Sex/Gender Differences in Risk and Resilience to PTSD; Implication of Oxytocin
Condition: PTSD
Intervention: Oxytocin; Placebo
Intervention MeSH terms: Oxytocin
Phase: Phase 2
Study type: Interventional
Primary purpose: Other
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Investigator)
Enrollment: 38.0
Sex: All
Minimum age: 18 Years
Maximum age: 50 Years
Healthy volunteers: No

Summary:

      The purpose of the study is to use fMRI to investigate amygdala response to fearful faces in
      men and women with and without PTSD who have experienced childhood trauma. The study will
      also compare the effects of oxytocin and placebo on amygdala response, and explore the
      interaction of oxytocin plasma levels and amygdala response in men and women with and without
      PTSD who have experienced childhood trauma.

      Hypothesis 1: Amygdala responding will be greater in subjects with PTSD as compared to
      resilient subjects, and no sex differences in the magnitude of the response will be found.

      Hypothesis 2A: In response to OT, women will exhibit a greater reduction in amygdala
      responding than men.

      Hypothesis 2B: In response to OT, women with PTSD will exhibit a greater reduction in
      amygdala responding compared to women without PTSD.

      Hypothesis 3A: Women with PTSD will have lower levels of plasma OT as compared to men with
      PTSD, and women and men without PTSD.

      Hypothesis 3B: Plasma OT levels will be inversely correlated with amygdala responding to
      fearful faces in women but not in men.
    

Eligibility criteria:

        Inclusion Criteria

          1. Ages 18-60.

          2. Subjects scoring moderate to severe (>3) on a minimum of one of the five trauma
             domains of the Childhood Trauma Questionnaire.

          3. Subjects must have experienced, witnessed, or confronted an event(s) that involved
             actual or threatened death or serious injury, or a threat to the physical integrity of
             themselves, or others and the person's response involved intense fear, helplessness,
             and/or horror (Criterion A DSM-IV for PTSD), prior to the age of 18.

        Exclusion Criteria

          1. Subjects with evidence of or a history of head trauma, neurological disorders,
             seizures, unconsciousness or any other major medical disorder.

          2. Subjects with current (past 90 days) psychotic disorder or bipolar affective disorder.

          3. Subjects with any psychoactive substance abuse within the last 30 days as evidenced by
             subject report or urine drug screen.

          4. Women who are pregnant or nursing.

          5. Women who are post-menopausal or have had a full hysterectomy.

          6. Subjects who have a BMI greater than 35.

          7. Subjects who are unwilling to maintain abstinence from alcohol and caffeine for the
             24-hour period prior to the study visits and from illicit drug use for the 72 hour
             period prior to study visits.

          8. Persons with ferrous metal implants or pacemaker.

          9. Subjects who are claustrophobic.

         10. Subjects taking endocrine or cardiovascular medications (other than blood pressure
             medications) during the 30-day period prior to the study.

         11. Subjects with a postive breathalyzer or urine drug screen. Group - Specific
             Inclusion/Exclusion Criteria Individuals with PTSD Inclusion Criteria

        1. Subjects must meet DSM-IV criteria for current (i.e. last 6 months) PTSD. 2. Subjects
        may also meet criteria for a mood disorder (except bipolar affective disorder, see
        Exclusion Criteria) or other anxiety disorders (panic disorder, agoraphobia, social phobia,
        generalized anxiety disorder, or obsessive compulsive disorder) or past (>90 days) alcohol
        dependence. The inclusion of subjects with affective and other anxiety disorders is
        essential because of the marked frequency of the co-existence of mood and other anxiety
        disorders among patients with PTSD (Brady, Killeen, Brewerton, & Lucerini, 2000; Kessler,
        Chiu, Demler, Merikangas, & Walters, 2005).

        Exclusion Criteria

          1. As above.

          2. Substance dependence within the past year, except for nicotine or alcohol. Resilient
             Controls Inclusion Criteria

        1. As above. Exclusion Criteria

        1. Subjects meeting criteria for current or past (i.e. last 90 days) Axis I mood or anxiety
        disorders (including PTSD and depression).