Non-invasive exploration of the pathophysiology and neurochemistry of restless legs syndrome Nervous System Diseases
Conditions
Interventions
Each participant will receive dipyridamole, caffeine, or a placebo in a random sequence determined by computer-generated random numbers. The administration will occur during three different TMS sessio
dosage given: 75 mg
method and frequency of administration: single oral administration
total duration of treatment: 1 day
follow-up: none.
Caffeine arm: caffeine
dosage given: 200 mg
follow-up: none.
Sponsors
Oasi Research Institute-IRCCS
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. Age 18-65 years 2. Diagnosis of RLS according to the latest criteria by the International RLS Study Group 3. RLS symptoms on 3 or more days per week for at least 3 months 4. International RLS Rating Scale (IRLS-RS) score >15 (i.e., moderate symptomatology, at least) 5. Normal brain magnetic resonance imaging (MRI) and upper limb electromyography (EMG), including the study of the F-waves 6. Women of childbearing potential must have a negative pregnancy test and agree not to become pregnant during the whole experimental procedure 7. Personally signed and dated informed consent obtained before any procedure. All personal information about potential and enrolled participants will be collected and maintained, in order to protect confidentiality before, during, and after the whole procedure
Exclusion criteria
Exclusion criteria: 1. Drug intake affecting cortical excitability or cognitive performance, including those used for RLS 2. Mini Mental State Examination score <24 3. Any major psychiatric disease 4. Other neurological or sleep disorders 5. Severe, untreated, acute, or not compensated medical illness 6. Any secondary form of RLS (i.e. renal failure, anemia, low serum iron and ferritin levels, pregnancy, peripheral neuropathy, etc.) 7. Contraindication to dipyridamole and/or caffeine intake 8. Any condition precluding MRI or TMS execution, such as the presence of a cardiac pacemaker, defibrillator, or mechanical valve, presence of non-compatible joint prostheses, previous neurosurgical procedures, and, for TMS only, seizure or history of epilepsy. A conventional EEG will be also performed in order to exclude a predisposition to seizure.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| 1. Resting motor threshold (%) 2. Cortical silent period (ms) 3. Latency and amplitude of the motor evoked potentials (ms/mV) 4. Central motor conduction time (ms) 5. Intracortical inhibition (ratio) 6. Intracortical facilitation (ratio) All these measures, elicited through specific transcranial magnetic stimulation (TMS) protocols, will be performed at baseline and 1 hour after the administration of dipyridamole, caffeine, or placebo. | — |
Secondary
| Measure | Time frame |
|---|---|
| Correlation between TMS metrics (please see those listed among primary outcome measures) and psycho-cognitive assessment, in order to screen RLS patients for cognitive impairment and/or mood-behavioral dysfunction: 1. Vocabulary assessed using the Wechsler Adult Intelligence Scale 2. Presence of sleep disorders assessed using the Global Sleep Assessment Questionnaire 3. Sleep quality assessed using the Pittsburgh Sleep Quality Index 4. Severity of depression assessed using the Beck Depression Inventory II 5. State and trait anxiety assessed using the State-Trait Anxiety Inventory Correlations will be performed at baseline only, since psychocognitive tests are not repeated after 1 hour. | — |
Countries
Italy
Contacts
Public ContactRosa Di Giorgio
Outcome results
None listed