Brain GABA Levels and Treatment Response in Major Depressive Disorder
Brain GABA Levels and Treatment Response in Major Depressive Disorder
This study will evaluate changes in brain gamma-aminobutyric acid (GABA) levels due to
 treatment with escitalopram in people with major depressive disorder.
Major depressive disorder (MDD) is a severe form of depression. MDD can significantly
 interfere with an individual's thoughts, behavior, mood, and physical health. People who
 suffer from MDD often experience feelings of worthlessness; they may feel hopeless and may be
 unable to cope with problems in their life. In addition, they often experience sleep
 disruption, loss of appetite, and chronic pain.

 The purpose of the study is to compare images taken of the brains of people who are depressed
 and the brains of healthy volunteers. Specifically, we want to see if symptoms of depression
 are related to a decrease in a brain chemical called GABA. We measure the concentration of
 GABA using a brain-scanning device called "magnetic resonance spectroscopy" (or "MRS"), which
 is a type of MRI.

 The study lasts for 14 weeks and involves 8 visits to our MGH clinic in Boston. The first
 visit is the screening visit, which can last up to 3 hours. The rest of the visits are about
 a half hour long and take place every other week. In addition to these 8 visits, there are
 also 2 visits to McLean Hospital Brain Imaging Center for the MRS scans. The first scan takes
 place within a few days after the screening visit, and the second scan will be at the end of
 the 14 weeks. Each scan visit lasts between an hour and a half and two hours. Subjects are
 reimbursed $50 per MRS scan and $25 per visit to McLean to cover travel costs.

 All subjects in this study will receive escitalopram (or Lexapro), which is an antidepressant
 medication approved by the Food and Drug Administration. Subjects start at 10 mg daily of the
 escitalopram, but may be increased up to 30 mg if the study doctor thinks it is appropriate.
Inclusion Criteria:

 -  Meet diagnostic criteria for current Major Depressive Disorder

 -  Men or women aged 18-65

 -  Medication-free for one week prior to the start of the study

 -  Agrees to use an effective form of contraception throughout the study

 Exclusion Criteria:

 -  Anyone who is suicidal

 -  Pregnant or breastfeeding women

 -  Anyone with a serious or unstable medical illness, including cardiovascular, hepatic,
 renal, respiratory, endocrine, neurologic or hematologic disease

 -  Anyone with a history of seizure disorder or hypothyroidism

 -  Anyone with a history of psychiatric disorders including bipolar disorder,
 schizophrenia, psychoses, or substance abuse (including alcohol abuse active within
 the last 12 months)

 -  Anyone with a history of intolerance or multiple adverse drug reactions or allergy to
 (es)citalopram.

 -  Patients who are currently taking medications active on GABA, including
 benzodiazepines.