Altered Brain GABA and Glutamate in Restless Legs Syndrome (RLS)
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ClinicalTrials.gov Identifier: NCT01109537
: April 23, 2010
Last Update Posted
: January 7, 2015
Brigham and Women's Hospital
Information provided by (Responsible Party):
John W. Winkelman, MD, PhD, Brigham and Women's Hospital
The purpose of the study is to understand the brain chemistry of people with Restless Legs Syndrome (RLS). The primary hypothesis is that patients with RLS will have reduced GABA levels in their Thalamus and elevated Glutamate levels in their Anterior Cingulate Cortex. The study will use MRS imaging to examine the regional levels of these neurochemicals, GABA and Glutamate, in the brain.
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Ages Eligible for Study:
18 Years and older (Adult, Senior)
Sexes Eligible for Study:
Accepts Healthy Volunteers:
Male and female subjects who have RLS or are normal controls will be recruited from the greater Boston metropolitan area. We anticipate enrolling 70 subjects with RLS and 70 normal controls, under a plan to complete 15 subjects in each group.
Subjects at least 18 years of age
Subjects with a diagnosis of RLS using the International RLS Study Group (IRLSSG) criteria
Subjects with a history of RLS symptoms at least 15 nights in the prior month, or, if on treatment, this frequency of symptoms before treatment was started
Subjects who are unable to discontinue prohibited medications prior to sleep study and 1H-MRS. These include any CNS-active medications. For RLS subjects, RLS-related medications (e.g. dopaminergic agents and alpha 2-delta agents) must be discontinued a minimum of 48 hours prior to PSG. In the RLS group, benzodiazepines must be discontinued a minimum of one week prior to PSG. For normal controls with regular treatment (>1 time/wk) with CNS active agents within 1 month of screening visit will also be excluded.
Subjects with an active or unstable major psychiatric disorder requiring further treatment (e.g., major depressive disorder). Subjects with clinically significant depression, or with clinically significant anxiety, or who, in the investigator's judgment might require intervention with either pharmacological or non-pharmacological therapy over the course of the study.
Subjects with clinical evidence of any untreated moderate to severe sleep disorder other than RLS (forRLS group) (e.g. obstructive sleep apnea, insomnia, narcolepsy, delayed sleep phase syndrome, etc.) within the preceding year
Subjects with an apnea-hypopnea index (AHI) > 15 at the polysomnography visit
Subjects who consume beverages containing more than 400mg of caffeine per day
Subjects who consume more than 14 alcoholic units in any week, or more than 5 alcoholic units in any single day, over the month preceding the screening visit.
Females who are pregnant or lactating
Subjects with a history of neurologic illness (e.g. brain neoplasm, multiple sclerosis), significant or unstable medical illness (e.g. congestive heart failure, diabetes mellitus), or history of significant head trauma or loss of consciousness > 30 minutes
Subjects who have positive urine drug screening (phencyclidine, cocaine, amphetamines, tetrahydrocannabinol, and opiates) at the screening visit or at the MRS visit.
Contraindications to MRS scans, including:
Aneurysm clips and other vascular stents, filters, clips or other devices
Prosthetic heart values
Implanted infusion pumps
Cochlear (ear) implants
Ocular (eye) implants or known metal fragments in eyes
Exposure to shrapnel or metal filings (sheetmetal workers, welders, and others)