
Time frame: Baseline
Non-motor fluctuation severity
Total Non-Motor Fluctuation Assessment (NoMoFA) score (range 0-84, higher values = more severe non-motor fluctuations). Measured while subjects are taking their usual medication.
Time frame: Baseline
Modified Hoehn and Yahr Staging
Modified Hoehn and Yahr Staging (Crude measure of disease severity, range 0-5, higher score = worse outcome). Measured while subjects are taking their usual medication.
Time frame: Baseline
Schwab and England Activities of Daily Living Scale
Schwab and England Activities of Daily Living Scale (Measure of ADL function, range 100-0%, higher score = better ADL function). Measured while subjects are taking their usual medication.
Time frame: Baseline
Apathy
Total Lille Apathy Rating Scale (LARS) score (range -36-36, higher score = higher degree of apathy).
Time frame: Baseline
Depression
Major Depression Inventory (MDI) score (range 0-50), higher score = higher degree of depression
Time frame: Baseline
Impulsive-Compulsive Disorders (ICD)
Questionnaire for Impulsive-Compulsive Disorders (QUIP) (range 0-112), higher score = higher degree of ICD
Time frame: Baseline
Cognitive function
The Montreal Cognitive Assessment (MoCA) (range 0-30), higher score = better cognitive performance
Time frame: Baseline
Impulsivity
Barratt Impulsiveness Scale (BIS-11) (range 30-120), higher score = higher level of impulsivity.
Time frame: Baseline
Dyskinesia severity
Unified Dyskinesia Rating Scale (UDysRS)
Time frame: Baseline (usual medication intake) as well as before and 30-60 minutes after 150 % of normal morning levodopa dose as Madopar Quick (range 0-104), higher score = higher dyskinesia severity
Dopaminergic degeneration
Dopamine transporter (presynaptic) binding in the basal ganglia is measured using Fluorine-18 N-(3-iodopro-2E-enyl)-2beta-carbomethoxy-3beta-(4'-methylphenyl) nortropane Positron Emission Tomography to
Time frame: Baseline
Age
Time frame: Baseline
Disease duration of Parkinson's disease
Time frame: Baseline
Duration of levodopa-induced dyskinesia
Time frame: Baseline
Medication
Time frame: Baseline
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Danish Research Centre for Magnetic Resonance