Altered Brain GABA and Glutamate in Restless Legs Syndrome (RLS)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01109537
Recruitment Status : Completed
First Posted : April 23, 2010
Last Update Posted : January 7, 2015
Information provided by (Responsible Party):
John W. Winkelman, MD, PhD, Brigham and Women's Hospital

Brief Summary:
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.

Condition or disease
Restless Legs Syndrome

  Show Detailed Description

Study Type : Observational
Actual Enrollment : 75 participants
Observational Model: Case Control
Time Perspective: Prospective
Official Title: Thalamic and Anterior Cingulate Cortex GABA and Glutamate in Restless Legs Syndrome: A 1-HMRS Study
Study Start Date : April 2010
Actual Primary Completion Date : May 2014
Actual Study Completion Date : May 2014

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Restless Legs

RLS Diagnosis
Healthy Controls

Primary Outcome Measures :
  1. Regional GABA and glutamate levels derived from 4T MRS. [ Time Frame: 2 years ]

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
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.

Inclusion Criteria:

  • 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

Exclusion Criteria:

  • 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:
  • Cardiac pacemakers
  • Aneurysm clips and other vascular stents, filters, clips or other devices
  • Prosthetic heart values
  • Other prostheses
  • Neuro-stimulator devices
  • 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)
  • Other metallic surgical hardware in vital areas
  • Severe claustrophobia

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01109537

United States, Massachusetts
Sleep HealthCenters
Brighton, Massachusetts, United States, 02135
Sponsors and Collaborators
Brigham and Women's Hospital
Principal Investigator: John W Winkelman, MD, PhD Sleep Health Centers, Brigham and Women's Hospital


Responsible Party: John W. Winkelman, MD, PhD, Associate Professor of Psychiatry, Harvard Medical School, Brigham and Women's Hospital Identifier: NCT01109537     History of Changes
Other Study ID Numbers: BWH-2010-12345
First Posted: April 23, 2010    Key Record Dates
Last Update Posted: January 7, 2015
Last Verified: January 2015

Keywords provided by John W. Winkelman, MD, PhD, Brigham and Women's Hospital:
Restless Legs Syndrome (RLS)
Magnetic Resonance Spectroscopy

Additional relevant MeSH terms:
Psychomotor Agitation
Restless Legs Syndrome
Pathologic Processes
Neurologic Manifestations
Nervous System Diseases
Psychomotor Disorders
Neurobehavioral Manifestations
Signs and Symptoms
Sleep Disorders, Intrinsic
Sleep Wake Disorders
Mental Disorders