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

This study has been completed.
Information provided by (Responsible Party):
John W. Winkelman, MD, PhD, Brigham and Women's Hospital Identifier:
First received: April 22, 2010
Last updated: January 6, 2015
Last verified: January 2015
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.

Restless Legs Syndrome

Study Type: Observational
Study Design: 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

Resource links provided by NLM:

Further study details as provided by Brigham and Women's Hospital:

Primary Outcome Measures:
  • Regional GABA and glutamate levels derived from 4T MRS. [ Time Frame: 2 years ] [ Designated as safety issue: No ]

Enrollment: 75
Study Start Date: April 2010
Study Completion Date: May 2014
Primary Completion Date: May 2014 (Final data collection date for primary outcome measure)
RLS Diagnosis
Healthy Controls

  Show Detailed Description


Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
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
  Contacts and Locations
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, see Learn About Clinical Studies.

Please refer to this study by its identifier: 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
  More Information


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
Study First Received: April 22, 2010
Last Updated: January 6, 2015
Health Authority: United States: Institutional Review Board

Keywords provided by Brigham and Women's Hospital:
Restless Legs Syndrome (RLS)
Magnetic Resonance Spectroscopy

Additional relevant MeSH terms:
Psychomotor Agitation
Restless Legs Syndrome
Mental Disorders
Nervous System Diseases
Neurobehavioral Manifestations
Neurologic Manifestations
Pathologic Processes
Psychomotor Disorders
Signs and Symptoms
Sleep Disorders
Sleep Disorders, Intrinsic processed this record on November 24, 2015