Cortisol Suppression and Startle Responses in Posttraumatic Stress Disorder (PTSD)

NCT01477762 | Completed Results DMC

• 2 other identifiers: IRB000519111R21MH092576-01A1
• Study Type: interventional
• Target: 165
• Locations: 1 country
• Sites: 1

Brief Summary

Posttraumatic stress disorder (PTSD) occurs in some people after exposure to events that cause extreme fear or helplessness. The incidence of war zones worldwide and the prevalence of violence in large cities in the U.S., increases the likelihood that people will experience a traumatizing event in their lifetime. About 1 in 10 people who survive such events will develop PTSD, while most people will get better over time. This suggests that some people may have biological vulnerabilities that make it harder for them to recover. One of these biological risk factors may be related to how stress hormones work in people who get sick. Another is how people react to things that make them afraid or nervous, investigators have found that PTSD patients have higher than normal fear reactions. The part of the brain that reacts to fearful stimulation is linked to stress hormones; the purpose of this study is to examine how these systems interact. The study will suppress stress hormones (cortisol) production in one group of participants, while another will get a placebo. When their cortisol is suppressed, the participants will undergo a startle study to see if their fear responses are decreased. Investigators expect that people PTSD will show a normal fear response when their cortisol levels are reduced, similar to people without PTSD. This research can help discover new medicines for people with PTSD.

Conditions

Post Traumatic Stress Disorder

Keywords

startle response; fear conditioning; PTSD

Outcome Measures

Primary Outcomes (4)

• Mean Baseline Startle Magnitude During Fear Conditioning

  The study measured the acoustic startle response magnitude to a sudden noise using electromyography of the eyeblink muscle. This response magnitude was used as the individual's baseline to compare to the startle magnitude to the danger signal to see if fear conditioning had occurred.

  10 hours after drug administration

• Mean Startle Magnitude to Danger Signal During Fear Conditioning

  The acoustic startle response magnitude was measured using electromyography recordings of the eyeblink muscle when a sudden tone was delivered through headphones in the presence of a stimulus that was paired with an aversive outcome (i.e. the danger signal). If an individual showed successful fear learning, then startle to the danger signal would be greater than baseline startle.

  10 hours after drug administration

• Mean Fear-potentiated Startle to Danger Signal During Early Extinction

  Fear-potentiated startle was measured as a difference score between the startle to danger signal and the baseline. This difference score reflects the degree of fear response at the beginning of extinction.

  10 hours after drug administration

• Mean Fear-potentiated Startle to Danger Signal During Late Extinction

  This measures the level of fear-potentiated startle (the difference between startle magnitude to the danger signal and baseline startle magnitude) at the end of extinction. Because the danger signal is no longer paired with the aversive stimulus like it was during the conditioning phase, the fear response should decrease from early to late extinction in individuals who show intact extinction learning.

  10 hours after drug administration

Study Arms (2)

PTSD Negative

ACTIVE COMPARATOR

Participants who do not have PTSD will receive placebo and dexamethasone in random order for the duration of two consecutive study visits separated by at least one month.

Drug: Dexamethasone; Drug: Placebo

PTSD Positive

EXPERIMENTAL

Participants with PTSD will receive placebo and dexamethasone in random order for the duration of two consecutive study visits separated by at least one month.

Drug: Dexamethasone; Drug: Placebo

Interventions

Dexamethasone DRUG

One tablet of 0.5 mg dexamethasone will be taken ten hours prior to completing study assessments.

PTSD Negative; PTSD Positive

Placebo DRUG

One placebo tablet will be taken ten hours prior to completing study assessments.

PTSD Negative; PTSD Positive

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Able to give informed consent
• Willing to participate in initial assessment and 2 full days of interviews and imaging visit
• Able to understand English and no obvious deficit in comprehension or following directions
• years old

You may not qualify if:

• Mental Retardation (per clinical judgment of study physician)
• Psychotic Disorder (per clinical judgment of study physician)
• Acute suicidal ideation
• Pregnancy
• Positive urine drug screen
• Active medical disorders contributing to psychiatric sx e.g. hypo or hyperthyroidism, SLE, advanced cirrhosis, etc. (per clinical judgment of study physician)

Sponsors & Collaborators

• Emory University: lead
• National Institute of Mental Health (NIMH): collaborator

Study Sites (1)

Grady Health System

Atlanta, Georgia, 30303, United States

Location

Related Publications (1)

• Jovanovic T, Phifer JE, Sicking K, Weiss T, Norrholm SD, Bradley B, Ressler KJ. Cortisol suppression by dexamethasone reduces exaggerated fear responses in posttraumatic stress disorder. Psychoneuroendocrinology. 2011 Nov;36(10):1540-52. doi: 10.1016/j.psyneuen.2011.04.008. Epub 2011 May 20.

  PMID: 21601366 BACKGROUND

Related Links

• Related Info

MeSH Terms

Conditions

Stress Disorders, Post-Traumatic

Interventions

Dexamethasone

Condition Hierarchy (Ancestors)

Stress Disorders, Traumatic; Trauma and Stressor Related Disorders; Mental Disorders

Intervention Hierarchy (Ancestors)

Pregnadienetriols; Pregnadienes; Pregnanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Steroids, Fluorinated

Results Point of Contact

• Title: Dr. Tanja Jovanovic
• Organization: Emory University

tjovano@emory.edu

(404) 778-1485

Study Officials

• Tanja Jovanovic, PhD

  Emory University

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: November 17, 2011
• First Posted: November 23, 2011
• Study Start: November 1, 2011
• Primary Completion: July 1, 2015
• Study Completion: July 1, 2015
• Last Updated: April 18, 2017
• Results First Posted: April 18, 2017

Record last verified: 2017-03

Locations

US (1)